dslpower

So I have been all over my truck trying to find out WHY the cruise wont work.

I have volts on blue wire at vacuum servo when on switch depressed (brake switch adjusted and working).
Speedo works below 10mph so I dont believe VSS is bad.
Servo swapped with working unit just to check(no help).
Cleaned contacts on switches. Still nothing.

Does the TPS have any part in the cruise system or is it only to control the tranny???
What about the ABS system?? would it be part of the cruise??
I know the ESS has nothing to do with it working, cause I drove a 4x4 model that the cruise operated properly with the ESS off the engine.

Everything else works properly WIF,WTS,alternator,A/C,grid heaters...Execpt for Lock-up, I have to do that with the mystery switch or no lock-up at all. Thanks ya'll.

infidel

Buy the diagnostic manual for your truck here https://techauthority.gltghosting.co...atalogId=10051 it's only about $12. There are about 40 pages on the cruise control, way too much to cover here.

One thing the manual doesn't cover is poor connections caused by enlarging female electrical connectors with a voltmeter probe.

b.lee

from what i hear its a TPS thing.
just my guess from reading others posts for a while.

gmctd

Checked for vacuum?

Sidewinder

The TPS DOES matter. When my TPS died the cruise stopped and then started working after the TPS was installed.
Not saying that is your problem but it is possible. From what I have read it could also be a vacuum line under the drivers side battery. Acid spills on it and causes a vacuum leak.

dslpower

Vacuum OK, should have added that on first post, line is good also. I always back probe the connections so no problems with the enlarged females

Thanks for the link infidel, just ordered the manual.

One other question... my tranny is modified, converter, vb, shift kit, What is the resistor (and where does it go) I have heard about??? Thanks Guy's