jkarner

I have a 96 12v manual- cruise control didn't work when I bought it. 218k. The light on the CC button itself lights up when pressed, so can I assume the button switch on the steering wheel is good and the wires up to it are still good? The CC does not engage at all not even intermittently.

I have been doing some reading on what to check, but I don't understand how to check for to do the vaccuum lines-details would be appreciated. Also any detailed help on how to check the brake switch and servo would be great and any other suggestions for checks I could do would be great. I am about to do a cross-country haul and need CC soon! Thanks for your help!

infidel

Feel along the vacuum line going to the CC servo under the battery for rot or disconnected.
I hardly bother testing brake switches anymore, just replace, $11 at Napa.

Hodge

x2. Mine had a leaking line, disabling the cruise. Friend found the leak with a smoke machine- if you can make smoke one way or another, you can follow the smoke to the vacuum leak.

jkarner

Infidel, I replaced the brake switch and it did not cure my cruise control woes. I am about the drive across the country and need to get this truck into shape so my foot doesn't fall off holding the pedal down for three days.

Where are these vaccuum lines that I need to check? The light still lights up on the steering wheel when I press the cruise button but when I go to set the speed it doesn't engage. I'm hoping I dont need to chase wires under the the steering column, but maybe that's a start too?

infidel

Simple way to check for a vacuum leak is to run the engine, shut down for at least five minutes then remove any vacuum line.
It should hiss, if not you have a leak somewhere.
A leak free system will hold vacuum for hours if not days.
If you don't have any leaks then the problem is likely electrical.

jkarner

Thanks Infidel, I am going to attempt to replace the actuator hose that broke off when I was trying to remove it today and then test the vaccuum system like you said. I'll keep you posted.

jkarner

Bill, I replaced the actuator hose today and still no cruise. I looked over all the vaccuum lines I could see under the hood and did not see any visible cracks/deterioration.

I did like you said and pulled a vacuum line off about 5 minutes after I shut the truck off and did not hear any hissing or air being pulled in, so I assume I have a leak somewhere.

Whats the best way to find this leak? I guess I need to probe around the transmission vacuum lines? How will I know if they are leaking? Can the servo itself be at fault here?

Thanks a lot for your help!

ET RAM

I use a vaccum tester for checking leaks. You apply some vaccum and the gauge will tell you if it is holding or leaking. You might try AutoZone to see if they have one that they can loan out. You leave a deposit and get it back when you return the unit.

The servo could be the problem. You need a manual to go thru the diagnostic tests.


Vacuum Tester