Cruise COntrol Stuck On.

[clubagreenie]

Just returned from day trip to Nowra and just after coming to top of Mt Ousley suddenly couldn't slow down tapped brake and nothing, hit CC button to power off, still nothing. So into neutral and shutdown. Pulled over and had a look.

Checked cables and nothing stuck but CC cable was pulling throttle open due to the vac diaphragm being held back by -ve pressure in chamber. Disconnected the CC cable and was ok to drive. Was too hot to reach under and pull hose to release pressure and diagnose there and too dark now to look at.

So clearly it has suction as it stays on even w/out power but what would be the possible causes of holding vacuum. Blockage in hoses? Elec issues on valve?

Thanks for suggestions.

[simonl8353]

..bump this thread here.

This is concerning, I've never heard of this ever before. Hope you can find and inform us of the cause.

[Scouse]

Initially I would have thought it would be a dodgy brake switch but the main on/off should have killed the system.

It could be a sticking diaphram/actuator - have you removed the hose yet to see if it returns to the idle/off position.

Other than that, it might be a sticky exhaust valve in the pump or a fault in the ECU.

[clubagreenie]

Update: Left the diaphragm in "on" position and when I got with the program and checked it yesterday afternoon it had relaxed back to off. Not sure if it's leaked down overnight or turned itself off.

Is there a way to activate the CC with engine on (cable disconnected) for diagnostic purposes?

Only one fault code I have ATM is 0349 camshaft position sensor.

[clubagreenie]

Further to this, haven't been able to replicate the issue. Haven't been able to make it work again. Light works on dash switch, but won't hold speed.

Any suggestions on where to start with fault finding, especially on the electrical side. The vac and mech side is the easy part. Need to work out the pins on the elec connection at the pump/vac unit.