cc problem

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fjrlover

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Hey guys, last topic I started you helped very much and I appreciate it. Got the bike put together and it ran very good. Let me recap. I wanted to rerun some messy wiring and make some preriding maintenance. In doing so I blew up the rectifier and learned my lesson. So I got a new one from the factory and after checking the wiring I installed and instant gratification. So anyways, I took it for a ride and the bike ran perfect and the cc worked. So this past Friday I went on a good journey and to my surprise the cc did not work. But the lights on the buttons are lit up and the on led lights up when I turn it on. I got home from work today and decided to check into it. The only way I thought it would work is if I raised the tank so I could see the throttle bodies at work. I started the bike and put it into gear and raised the mph to 10, pressed the cc on and it held speed until I pressed the brake. Well, this is supposed to work like that so what the f!@#$%&**. Annoyed at what just happened I tried it again and not the same result. This time when I pressed the set button I seen the cable get tension like it was supposed to but it did not hold it in place. I am in dead water because I don't quite understand how the vac/servo unit works. It has to be getting the input otherwise it would not try. If you have any ideas and or things I can try please let me know. Or if I have to clarify anything.

 
The cruise won't work correctly on the center stand, there isn't enough load on the drive train so the cruise sees the speed command actions happen too fast and sets an error condition.

If you have intermittent operation but the LEDs always look correct you should be sure the tach connection is solid and then look for a sticking brake peddle or a voltage problem on the brake wire. If possible you need to monitor the brake wire voltage when the cruise doesn't set the speed.

 
One other possibility to explore (under the KISS principle).

Make sure that your rear brake light switch is not staying on.

It happens...

 
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well I checked the possible switch idea and the switch works great. Open when decompressed and closed when compressed. The rear brake is not on unless I compress the brakes. This may seem like a dumb question is there and where is the switch for the foot brake?

 
Well, look at the brake lights. Do they go out as expected? If so then the switch is probably OK.

But if the cc's monitoring of that switch is invalid (loose connection, bad splice, poor solder, whatever) that can cause what you describe. It HAS to see 12 volts on the red wire and it HAS to see zero volts on the pruple wire in order to set a speed.

But you have to ride-test. It won't work on the centerstand with the drivetrain unloaded.

 
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well I checked the possible switch idea and the switch works great. Open when decompressed and closed when compressed. The rear brake is not on unless I compress the brakes. This may seem like a dumb question is there and where is the switch for the foot brake?

The switch itself is attached to the brake pedal in tandem (behind) the physical connection that actuates the hydraulic brakes. And the prior suggestion to monitor the rear brake light is absolutely valid. The reason that I suggested it is that I (and others) have had numerous situations where the brake light sticks on due to minor "stiction" of the rear brake pedal. If the pedal can't return fully to "home position" the light will not clear, and the CC will think that brake is on.

 
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KEERISTE!!!!

When I saw "CC Problem" in the thread title, I immediately thought "cam chain".

I'm gettin' gun shy. May have to stay out of the Tech/Mech forum for a few days so my sphincter can un-clench.

 
When I saw "CC Problem" in the thread title, I immediately thought "cam chain".
I'm gettin' gun shy. May have to stay out of the Tech/Mech forum for a few days so my sphincter can un-clench.
Howie: Could the problem be that a little RUST has collected in the brake switch? :detective2:

Tell 'em what to do to fix it...

 
well I checked the possible switch idea and the switch works great. Open when decompressed and closed when compressed. The rear brake is not on unless I compress the brakes. This may seem like a dumb question is there and where is the switch for the foot brake?

The switch itself is attached to the brake pedal in tandem (behind) the physical connection that actuates the hydraulic brakes. And the prior suggestion to monitor the rear brake light is absolutely valid. The reason that I suggested it is that I (and others) have had numerous situations where the brake light sticks on due to minor "stiction" of the rear brake pedal. If the pedal can't return fully to "home position" the light will not clear, and the CC will think that brake is on.
Exactly what Fred said! What you need to do is try to get it to fail while the bike is parked. Slowly press the rear brake until the brake light comes on and then very gently release the pedal to see if it will hang up. Vigorously pressing and releasing the pedal might not show the failure. This is a very common FJR problem.

 
Cruise op/inop test CAN be performed on the centerstand, just not as complete a test cycle as one would hope for. The cruise will set on the CS, it will just quickly shut down as mentioned before, but it will tell you if the servo is getting a "set" signal or not.

 
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