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CCMH
09-24-2012, 12:13 PM
Ok guys, here's one....

DD Series 60 on my coach, cruise control shuts down on its own. Reset the cruise then after about a minute or so, it disengages on it's own. Thoughts????

Coach Pro LLC
09-25-2012, 04:44 PM
TPS or "Throttle Position Sensor"

If the Jake fails at the same time as the cruise I can guarantee it (or as much of a guarantee you will ever get from an RV Tech. Haha)

The TPS is a small box attached to the side of the foot throttle pedal. It is basically a potentiometer that reads the position of the pedal, and sends that info or count to the DDEC, and then to the injector rack. It "reads" 0% to 100%, with 100% being full throttle and 0% being idle.

If the DDEC does not see 0% throttle, it will disengage the cruise (and the Jake). This is the same as working normally on cruise and you accelerate with your foot.

As corny as it may sound, I would wait for the cruise to fail and then "thump" the side of the pedal with your foot. If you check you will see the TPS attacked under the pedal. You could also try this on Jake for the same test. If that corrects or changes the problem, I would suggest changing out the TPS.

Another possibility is that the carpet or mat is too tight to the bottom of the pedal forcing it forward just enough to move the TPS from the 0% mark. This is a long shot but I have seen it.

The TPS is made by Bendix and would likely have to be ordered. I do not know the price but I would guess around 150.00. It has 4 screws and a molded wire connector.

Other possibilities are the cruise switch itself, the cruise relay and on and on, but the TPS is fairly common and easy to test before spending expensive diagnosis dollars.

Hope that helps! If you have any questions feel free to give us call.

Safe Travels,

Pat Sprenger
Coach Pro LLC
800-918-7170

nrhareiner
09-26-2012, 03:28 PM
I have had almost the exact thing in my coach. Jake and cruise control would stop working together. In my case problem solved by disconnecting the ecu cable at engine and cleaning the pins. This was done 18 months ago and has solved problem since. Hope this helps.