Difficult cruise control question

[coug66]

I have been chasing this issue since I have had my bike. http://www.bmwlt.com/forums/showthread.php?t=27881 I would love the cruise to work and am baffled by this problem. I want to work on it over the winter so I don't miss riding by wrenching.

Problem my cruise will not activate.

The test fails at step 2.

1) With the ignition switch OFF, switch on the cruise control. Press and hold the cruise control switch to the SET position and switch on the ignition switch (LIGHT).

2) Release the SET button (LIGHT GOES OFF), move the switch to the RESET position (LIGHT).


This thread points to the idea that some tests share the same sensors.
http://www.bmwlt.net/ubbthreads/showthreaded.php?Cat=&Board=K1200LT&Number=135727&page=&view=&sb=&o=

I just bought a brand new (CC, screen, headlight, turn signal)switch assembly to eliminate this from consideration (the old one passed all my initial tests for continuity).

My question is; Is there another switch that shares the same input?

My light will not go off, no matter what I do ( except turning the ignition off)

Could someone else try a simple test by engaging the brake or clutch while doing the cruise test?

If you get the same result then It probably a stuck switch and I will go through all the switches to determine the culprit.

I think the shared output is my solution since the test is designed to tell which sensor is failing. I should not get this result from a stuck sensor?


Thank you for the help,


Ian

[RalphLT]

I held the clutch in and turned the ignition sw on while holding the set button then released the set button and the cruise light went off. Did the same with the rear brake and the light went off. Hope that helps some.

Ralph

[coug66]

Thank you,

This is a difficult one. What makes it more difficult, Is this just brings up the point that its probably not a switch problem?

The idea that the system works enough to have the set switch activated to start the test but once started you can't get the light to go off. I am wondering if the cruise brain or computer is bad?

It doesn't seem to be a bad switch just a bad cruise computer?

Is there a replaceable cruise computer assembly?


Ian

[RalphLT]

There is a Cruise Control Unit inside the left fairing, towards the front according to the picture in the parts breakdown. The wiring diagram shows all the switch inputs, speedometer, handlebar switch, and cruise light connect to the control unit. One thing to note, although it may be meaningless, the common wire from the cruise light as well as other instrument common connections go to a "Fuel Warning light control unit". I haven't found that unit in the wiring diagram; anything else funny going on within the dash?

[coug66]

I was wondering if you could help me again? Can you pull the fuse on the cruise control under the seat? number 12 and run the cruise test to see if it fails on number 2?



http://home.comcast.net/~ianlindner/pwpimages/cruise%20control%20fuse%20copy.jpg

If I think back I think I did not have a fuse firmly secure in the cruise slot. If I remember rite it was loose and did not seem to feel firmly connected.

I am wondering if its a fuse issue?

I don't even want to get my hopes up that its something this simple! :dance:

Ian

[coug66]

Pulled the fuse and the switch light goes out....

So another dead end.

Ian

[RalphLT]

There are 9 connections to the cruise control unit ( Clymers manual), 5 from the multi-fiunction switch, 1 from the front/rear brake light switches, 1 from the throttle and clutch switches, 1 from the speedometer, and one from the cruise control light. I think you have eliminated all but the speedo and light input/outputs. It would seem the logical answer is the control module. But not knowing the control module circuit it is difficult to say for sure.

Ralph

[coug66]

I took the plastic off the left side.

I disconnected the Cruise unit wire assembly and connected it to a used Ebay cruise unit.

The cruise test now past the 2nd test of turning the set light off when I released the set light.


test below

This procedure must be done exactly as follows while you monitor the "SET" light on the instrument cluster:

1) With the ignition switch OFF, switch on the cruise control. Press and hold the cruise control switch to the SET position and switch on the ignition switch (LIGHT).

2) Release the SET button (LIGHT GOES OFF), move the switch to the RESET position (LIGHT).

3) Release the button (LIGHT OFF), switch OFF the cruise control switch (LIGHT).

4) Switch the cruise control switch back on (LIGHT OFF).

5) Rotate the throttle against the throttle stop (LIGHT), release the throttle (LIGHT OFF).

6) Pull the clutch lever (LIGHT), release the clutch lever (LIGHT OFF).

7) Pull the front brake lever (LIGHT), release the lever (LIGHT OFF).

8) Push the foot brake pedal (LIGHT ON), hold for 5 seconds (LIGHT OFF), release foot brake pedal (LIGHT ON).

9) Rotate the rear wheel (LIGHT SHOULD GO OFF/ON).

10) Switch off the ignition.


Now my problem was how to install the new end of the cable to the throttle bodies?

I removed the old cruise unit and tried to dissasemble it to see if I could swap electronics new to old. I bust the housing cover getting the old unit apart. :( Bummer this was not the sollution. I didn't want to break my new unit trying to swap the electronics.


I then found a way to attach the new unit to the existing cable. No need to dissasemble the gas tank and half the bike to install the new cable to the bike.:rotf:

Bolted the new unit in, connected to the existing cable, ran through the test and it works!!!!

Passed all the tests listed above and I am back in action with 1 hours time and a $25 dollar cruise purchased on Ebay!!!!!

:dance:

[jzeiler]

Sounds like you made out like a bandit Ian. Thanks for posting with a solution to your problem. It will most likely help someone out in the future. Enjoy the ride.

[Kurtverbose]

You forgot to do a little dance between steps 4 and 5.