TEMPERATURE SENDER

[Schnellfahrer]

After several years of problem-less performing my 1995 K75 with 31K miles has given me several issues lately that  I fortunately could resolve.   However, I now have a cold starting problem that apparently is caused by the Temperature Sender, the one below the radiator and very hard to get to.

Before I start taking things apart I want to see if there is a way to test the sender. From reading the various comments on this topic on MotoBrick I understand this test is possible through Pin 10 on the ECU.  (?).  Where is Pin 10 pray tell and what do you do with it?

I am somewhat technically knowledgeable but certainly not overly so and in this case not enough.
I would very much appreciate any advice on this subject.  I will wait with the purchase of a new Temperature Sender until I am sure I need one as I am not looking forward to doing the replacement job.
Many thanks!

[Paul_Waterloo]

The ECU is the motoronic thing above the battery. Disconnect the pin and then you would do a measurement to ground. Considering I have not looked at the wiring diagram, I don't know 100% if this is true, but that is the basic procedure.

[Laitch]

The ECU is the motoronic thing above the battery.

The K75 and K100 2 valve motos use a Jetronic fuel injection control, not a Motronic engine management system like the 4 valves.

Download and read the flow chart and troubleshooting guide at the bottom of this page by clicking on its link, Schnellfahrer. It will explain how your moto's engine systems work and how several kinds of tests are performed including a couple of tests involving the coolant temperature sender.

[Paul_Waterloo]

Thanks for letting me know that I don't know anything. But at least I kinda wrote that.

[Laitch]

You're welcome.

[volador]

HAHA LAITCH SLAPPED!!

[The Mighty Gryphon]

Don't let it bother you.  I notice in your signature line that you have only owned 4 valve bikes, so you  have no experience with the Jetronic.

[volador]

Temp sensor on coolant 'T' into engine block test for resistance either sensor 'spade terminals' to sensor body measures ≅ 2.5KΩ @ 20°C

test pins 10 and 5 on the ECU connector plug under the seat for resistance measures ≅ 2.5KΩ @ 20°C
Flat blade screwdriver, 'lever forward' in the hole of the tool-tray to loosen ECU connector plug

check the wires from Pin 10 & 5 of the fuel injection control unit plug for open or shorts

Pin 10 - violet/green
Pin 5- brown

more about Jetronic diagnosis http://www.motobrick.com/index.php/topic,13440.0.html

[Schnellfahrer]

Thank all you guys providing me with advice on my starting problem.    It did turn out to be a faulty Temperature Sender.
It is quite an undertaking to replace it as the radiator has to be removed, at least partly, along with the fairing and hoses need to be disconnected.
If it ever happens to you make sure you get an OEM or at least a European made sensor.  I was assured mine was a Bosch but was emailed the next day it was made in China.  No thanks.    They then send me one made in Spain by FAE which apparently is a high quality copy.   Anyway, the Brick started up immediately after the operation.

Again, I appreciate everyone's assistance and good words.

[natalena]

Great you are getting the brick running.

Who are "they" that you speak of? It's commendable they were quickly forthcoming with the part origin, and got you a european made part. That's pretty good customer service and responsiveness.