Renewing ABS System

[jacksdad1963]

Next job on my old k1100lt! My bike has already had some of the ABS removed, the pump things on each side of the bike are missing and the rear sensor is also missing, just the end of the wire is there!
So, how do i go about renewing the rest of it please? The main control unit directly under the seat is still there, it has steel pipes going forwards and some electric wires on it. It appears that the front brake lines run into it, but looks like the rear is already removed. I don't want to risk having the brakes fail or lock on! So, what is the correct way to get rid of ABS completely? I have a lot of surplus lines and wirinh that can go! Thanks, Mike

[Scott_]

You list your bike as being a '95 in your sig line. That tells me that you have ABSII, so you will not have "pump things" on each side. Those were the old ABSI style.
The "main control unit" that you say is under the seat, is THE abs system for your bike--pump, and all.
Others have removed the pump assy and then have either, 1) connect the in/out lines together, or 2) re-pipe the brake lines from the master cyl locations to the caliper hose connections.
There is a multi-pin plug on the forward facing side of the unit that you can unplug.
Then other than that, on the rearward facing side there is the power connections. There will be 4 wires. 1 +Red(direct from battery un-fused) 1 -Brn and 2 pump relay wires(Ylw/Red--Red/Blue) that will end up back at the multi-pin plug.
The cover to access these power connections slides upwards. If someone else has already been in it, there may be a hole drilled in the cover to access the release catch. If you don't care how it looks just pry it off......... :dunno2:

Disconnect/remove the wires from the terminals(or just cut them without pissing with the cover), insulate the Red one so you don't short it out, and take the stuff out.

Disclaimer-----this is all just my opinion. What you or others have already done to your factory installed equipment is totally on you. If you don't have MOT inspections you should have no issues. Just beware if you do have them or sell the bike to someone that does have to, it may not pass.

After this is the interwebz, anything found here HAS to be true...... :hehehe

[mystic red]

Yep, if it were mine, I would fix the ABS, not remove it.

[Zipster]

Rear sensors are cheap on eBay and there's an ABS2 modulator and brain unit on EBay.co.uk at the moment if yours needed replaced. I'm with Mystic Red on this one - fix it. It probably easier to fix than you think and probably cheaper too.

I had to replace my modulator and got one from David S Walker who's on this forum too. He'll stand over his parts and can be relied upon. Anyway I whipped the old one out and stuck the new one in, bled the system and it all worked great. Give it a go!

[ljjohns]

FWIW, I've had a few events where the ABS systems (the ABS II on a KllLT and the integrated system on my K12) saved my bacon. I'd urge repair.

Larry Johnson
El Paso, TX

[Grim]

95 didn't have the servos everything is under the seat.
Fix if you can.

Mine was fried in every way imaginable. Some moron didn't hook the main ground back up and it pulled ground through the ABS burning up the harness brain and probably the servo. $2800 beater bike I couldn't justify the expense. I would need a whole new main electrical harness (it's part of main). For the bike, brain with servo and then see if the sensors were damaged.

Before gutting it get the warning lights flashing and there is two relays you need to pull to kill this lights on I know is blue but I can't recall if the second was. When they are flashing you can feel the relay clicking.
I made up a couple hard lines to by pass the servo and pulled the old hard lines out. On the front there is junction and I just installed a line to loop it back to the junction we the hose at the top of the radiator.

Rear is super easy. Just remove the lines going to the servo and bent up a new ward line directly from the master to the hose.

I pulled the harness plug up and stuffed it under the tank after taping the plug up.

The servo being out of the loop made for a very firm lever. Rear doesn't feel a whole lot different.


Again if it's just a sensor fix it and keep it functional.

[jacksdad1963]

Sounds good! I thought some parts had been removed, for example, the switch in the handlebar cover has had all the wires removed, there's a connector under the tank near the rh side panel that has a loop of wire joining the 2 ends together, theres a spare earth wire under the rh side panel, and the front brake sensor is missing, just got a length of cable stopping at the mudguard....
I need to see another bike thats complete!  :dunno2:

[Zipster]

Mike, I'll take a couple of photos later and post them here. I'm no expert and I have no clue about wiring under the tank but I'll do my best for you. Just so you know, I have a spare front sensor test I bought as the PO told me mine was damaged when in fact mine was fine and the ABS brain was fried! I can let you have it for £35 which is what it cost me, if you're interested. Cheers, Al

[David_S_Walker]

Sounds good! I thought some parts had been removed, for example, the switch in the handlebar cover has had all the wires removed, there's a connector under the tank near the rh side panel that has a loop of wire joining the 2 ends together, theres a spare earth wire under the rh side panel, and the front brake sensor is missing, just got a length of cable stopping at the mudguard....
I need to see another bike thats complete!  :dunno2:

Hello,

Thanks Zipster for your kind words! (Again)

Let me know if you need a ABS brain - I have two which were removed from working ABS machines - Currently listed on eBay at £50 delivered but if this is what you need I am sure I could lowered the price for a forum member although they are quite heave so postage is a bit salty. I also have rear sensors for a late bike but it is still in the caliper as I don't want to damage them by removal but I sell the calipers complete for £20 delivered. I do have a load of solid brake lines which are waiting to be collected by the scrap man but it doesn't seem like they are the problem in your case?

Best regards,

David

[Zipster]

What it looks like under your butt! The combined modulator and brain unit is at the bottom.

The blue diagnostic plug.

Rear sensor and ABS ring

Front sensor and ABS ring.

Dash lights - both ABS lights should flash together on start up. If they flash alternately, you either have a low voltage fault which should reset on a restart or a brain fault which won't! Once you've both wheels rolling above 4mph, you should hear / feel a clunk under the seat and the ABS lights will go out. If they don't then you have a fault. You can diagnose a fault with a simple 12v LED - one end in the centre hole of the diagnostic socket and the other end grounded on the frame and count any "offs" rather than "Ons" to give you your fault code. You can decide how to fix it from there!

[Zipster]

One LED diagnostic light - one wire to the centre hole in the diagnostic socket (remove the blue protector cap first) and the other end grounded on a bolt into the frame.

[jacksdad1963]

Ok guys, many thanks!
I seem to recall riding the bike home, that the 2 warning lamps were flashing alternately all the way...35 miles
The front sensor has been bashed by the disc at some point, its damaged so maybe that was the fault? Luckily its the only part I've removed along with the warning lamp bulbs: looks like I'm going to have to remove the clock housing again! I can do it with the fairing in place, I just remove the upper bits and struggle :clap:
The RH side of the clocks/pod isn't lighting up and I've replaced all the green bulbs for standard ones, so might as well pul it apart and fix the lot!
Once I've rebuilt things I'll post some pictures of the modoified wiring.... :yow

[jacksdad1963]

OK, I've got some pics, just need to find out how to upload them!
I've done the test, LED bulb live to centre plug, and neg to earth: the led lit, but wasn't as bright as when connected to a direct 12V live?
Things are looking better already!  :clap:

[jacksdad1963]

here we go:

[Zipster]

When the LED lit it would have started to flash. The number of times it flashed off is the number of your fault code. Mine was fault code 7 which is a ECU /brain problem. There is a list of what the codes are somewhere here in the lieberry. A steady LED means no faults but you should have one if the front sensor is removed.

The blue plug in the first photo is like the plug on the sensor I bought although I haven't looked under the tank on my machine.

The middle pic looks pretty similar to mine.

I've seen a plug with a loop like that on my bike and I don't know what it's for so I left it alone. I don't think it's to do with the ABS.

[Inge K.]

I've seen a plug with a loop like that on my bike and I don't know what it's for so I left it alone. I don't think it's to do with the ABS.

It's a bypass for the sidestand switch.

[Zipster]

That would figure as my side stand has no effect on the bike running whether it's up or down. Does removing the loop fix that?

[jacksdad1963]

Thats good: all the sidestand gubbins has been removed! The only thing that works is the starter motor cutout, I need to pull in the clutch to start the bike when in gear, which is fine for me.
So, do I need to A/ switch on the ignition then B/ connect a lamp to the centre wire & earth? will this make the lamp flash as stated?

[Inge K.]

That would figure as my side stand has no effect on the bike running whether it's up or down. Does removing the loop fix that?

If you still have the female connector on the wire coming from the sidestand switch which also should be
found under the RHS battery cover, you can disconnect the loop and push these connectors together.

But keep the loop in the ducktail, the sidestand switch mechanism is a known trouble maker......
due to lack of maintance.

[Inge K.]

Thats good: all the sidestand gubbins has been removed! ............., which is fine for me.

Have that in mind the day you're in a hurry /have a brain fade......all is OK untill you meet the first LH turn.

Been there, done that, ....in the time before safety switches and self retracting sidestands
first LH turn was on a main road............spent two months on hospital.

[jacksdad1963]

Ha! I'm well used to the side stand on bikes, not had safety things on them for the first 30 years!
Anyway...I've just tried the test above, but with a multimeter instead of the LED: I got a solid 12.6V, which then went to about 1.5V, back to 12 the to about 3.5, back to 12 then about 5. Seems that the meter/voltage is showing something!
Its now almost midnight in Manchester, so I'll have another try in the morning: thanks again for all your input, I'll get it sorted with you guys helping me  :2thumbup:

[Inge K.]

So, do I need to A/ switch on the ignition then B/ connect a lamp to the centre wire & earth? will this make the lamp flash as stated?

About Reading the fault codes have a look at this: http://www.largiader.com/abs/absfault.html

[Zipster]

If you still have the female connector on the wire coming from the sidestand switch which also should be
found under the RHS battery cover, you can disconnect the loop and push these connectors together.

But keep the loop in the ducktail, the sidestand switch mechanism is a known trouble maker......
due to lack of maintance.

I'll take a look tomorrow - many thanks for the info. :-)

[Scott_]

The wires for the dash switch should be a black and brown, and the connector should be located under the front of the fuel tank.

[jacksdad1963]

Ok, getting there!
Found the plug under the tank, so just need to solder new wires to the back of the switch (shouldn't matter which way round...I hope!) and connect up, I've refitted the battered front sensor, just going back and putting bike back together, brew times over  :clap: