Removed valve covers and operated jake solenoid,it wll activate. Ran 12v to solenoid and it works. Adjusted all valves, injector preload and jakes. Have power at jake on-off switch. Cruise control does not work. Not sure where else to look for cause of problem. The truck is a 2000 Sterling LT9500 with Cat C10 and 8ll trans..
Check fuse for cruise. I would suspect it enables a second brake switch which disables cruise and enables retarders. Whether it's an air switch or a plunger switch on the pedal, I can't say.
I'd check clutch switch. If that is not the issue, I'd get a laptop on it and verify the throttle pedal goes to 0% when released.
Our sterling would do this till you turned the key off then we realized if you hit the cruze switch by mistake they don't work
Thanks Tyler, Ill try that. I also looked for a switch on the clutch pedal and linkage but found none. Accelerator pedal does not have one either. it only has a plug with wires going to ECM.
Even if that isn't your problem maybe the switch is stuck in the steering wheel of something along those lines