Post by: gsxrpig on January 10, 2017, 02:02:05 AM
Bit of history.
1990 K100lt in Australia. Bought as a non runner but PO, said sprag clutch and fuel pump were Known faulty.
Cafe racer conversion, so have eliminated clutch switch and gear positioning but kept the neutral light with the help of the forum members. Cahnges the instrument panel.
i have put in a new fuel pump as the last one had sat for many years and the mount had perished, holes in the tank and the usual problems. So throttle bodies have been cleaned new pump and new regulator and new lines. Also reconditioned injectors and new plugs. Checked firing order.
SO was excited to put everything back together and ready to start the bike.
Fuel pump is pumping and bike is cranking well.
BUT the injectors are not letting fuel in. Absolutley nothing through the new injectors.
I have downloaded Bert' troubleshooting guide...which is phenomenal but I cannot seem to get it to run.
Had a electrician friend come over today and we ran all the tests.
We have 12V at the red and green but can seem to get the negative pulse.
Checked all the grounds I can find cleaned and checked for continuity.
I am getting spark on all 4 plugs.
12v at red green injector when cranking. BUT also 12V on yellow when cranking...only have a digital volt meter so it may not be correct to read the pulse here.
Ground to injectors at efi as test is close to expected resistance values.
i am trying to source an alternative EFI unit to test in the bike.
Any ideas would be great. spent days looking into posts on here and testing various things on the bike. Have swapped out relays.
I am out of ideas, maybe in all my modification i have missed something electrical in the safety features? It seems to be getting 12v to injectors but not sending the ground pulse to allow them to open??
Any help would be great. It is beer time here in Australia so I will be out of contact till tomorrow but i will continue to read Berts guide and hope someone has a light bulb moment.
Post by: Laitch on January 10, 2017, 07:12:41 AM
Had a electrician friend come over today and we ran all the tests.At which box on Bert's chart have you stopped? You can or you can't get the negative pulse. The but in that sentence is tending to skew its meaning for me.
We have 12V at the red and green but can seem to get the negative pulse.
Post by: K1300S on January 10, 2017, 12:18:35 PM
"fuel pump is pumping" ...is that known because you can hear it or because you have actually seen fuel pressure at the fuel rail?
just confirming basics....
Post by: gsxrpig on January 10, 2017, 05:45:34 PM
No ticking from injectors at all...new reco injectors.
Have taken rail off and no evidence of fuel getting through injectors when cranking.
Brand new plugs....dry as a chip.
I have 12Volt at Green and red when pressing the start button.
Also 12V on yellow and grey when pressing the start button.
I am unsure of how to test that pulse with the tools I have. Hooking up an Led test light I do not get a pulse effect ??
Hooking my test light to positive on battery and connect to female pin 12 on ECU will provide green light before pressing the starter button...this stops until I release the start button. to confirm that multi meter is measuring nothing at pin 12 then 11.75 volts when button is pressed.
Post by: gsxrpig on January 10, 2017, 07:03:07 PM
So I presume that it must be at suffice pressure to get past the new regulator.
I am still trying to find a gauge to confirm that 36psi pressure figure.
Thanks for the replies so far...really want to solve this issue and get this project completed.
I think I may have found a local guy with a running bike that is willing to swap his ecu into mine or vice versa and test that component.
It may come back to my initial wiring...removal of the instrument cluster gear indicator and clutch and choke switches. I thought i had the all clear on that section. under a different post. "USD fork swap"
The only other thing I will test now is I removed the warning light for the Temperature. As i am running a gauge now. Hope with the forum I can find the problem.
Post by: gsxrpig on January 11, 2017, 12:28:35 AM
Only getting readings on ohms in the 20k setting.
at approx 30 deg the resistance is 3.79
If i the place it in boiling water the resistance goes steadily down to 1.03.
So resistance is changing with rise in temperature.
I only have a cheap meter and it won't seem to read in lower settings.
I have searched through and found some settings and the boiling temperature seems to still be a high resistance.
Even though the resistance is changing this still high reading may indicate a faulty sensor?
Anyone got any ideas..
Post by: The Mighty Gryphon on January 11, 2017, 01:47:02 AM
Post by: Laitch on January 11, 2017, 06:01:34 AM
That would result in an overly rich mixture because it's telling the ecu the engine is cold which isn't your problem as I understand it.His problems seems to be his injectors aren't providing any fuel.
Please put the model of your bike in your profile. Is it an LT, or an RS?
Post by: Laitch on January 11, 2017, 10:17:33 AM
Post by: The Mighty Gryphon on January 11, 2017, 11:50:55 AM
His problems seems to be his injectors aren't providing any fuel.
That was my point.
Post by: Laitch on January 11, 2017, 12:30:02 PM
That was my point.That was my reality check. :giggles Now I've just been told it isn't April. :yow
Post by: kennybobby on January 11, 2017, 12:40:05 PM
There is a big transistor in the ecu that provides the path to ground for the injectors. If it is not switching then you get no fuel. Swapping will let you know if your transistor circuit is defective e.g. bad solder joint, or if you are not receiving some sensor or timing signal into the jetronic. So make the swap and report the result.
Post by: gsxrpig on January 11, 2017, 05:50:51 PM
As far as resistance decreasing as the temperature increases, your sensor appears to be functioning properly. As far as being in or out of the proper range, it appears to be reading a bit high if I recall. That would result in an overly rich mixture because it's telling the ecu the engine is cold which isn't your problem as I understand it.
Yes I agree. I thought that if it was faulty it might send a signal to the ECU and prevent the bike from starting...by stopping the injectors from firing. I am just hitting every angle I can at the moment. It must be something simple but I can't seem to track it down at this stage. I am a Jap bike man and the Bmw is very foreign to me.
LAITCH, sorry for the confusion...I did put the details in the opening post along with a bit of history to supply the forum with hopefully some bits of info which might help.
KENNYBOBBY it is a L-jetronic control unit and From my research people are saying they are very reliable, Maybe I am clutching at straws I don't know but worth a shot.
Plan on putting my unit in his functioning bike first and see if it works, the swap his into mine.
I seem to be getting 12V to the injectors but like I said earlier I am unsure I am getting the pulse signal and am a bit unsure how to positively check with the tools I have. I have got some noid test lights coming with a mate next week but want to try and get this bike going before then because I am an impatient bastard.
Thanks for the replies everyone and please keep them coming. I will continue to put up my test results in the hope it will trigger an obvious or not so obvious answer from someone. :dunno2:
Post by: Laitch on January 11, 2017, 06:01:42 PM
Plan on putting my unit in his functioning bike first and see if it works, the swap his into mine.Fergawdsake, get it over with! You're interfering with valuable Netflix time. :giggles
Thanks for updating your profile. That way people don't need to backtrack to find out what's being worked on. People are eager to help but not so eager to Easter egg hunt. You still haven't answered my question about which box you were stalled at in Vogel's chart.
Post by: gsxrpig on January 11, 2017, 06:55:29 PM
Fergawdsake, get it over with! You're interfering with valuable Netflix time. :gigglesMate I am at the mercy of the bloke donating the use of his ECU...He isn't due till the weekend. Don't worry if I had it. it would already have been tested.
Thanks for updating your profile. That way people don't need to backtrack to find out what's being worked on. People are eager to help but not so eager to Easter egg hunt. You still haven't answered my question about which box you were stalled at in Vogel's chart.
2 more days wait.
As for the boxes...I am basically stalled at the pulsing negative at pin 12....As a couple of posts up I showed the results but as for pulsing I cannot be positive... Positive no fuel is getting past with reconditioned injectors so to me i ain't getting that pulse.?
My only other thoughts is the safety features that I have eliminated are coming back to haunt me and telling the ECU not to fire the injectors. But I would have thought it wouldn't crank at all.
Hence the posts and trying to feed as much info back to the forum so I am not misleading anyone.
Post by: Laitch on January 11, 2017, 07:27:26 PM
I am at the mercy of the bloke donating the use of his ECU...He isn't due till the weekend.Thanks for the update.
If it were my bike, I'd turn my attention to something else and quit ruminating on this. There must be something else. The one upbeat factor about all this is that the previous owner was honest about the bike's condition.
You're thinking it must be something simple. I think you're right. Replacing a Jetronic is simple. You'd be far from the first to have it be the remedy, as kennybobby has already suggested. If you want to be obsessive, you can review all your connections, double check your results of having followed the instructions you were given here for the disabling of switches, and review the wiring diagram here for early K100RT/RS models until your friend arrives.
You could also just enjoy a walk in tropical weather and deal with it all on the weekend. My driveway is a sheet of sand-laced ice.
Post by: gsxrpig on January 11, 2017, 08:04:02 PM
here....stuck at work ....and 2 bikes down and nothing to ride :yes
Post by: Laitch on January 11, 2017, 08:13:15 PM
Well if it's any bonus to you its hot asi can feel the warmth in your response. I've closed the damper on the woodstove. :giggles Someday you'll look back on all this and laugh, maybe.
here....stuck at work ....and 2 bikes down and nothing to ride :yes
Post by: kennybobby on January 12, 2017, 06:42:18 AM
i would agree they are mostly reliable electronics, but i have repaired hundreds of Bosch units over the years and found the biggest culprit is broken solder joints on the large transistor leads. After years of vibration on the road the solder fatigues and cracks. It is an easy fix.
Post by: gsxrpig on January 12, 2017, 06:14:06 PM
While you're waiting you can figure out the rubber clips and pin holding the L-jet in place, and pull it out for inspection. Look at the bottom where the cover tabs are folded over and pressed into the slots--is there any evidence of tampering or marks from screwdrivers from previous owner's opening up the device?Thanks for the feedback kennybobby.
i would agree they are mostly reliable electronics, but i have repaired hundreds of Bosch units over the years and found the biggest culprit is broken solder joints on the large transistor leads. After years of vibration on the road the solder fatigues and cracks. It is an easy fix.
It is a cafe racer so the ecu has been moved to the rear, but it looks in very good shape and has not been opened by the looks....until now :eek:
A few projects ago on an xv750 cafe I was doing I chased my tail for months until finally biting the bullet and replacing the TCI...which I was told very rarely if ever fail....switched it over and the difference was amazing. Like you said,I think the age and heat of where it was located under the tank lead to its demise also.
I will resist opening this ECU until I get my hands on the test one tomorrow. Although I spose it can't hurt to have a look....
Not much left to do on the bike except get it running then I can do a final wiring cleanup and test and tune then roadworthy it. Might have to do some real work today :dunno
Post by: gsxrpig on January 13, 2017, 07:39:43 PM
No difference at all.
Put my unit in the donor bike and it never missed a beat.
Swapped his unit into mine and exact same issue.
Cranking but no firing.
I will pull the AFM and check the resistance readings again.
I have some Noid test lights on the way so that will confirm I am not getting the pulse.
Scratching my head big time here now.
Anyone with any ideas ...i will try any suggestions as I have none left.
Post by: Martin on January 13, 2017, 07:50:28 PM
Try pulling the injector and hook it up to a 9V battery to see if it works.
Regards Martin.
Post by: gsxrpig on January 13, 2017, 08:13:52 PM
reconditioned Injectors....tested and pulse out of bike.
:dunno
Post by: Scott_ on January 13, 2017, 08:22:54 PM
Sounds to me that your bike is not getting the input to tell the ECU to fire the injectors then, which is confusing to me as I thought the input to fire the injectors and also energizes the fuel relay.
Post by: gsxrpig on January 13, 2017, 08:52:06 PM
Well, the ECU works in another bike, so that says the injector output is good.Confusing indeed.
Sounds to me that your bike is not getting the input to tell the ECU to fire the injectors then, which is confusing to me as I thought the input to fire the injectors and also energizes the fuel relay.
Fuel relay is working, fuel pump primes and pressure at rail.
Post by: gsxrpig on January 13, 2017, 09:07:06 PM
The temp sensor has been tested and results earlier....even though it is a bit out of spec(new one ordered) like Griffin said the computer would think it was cold and should be running a bit rich. I have cut the wire to the warning light.
The TPS should be out of the equation on start up.
The AFM is what I will retest.
Does anyone have a way of bypassing the AFM to see if the bike will start?
Post by: gsxrpig on January 13, 2017, 09:33:28 PM
AFM has thrown a issue up.
From Berts chart.
My AFM results.
Pin 7-5 59 changes with vane movement.
Reading very low there.
The rest are spot on.
pin 7-8 is 335 changes with vane
Pin 8-5 is 361 and constant.
Pin 8-9 is 202.
The rubber stop at the vane does seem worn and is not flat ...but I got no idea what it should look like.
Post by: The Mighty Gryphon on January 13, 2017, 10:15:49 PM
http://bowlsby.net/914/Classic/zTN_Man15.pdf
Personally, I am thinking the problem is either the signal from the ignition control unit or the air flow sensor. It could be that the signal isn't there or there is a continuity problem in the wiring.
In any event, I would be double checking all the inputs to the ECU.
Post by: gsxrpig on January 13, 2017, 10:29:56 PM
Here is some bedtime reading that might help you understand how the L-Jetronic works.Thanks for the reply
http://bowlsby.net/914/Classic/zTN_Man15.pdf (http://bowlsby.net/914/Classic/zTN_Man15.pdf)
Personally, I am thinking the problem is either the signal from the ignition control unit or the air flow sensor. It could be that the signal isn't there or there is a continuity problem in the wiring.
In any event, I would be double checking all the inputs to the ECU.
So the test result on the AFM that I posted would that one difference be a cause do you think?
Continuity on wires is right. But I will have to recheck all the Ignition readings again. The electrician took the hall sensors out and tested them and they were working. But I will rerun everything and let you know.
I have been reading about the L jetronic and have just downloaded some reading on the AFM.
Post by: Laitch on January 13, 2017, 11:26:49 PM
In any event, I would be double checking all the inputs to the ECU.With the starter running, compare the Pin #8 value of your Ignition Control Unit/Electronic Ignition Module with Vogel's chart value: 10 to 20Mv. The fuel injection control unit needs an rpm signal for starting.
Post by: The Mighty Gryphon on January 13, 2017, 11:32:34 PM
With the starter running, compare the Pin #8 value of your Ignition Control Unit/Electronic Ignition Module with Vogel's chart value: 10 to 20Mv. The fuel injection control unit needs an rpm signal for starting.
That is one of the signals I was thinking of. I would go right to pin #1 on the ECU and make sure you have it. If not, work back from there.
Post by: gsxrpig on January 14, 2017, 01:05:56 AM
It is a stinker here today...Saturday and the bike is at work.
Pretty sure the electrician checked it and pretty sure my shit multi meter won't measure that low in volts.
But i will report back.
If I am missing that signal am I presuming faulty ignition control?
Post by: The Mighty Gryphon on January 14, 2017, 01:50:02 AM
You need to check the continuity of the wire from the ignition module to pin #1 of the ECU. My Clymer manual says it is a red wire with a yellow stripe. Clean the terminals at both ends. If Laitch is right about the 20mv signal, it won't take much to lose it.
If the wire is ok, it may be possible that the ignition module has a problem putting out the signal to the ECU. You will need to swap with a good module to confirm.
Post by: gsxrpig on January 15, 2017, 07:07:52 PM
Borrowed a better multi meter.
I have continuity between pin 8 ignition and pin 1 ECU
reading 32mV AC at pin 1 on the ECU when cranking.
Much higher than 10-20 mV on Berts list.
Any ideas?
Going to run the lot of tests again and double check my old results with the better meter.
Post by: gsxrpig on January 15, 2017, 09:35:02 PM
On ignition module
pin 7 ground to FI relay with starter is giving 1.42 Volts (0 to 1 V on chart)
Pin 8 Signal is fluctuating from as high as 47 to 32 mV ac (10-20mV on chart)
*****Pin 10 with starter running I can not get a reading *****(1.5 to 4V on chart)
Pin 9 and 14 both supply 1.5 to 2 Volts with starter.
On ECU
Pin 1 from Ignition is the same 47 to 32mV
Pin 10 is only reading about 1220 resistance. I took the sensor out and it was testing a bit high on the range. Have ordered a new one.
Pin 12 injector test
1 injector is 15 ohms
2 injectors is 8 ohms
3 injectors is 5.2 ohms
4 injectors is 4 ohms, so all pretty close.
My noid test lights turned up and as expected no pulsing at injectors, confirmed.
Post by: gsxrpig on January 15, 2017, 10:19:18 PM
Post by: The Mighty Gryphon on January 15, 2017, 11:59:17 PM
With your meter black wire on ground and the red on terminal 10 what do you read with the ignition switch off? Ignition switch on? Starter cranking?
Have you checked fuse #1 and cleaned it's terminals?
Post by: gsxrpig on January 16, 2017, 12:26:45 AM
Pin 10 on the ICU... You say you weren't reading anything there.Pin 10 ignition off is 0V
With your meter black wire on ground and the red on terminal 10 what do you read with the ignition switch off? Ignition switch on? Starter cranking?
Have you checked fuse #1 and cleaned it's terminals?
ignition on is 12.2 V
Cranking I get .2V in AC ...was getting nothing before??
Pin 9 and 14 at crank are giving 1.5 to 2 volts AC
I went back to my instrument wiring trying to trace the green/ yellow which turns into green black after the fuse.
Fuse is powering both sides.
Post by: The Mighty Gryphon on January 16, 2017, 08:44:40 AM
Post by: Laitch on January 16, 2017, 09:22:26 AM
Post by: gsxrpig on January 16, 2017, 05:22:37 PM
Pins 9,10,and 14 supply battery voltage. You should be taking readings on those pins on the 20V DC scale on your meter. You shouldn't use the AC scale on those pins.Mmmm. I was going off Bert's list and it is saying Volts AC 1.5 to 4V with starter running.
I am a bit perplexed with that as well.
If I set to 20V DC
Pin9
Post by: gsxrpig on January 16, 2017, 05:25:10 PM
Pins 9,10,and 14 supply battery voltage. You should be taking readings on those pins on the 20V DC scale on your meter. You shouldn't use the AC scale on those pins.Whoops..I was going off Berts list
pin 9-10-14 Ground to primary coils...starter running...Volts AC 1.5 to 4V.
I am having trouble getting my head around that one.
If set on 20V DC
pin9 9.5-8.6V
Pin10 10V
Pin14 9.4 V.
Post by: gsxrpig on January 16, 2017, 05:43:02 PM
Do you still have an clutch switch? It may be shorted.Hey Laitch.
No I eliminated the instrument cluster but kept the neutral light with the 4 relay setup.
So have also eliminated the clutch switch with that.
I went back through my instrument wiring yeterday to double check everything and it seems ok.
I thought I was in the clear with the clutch and Gear positioning features from a post I had months ago with RBM and Inge K.
I replaced the switch blocks with GSXR ones. So i used right hand switchblock wiring.
Green 12V feed to kill switch with Green and Yellow trace getting power with the kill switch off or RUN
Starter button is giving power to Black with yellow trace.to feed starter relay and ICU.
Thanks for the feedback.
The PO told me it was a runner before the fuel related issues.
So I am trying to believe him, and am thinking I have got something wrong in my wiring indeed.
I have removed the BMU and Flasher unit under past posts from forum members.
Along with removing the instrument panel and both switchblocks to fit the Gsxr front end I have put on.
So a lot of wiring changes have been made so I am happy to take the wrap for it If I can find it :dunno2:
Keep the ideas coming please...happy to test retest and experiment.
Post by: Laitch on January 16, 2017, 07:14:25 PM
Pins 9,10,and 14 supply battery voltage. You should be taking readings on those pins on the 20V DC scale on your meter. You shouldn't use the AC scale on those pins.I understand gsxrpig's reasoning. It looks like Bert is calling for AC readings on pins 8,9,10 and 14, and gsxrpig's readings seem to be close to conforming.
Ignition Control Unit chart extract.png (33.3 kB . 576x43 - viewed 450 times)Take your AC reading at pin 8 on the ignition control module, just for grins, gp. :yes
Post by: gsxrpig on January 16, 2017, 07:25:20 PM
The way I read Bert's ICU chart he is calling for AC readings on pins 8,9,10 and 14.These are my AC readings
Pin 10 ignition off is 0V[/size]ignition on is 12.2 VCranking I get .2V in AC ...was getting nothing before??Pin 9 and 14 at crank are giving 1.5 to 2 volts ACI went back to my instrument wiring trying to trace the green/ yellow which turns into green black after the fuse.Fuse is powering both sides.
Pin 10 on my bike is Green yellow trace.
Which is giving me 12V but little AC under starter??
Post by: gsxrpig on January 16, 2017, 08:29:42 PM
I disconnected the AFM. The temp sensor and the TPS.
Crank the bike..
For the first time I get a light from my Noid test light.
It is not a pulse..it lights upon letting go of the start button?
Reconnect the AFM...light there.
Reconnect the tps....light there.
BUT connect the Temp sensor ....and the light disappears again.
I have terminated the violet with black trace wire that normally feeds the warning light on the dash. But had thought this would cause no issue.
Sensor did respond to temperature change but was reading in the high end f the resistance chart?
So still no pulse but maybe a point in the right direction??
Post by: Laitch on January 16, 2017, 09:07:23 PM
These are my AC readingsFirst off, I can't tell whether you are making statements or asking questions when you use question marks so—no loss to you—I'm going to drop out now because it's making my eyeballs throb.
Cranking I get .2V in AC ...was getting nothing before??
Which is giving me 12V but little AC under starter??
But first:
Can we agree that your AC results for pins are within spec on Bert's chart 9,10, and 14?
Based on info you've provided, the only reading outside the chart's specification is the Pin 8 ignition module reading which is too high. Can we agree on that?
Is that "was getting nothing before??" a statement or question? It's an indecipherable statement in my book. I'm only concerned with what is happening now getting now.
"Which is giving me 12V but little AC under starter??" That is another puzzling sentence construction. I can't decipher that at all. It's too late for cafe cubano or I'd use that to translate. :giggles
"trying to trace the green/ yellow which turns into green black after the fuse." Where does the gn/sw wire go? Where does the ge/gr wire go?
It's an encouraging sign that you're getting a different reaction when something is disconnected, but using phrases like "reading on the high end of the chart" have no value to me. I need descriptions to be exact.
Post by: kennybobby on January 16, 2017, 09:49:51 PM
It should read a value close to that shown in the chart for your ambient air temperature, like a thermometer. My guess is that you will have a very high resistance or no continuity at all--did you put teflon tape on the threads?
When you say you terminated the other wire from that sensor, how do you run the radiator fan now without that input to the temperature relay module that was in the ebox under the tank?
Post by: Martin on January 16, 2017, 10:10:29 PM
+1 Kenny looking like a bad earth or Teflon.
Regards Martin.
Post by: gsxrpig on January 16, 2017, 10:30:33 PM
It sounds like you have a bad ground at the water temperature sensor. Measure the resistance from the L-jetronic connector pin 10 to chassis/ground (while disconnected from the L-jet).Hi Keenybobby thanks for the reply. very helpful.
It should read a value close to that shown in the chart for your ambient air temperature, like a thermometer. My guess is that you will have a very high resistance or no continuity at all--did you put teflon tape on the threads?
When you say you terminated the other wire from that sensor, how do you run the radiator fan now without that input to the temperature relay module that was in the ebox under the tank?
Reading 1164 at pin 10 with ecu disconnected. About 35 degrees here today. But the bike would be a little lower in temperature.
Yes i did have thread tape on the sensor but removed it after the testing I did last week. One thing was when I put the new O ring in the coolant pipe stub I put some gasket sealant on as well. It had a bad leak when I bought the bike. Maybe this is creating a ground issue. But continuity to the ecu is good and back to the sensing sw unit in the wiring box is also good.
The wire I terminated was to the warning light. the fan is still connected. the sensor is still connected to the sensing sw unit in the wiring box as well. Got rid of the light as I have a gauge now. I have tried hooking that wire back up to my led test light but nothing changes.
Post by: gsxrpig on January 16, 2017, 10:44:48 PM
Based on info you've provided, the only reading outside the chart's specification is the Pin 8 ignition module reading which is too high. Can we agree on that?
Is that "was getting nothing before??" a statement or question? It's an indecipherable statement in my book. I'm only concerned with what is happening now getting now.
"Which is giving me 12V but little AC under starter??" That is another puzzling sentence construction. I can't decipher that at all. It's too late for cafe cubano or I'd use that to translate. :giggles
"trying to trace the green/ yellow which turns into green black after the fuse." Where does the gn/sw wire go? Where does the ge/gr wire go?
It's an encouraging sign that you're getting a different reaction when something is disconnected, but using phrases like "reading on the high end of the chart" have no value to me. I need descriptions to be exact.
No we can't agree on pin 9,10 and 14 being in Bert's range. The AC on pin 10 is .2. Not 1.5 to 4V. I don't get that reading at all.
Now your confusing me. I was chasing gn/ge and gn/sw! I thought I was!
Sorry to confuse you Laitch.
Not my intention, pretty close to losing it with this bike. The question marks is a habit I have of placing a particular"I got no idea left" emphasis on a statement.
Post by: kennybobby on January 16, 2017, 11:20:22 PM
The ICU closes the circuit for the fuel injection relay that supplies the voltage to the injectors. It should do that both during running and when the button is pressed.
Check to make sure you have the load shed relay and the fuel injection relay in the correct circuits. Also the FI relay has 5 terminals but all the others only have 4.
Post by: gsxrpig on January 16, 2017, 11:43:12 PM
I am thinking ICU as well although I have no prove. I think I have sourced one but will take a few days to get here.
The Noid light will only light upon releasing the start button. At no other time. And only with the temp sensor taken off.
The load shed relay and the fuel injection relay on my bike as well as the horn relay are all the same type. All 4 pin and the wiring seems to to be correct to match. Mine is a 90 model Lt so there may be a difference to earlier models. I have tried swapping relays.
Post by: gsxrpig on January 17, 2017, 12:52:46 AM
Right.
First positive sign.
I decided to put everything back on and give it another attempt. After days of stripping wiring.
I left the temp sensor off all together.
For the first time since getting the bike it fired.
Started but stalls out very quickly.
Reconnect that temp sensor and it will not start at all...not even close.
Disconnect again and it goes back to starting.
Man i needed that bit of inspiration.lol
To test what was happening I connected injector 4 lead to a noid test light.
That light is evident only when releasing the start button at no stage before or after.
So the injectors must be letting fuel past on release of the button and now the bike has fuel to the plugs. But not enough pulse at the injectors to supply follow up fuel to keep it running.
Ideas anyone?
Post by: kennybobby on January 17, 2017, 06:42:29 AM
Is the noid light measuring on the injector supply side or return side? Is it just a 12V bulb grounded on one end with the probe on the other?
Your testing seems to show the green/red voltage is exactly opposite of the schematic. There should be no voltage on that line unless the starter button is pressed or the bike is running, at least on the 5-terminal FI relay bikes. Don't know if yours has a different schematic since you say it is 4-terminal relay.
Post by: gsxrpig on January 17, 2017, 06:12:00 PM
I will have to go check Green and Red at pin 9. I thought it was testing 12V only on pressing the starter button.
Yellow and grey pin 12 is the ground supply.
After replacing the ECU on the weekend I have eliminated the ECU and thinking the signal from the Ignition may be to blame.
I bought a second hand Ignition unit last night and it will take a few days to get here.
The water temp sensor is obviously causing problems and I have had one on order since last week.
I don't understand the tests for the ignition control unit. Pin 10 is a definite cause for concern.
It has 12V feed with ignition on.
But when doing the test from Berts chart when the starter is engaged the volts is .2. Testing in AC as on the list, this should be 1.5V to 4V.
The Mighty Gryphon said the tests should be done in DC volts.
So I am stuck at that test.
For some reason the signal is getting to the injectors only when I release that start button.
Probably a bad thing but if I press the start button after the bike starts I can keep it running a bit longer as the injectors are spiking a bit more fuel into the system.
Post by: The Mighty Gryphon on January 17, 2017, 06:52:22 PM
As far as DC vs. AC readings. Some of the terminals have both on them at various times. I will defer to Bert's chart for his readings. The reason for asking for the DC readings was to see what was happening to the 12V connection at pin 10 of the ICU. A bad connection somewhere could possibly interfere with it and disrupt the operation of the ICU.
As far as the temperature sensor, an easy test would be to get a 1/2watt resistor with the same value as a cold sensor and connect it between the sensor wire and ground. That would simulate a good sensor to the ECU.
Post by: gsxrpig on January 17, 2017, 07:02:43 PM
But I think at me not you Mighty Gryphon.
You have been here from the start mate. Don't give up on me yet.
Getting close. Was good to hear it start.
That pin 10 is a problem I agree.
I am happy to do any test you give me.
On the DC side that voltage is there so I will try and trace it back wards again.
I will try the resistor as well.
Thanks for the help again.
I think Laitch has given up so I would appreciate your help still!
Post by: kennybobby on January 17, 2017, 11:43:01 PM
It's difficult to troubleshoot from a distance if custom modifications to a harness have been made and there is no schematic for reference.
At least you know the L-Jetronic is likely okay due to the box swap, so the issue is on your bike, and the weird action of the temp sensor and the 12V power is a good clue.
The noid light i have no clue how it works. i would use a voltmeter on DC to probe between the backside of the injector connector and chassis ground. The green/red wire terminal should read battery voltage during the time when the FI relay is energized, i.e. during starting and while running. The other terminal with yellow/green should read battery voltage or something close to zero when the injector is firing. The other place you could see this is on the right hand side of fuse 6. Pull the fuse and measure DC volts between the right fuse socket and chassis ground, before and after pressing the start button.
You seem to have battery voltage during times when it should have none, and vice versa.
you are getting closer to solving this, hang in there...
Post by: gsxrpig on January 18, 2017, 12:05:09 AM
I have stripped the wiring from ecu to the injectors because something weird is going on alright.
I am getting 12v on Green red when cranking at the ecu and the injectors.
But also 12V on the yellow grey when cranking.
I put the probe on red and green and other probe on yellow and grey and I get a continuity beep. This can't be right can it?
i am close to finding the Gremlin I think. Keep the tests and advice coming, please.
My model is an LT so I am pretty sure that the BMU, Horn and fuel relay are all the same and interchangeable. Small relays. Different form the RS models...I think. The fuel relay doubles up the green and red wire on pin 87.
It is bloody hard to troubleshoot from a distance, I am grateful for the help.
I try and put my results up so to keep everyone up to date.
red is pin 30. green yellow is pin 86. yellow brown is pin 85.
Just inspecting again. Had 1 injector still connected so the continuity was going through that injector...Sorry got a bit excited.
I have no clue again..lol.
As for the 12V...I think that is normal, until the ecu sends the earth signal to open the injector. But why that is not happening is the million dollar question.
I have gone right back to when i replaced the ignition. Would this cause an issue?
Sorry above that should read Load shed relay, Horn relay and fuel injection relay.
Post by: kennybobby on January 18, 2017, 02:06:25 AM
Quote
I have gone right back to when i replaced the ignition. Would this cause an issue?
Post by: gsxrpig on January 18, 2017, 05:33:07 PM
I replaced the ignition with a simple 2 position switch.
Red is the feed wire. turn ignition on to feed Green and also Grey/Blue wire.
I have eliminated the Grey wire as it feeds the Bulb monitoring unit which is also eliminated.
Very strange that the injectors only get earth pulse on release of the start button.
I have the Green from ignition switch directly feeding 12V to the kill switch, then Green yellow feeding from the switch in the run position. The start button is Black with yellow trace to feed ignition control unit and start relay.
Hopefully something stands out as incorrect!
Post by: kennybobby on January 18, 2017, 10:27:24 PM
You left out mention of the wiring from the green/yellow from the kill switch--has that been changed? It should go to pin 10 of the ICU, to the coils, to the fuel injection relay, and to fuse #1.
The output of fuse#1 changes to green/black and feeds the clutch switch and then back to the starter button. The output of the starter button changes to black/yellow and feeds the starter relay and pin 4 of the L-Jetronic. The starter relay coil is grounded by a brown/red wire to pin 11 of the ICU.
The fuel injection relay coil gets grounded by the yellow/brown from pin 7 of the ICU, at which point power is applied to the L-Jet pin 9 and the fuel injectors high-side.
The green wire from the ignition switch also runs to the load-shed relay which supplies power for the headlights.
i would make a sketch of what your wiring actually looks like and compare it to a sketch of what it should be--maybe then you can determine where the wiring error has occurred that is causing the weird action.
i would recommend that you sign up on Bert's k100 forum, there are a lot of blokes from aussie on that site--and someone close to home would ride over to help you for a pint of beer or two...
Post by: gsxrpig on January 18, 2017, 11:15:40 PM
Black /yellow goes from switch to ignition control pin6 and also starter relay. Then from starter relay it goes to pin4 of the ECU. I haven't changed that wiring from factory but wondered if I had used the right wire to connect to the starter button.
Green and yellow does feed fuse 1. then onto pin 10 of the ICU.etc. etc, But I have eliminated the gear positioning and clutch switches. So that 12V safety feed back to the starter switch from those 2 features is not there.
I simple supplied 12V full power via green from ignition to one side of my kill switch. I would think the bike wouldn't crank if I had not done that step right.
A question. When I have just disconnected the temp sensor will the bike normally start or is the ecu just blocking the injectors for protection or similar?
Same with the clutch and Gear indicator switches...Does the bike crank if these aren't in the correct position on a standard bike or does the bike crank but stop injector flow?
Yeah. I have tried contacting a few locals, but It is a different breed to my normal bikes so don't know a lot of Bmw riders. Beer supply is never a problem...in fact normally leaving before complete intoxication is the problem.. :falldown: [size=78%] [/size]
Post by: kennybobby on January 19, 2017, 06:52:03 AM
A question. When I have just disconnected the temp sensor will the bike normally start or is the ecu just blocking the injectors for protection or similar?
Same with the clutch and Gear indicator switches...Does the bike crank if these aren't in the correct position on a standard bike or does the bike crank but stop injector flow?
1. i haven't tried disconnecting temp sensor on L-jet, but on Motronic it won't start without a good temp sensor. It may be true L-jet too, and your test results seem to point that way.
2. It won't crank if clutch switch is not in correct position on standard bike.
You will only get 12 V to the injectors thru the FI relay when you push the starter button (or the bike is running on it's own). The 12V power will be cut when you release the button, but this is not the same as saying that the L-jet is grounding the yellow/green return from the injectors. Absense of voltage is not the same as grounding. The wire color is yellow/green right, you keep saying yellow/gray, which is very confusing?
Did you ever try the resistor test--to replace the temp sensor with a resistor, any value from 500 to 5000 should work. One end connects to the violet-green going to pin 10 of L-jet, the other end of resistor connects to ground.
Post by: gsxrpig on January 20, 2017, 08:25:10 PM
Turns out my wiring was correct. Sorry for all the confusion with colors. :clap:
The old girl lives! :2thumbup:
Thanks for the help.
Also
The mighty Gryphon
And even Laitch... :popcorm
always hard to try and relay the info online, especially when frustration sets in.
Anyway we got there in the end.
If anyone is still reading and hasn't jumped ship.
Got the second hand Ignition unit yesterday....plugged it in and the noid light lit up like a xmas tree. For the first time since I have had the bike that earth pulse was working.
Initially flooded out but got it going after the usual fixes and she fires up well now.
Smoked heavily but it hasn't run for 4-5 years so to be expected with all the work that has been done to it.
Need to balance the carbs and tidy up.
Incidentally that is with the temp sensor plugged in.
I will replace that when the new unit arrives, it smells a bit rich , which may relate back to that sensor. Still a question mark on the temperature sending unit that I am about to look into. Seems someone has been there before me with writing on the underside of the relay.
Post by: Laitch on January 20, 2017, 09:04:28 PM
Thanks for the help.I think thanks ought to go out to Bert Vogel, too, because his troubleshooting chart was spot on. At reply #14 in this thread, gsxrpig was stalled by the lack of injector pulsing. He checked the AFM values and according to the chart, his values were not entirely out of line with a functioning AFM even though one was !5% lower than the lowest value. That could have been his mismeasurement given the circumstances. The problem AFMs in Bert's AFM chart had two or more skewed values. Bert's chart indicates the next step was to consider the Ignition Control as the problem but it took until reply #28 to start with it. Gryph was down with that unit being suspect too. When the pin #10 value was bad, that should have convinced all of us and stopped the backtracking.
This thread has taught me not to get sidetracked by the handwringing and weird language I'm reading; instead I should pay attention when an experienced wrencher like Bert Vogel has laid out a solid approach to the resolution of a problem. I'm pleased gsxrpig brought this to the forum in the way he did.
Post by: The Mighty Gryphon on January 20, 2017, 11:03:59 PM
:clap:
Post by: gsxrpig on January 22, 2017, 07:50:08 PM
I nearly didn't reply and if you go back through Laitch's comments maybe that will give you an insight into why some people may take some comments the wrong way and just not bother leaving a reply. If I get help I will always be grateful and always pass on my knowledge to anyone that asks...unfortunately not much on Bmw's at the moment.
I agree, Berts chart is sensational!
However when I threw in a LOT of variables sometimes further investigation is required to nail a problem down.
Firstly I was assured by the PO that the bike was a goer when parked, something now I find extremely hard to believe.
I have ripped out the entire ABS system from the bike and there was always a chance something had gone wrong there to affect things.
Removed the BMU and indicator set up.
Replaced both switch blocks with Suzuki ones. Removed the ignition and put in a kill switch.
Removed the instrument cluster along with the Gear position indicator and clutch safety features.
Not to mention have the entire wiring system out of the bike twice.
Any small wiring I had done may have come back to haunt me.
So checking and eliminating any issue in my wiring had to be done to ensure My work wasn't affecting Bert's chart.
Along the way I found issues with the AFM, temp sensor and a faulty Temperature sending switch but thankfully my wiring is good and not causing problems with any components of the bike. I have learnt a lot about the Jetronic and the Ignition control unit. The way the Germans do things is much different to the many Jap bikes I have worked on.
So would I do things differently...NO.
I am new to Bmw bikes so I don't have the contacts to randomly swap parts over with a mate. And this build as every other one I have done is on a budget! So randomly going out and replacing things before I am convinced they are faulty is just not an option.
Hindsight is a wonderful thing Laitch...sure if I had the ignition control box I would have tested it the same day as the ECU test. Probably would have swapped the AFM as well if I had one. But as crazy as you think I am, I am confident of riding the bike and not having issues with electrics down the road.
I thank everyone that has commented on this post. I for one don't think it was a simple one with all the things I have changed on the bike.
Great forum with excellent advice as well as excellent information at hand.
I hope as on other forums I am on, that I can help someone out of a bind one day.
Hopefully I get things tidied up soon and can get this project finished and get back on the road. Been 8 months between rides.
Post by: kennybobby on January 22, 2017, 08:31:57 PM
There's plenty of riders down your way in q'land, seems to be a great bunch to hang with. Post up a picture when you get her done.
Post by: gsxrpig on February 02, 2017, 06:39:19 PM
Post by: Filmcamera on February 02, 2017, 07:26:29 PM
Post by: jakgieger on February 02, 2017, 11:01:46 PM
One of the reasons that I am here is that when I was 16, I built a truck from three trucks, with a punch, screwdrivers, hammer, box end wrench set, and a handy man jack. I was able to do this with help from older and wiser mechanics with pointers as needed. When I frustrated them, they did not tell me that I was a wanker. They were able to communicate with a look, by not answering, by intelligent sarcasm, or by QUIETLY demonstrating the necessary actions. I have buried four of those mechanics now. They instilled a love of mechanics in me, and I attempt to pass this on.
Everyone who comes here realizes they have an older bike that will require some mechanical ability, maintenance, and patience. Zalle had me wondering today :hehehe :hehehe , but if he sticks with it he'll figure out that a little tlc now will save much grief later!