Cruise Control Disconnects

[clubjoe]

After driving my 1998 C5 for about 30 miles the cruise control will disengage. Some times it will let me resume but then disengage again. The car will start surging slightly at this point. I checked the DIC but no errors are displayed in history or current. If I let the car sit for an hour I can use the cruise for about 30 miles again. I have heard that there may have been an update done to the PCM for a 1998 C5s and also that there was a common problem with the brake switch. I have made an appointment to bring the car in for service but I don't really want a run around. Has anyone come across this problem?

Thanks,

JOE

 

[c4c5specialist]

HI there,
What they will most likely try first, is a reprogram for this condition, if your car needs the updated calibration.
There were some cars that had this issue, and a reprogram of the PCM cleared up the problem.
After that, they will most likely check the brake switch to confirm that it is adjusted correctly.
Please let us know how you make out, and best to you, c4c5

 

[danl72]

Could there be a problem with the cruise control itself. I am asking because my brothers old Z28 had a problem like that and it was the cruise control that needed to be replaced.

 

[c4c5specialist]

HI Dan,
The systems are different, as with F car, you have a separate cruise control module. On c5, the function is controlled by the TAC module, which is the throttle actuation control.
This is why the calibration will help the condition.
Besttoyou, c4c5

 

[clubjoe]

Cruise Control

I took my car into the local dealer and waited for it. They really do not like this and went out of their way to make me wait 6 1/2 hours to do the 1/2 hr. job. They first off said there were no updates to the PCM listed by GM for a 1998. They then said there was no adjustment available for a brake switch so they had to replace it. So for $125. I now have my cruise working again and another reason to avoid dealers.

-JOE

 

[danl72]

Sorry to hear about the bad service at the dealer. Believe it or not not all dealers are that bad. The dealer I go to is very good. They do a good job and they don't take all day.