cruise control

2004 DODGE RAM

190,000 MILES

CAULIFLOWER

MEMBER
1 POST

After we start the truck the cruise will engage the first time but will only work until the truck motor works a little up a hill etc and then kicks out. Then the cruise wont work anymore until we shut the motor off and then the whole process above repeats itself. The motor is 5.9 diesel.

Nov 9, 2013 at 4:59 PM

KASEKENNY

✓ASE Certified Mechanic
18,907 POSTS

There are a couple of things that could cause this. First is a faulty servo or even a leaking vacuum line running to the engine.

We need to check this by checking the voltage going to the servo and find out if the ECM is commanding it off or it is just losing vacuum and disengaging.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

The next likely cause of this is an ECM but this sounds more like a vacuum issue.

Take a look at the wiring diagram below and let us know what you find with this but if it were me, I would look at putting a servo on it as this is the likely cause of this.

Thanks

Image (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Mar 20, 2022 at 8:12 PM

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