I cant seem to get my cruise working for longer that 15 min then nothing I try will make it work again. I bought a Kent- Moore J2958 tester and everything test out right. I have replaced all the components checked all vacuums spent a lot of cash and it only works , it seems to me like when its cool. That may be my imagination but I sure could use some helpful suggestions on what to test or look at. Thanks very much. BN

Is the brake light switch adjusted properly?

Joel

I believe there is also a vac switch on the brake pedal....

I put a new switch on and its adjusted. but when i hit a bump it will shut it off also which aimed me to the brake switch. I'm gonna try another new one and we'll see.

Aren't there two switches?

One is electrical and the other is vacuum?

no, 86 Chevy Scottsdale. There is A switch which rubs the brake petal shaft. Its pretty straight forward. I tried adjusting it way one way and way the other and still problems. That high dollar tester says everything is right and ok. Like i mentioned Ive replaced everything including the speed ometer .To make sure the the shinny spot for the pick up is new. If you can tell me something to look at I would be very thankful . I like what yall are saying so go ahead . thanks BN

I don't know if this helps, it'* from an '86 C10......

I always thought that cruise systems had a backup system.....your cruise actuator/servo uses vac right? If it did the vac switch was used in addition to the electrical switch on the brake pedal, in case either switch failed....




Click twice on diagram to make it bigger....

Im going to take another look. It mite be a day or two before I can get to it. What I have noticed is the system has to be turned off at the blinker switch. First start up I can get up to speed then turn it on then set speed and it does perfect until i hit brakes or come to stop. I should be able to get going again by hit resume but that one time after first start up is all I get. i can turn it off and on as many times as I want but it wont work again. Today nothing I could do would make it work. Im going to continue to work on this as much $ as I have tied up in it now. verses a aftermarket universal system. I have a new 350 crate engine in it now but it wasnt working for 3 yrs. before new engine. Thanks again and thanks for that diagram! B Nick

This isnt really quick but I wanted to tell yall I replaced every part of the cruise system I could even the speedometer. The cruise works perfect now. I think it may have been a pinched wire from turn signal arm down to cruise connections. Or the reflector in the speedometer. The cost of the parts was nothing compared to the aggravation of trying to figure the problem out. Thanks for all your answers and help.

You may have a bad servo.