Thread: Cruise Control

Originally Posted by Stuart555

Hi guys....I am back...sorry to annoy you. My cruise control only works now and then and I have read posts about removing the ECU and carefully cleaning it to get it to work again.....problem is I don't know where the heck it is!! Even if I have to fit a new one, I still need to know where it is and if it is easy to access. Hope someone can explain it's location in terms a novice like me can understand. Thanks.

The cruise ecu and relay are relatively trouble free units. The usual culprits (don't ask how i know???) are the rubber hoses, vacuum actuator and the brake vent switch.

Rubber hoses (T-piece) - check for leaks. Suck at the long hose leading from the T-piece to the vent switch and make sure that you cannot suck through that. If you can, either hose or vent switch (common issue).

Actuator - make sure no punctures in the rubber capsule and that it will hold a vacuum.

Brake vent switch - unlike what some others may tell you, the vent switch for the cruise control has absolutely nothing to do with the brake lights. The vent switch does 2 things when the brake pedal is not depressed......earth the cruise ecu line, and maintain a vacuum as required.

Originally Posted by p38arover

If it's where I think it is, you won't need to remove the instrument cluster, just the two closing panels under the steering column.

......and you need to remove the air-conditioning pipe that runs horizontally below the steering column. Just replaced the cruise vent switch over the weekend.

Well Guys I am back and I am still having issues with my cruise control. What I have done: I have replaced both ECU and Inverter switch. Have checked and replaced faulty hoses. Have removed and tested brake pedal switch and all are good. After I replaced the ECU the cruise wanted to work because I could hear the relay clicking but as one of the hoses was split it would not work. Replaced that hose and presto! it worked! For a while anyway........now nothing....not even a click from the relay. I read somewhere that if you change the ECU you probably have to have it "flashed" by a dealer to get it to work. Any thoughts anyone. As travel regularly from Bendigo to Dandenong I would love to have cruise control again. Help.

No need for flashing the ECU on the P38.

Does the cruise control switch light up when it's on?
Apparently if it doesn't, it can cause intermittent operation of the system. Mine doesn't light up (too lazy to change the globe until I have another reason to go into that area) & I sometimes need to operate the main switch 'off' then 'on' to get it working.

BTW, do you have a copy of the diagnostic test procedure?

Do your stereo buttons on the steering wheel work? If not I'd say your not sending signals from the steering wheel to cruise ecu either!

The light on the Cruise switch lights up ok. I dont have a copy of the dignostic test procedure. The radio in the vehicle is non genuine and the control buttons on the steering wheel have never worked. I am told if I take it to someone who has the dignostic equipment, they can pinpoint the problem straight away.

Yeah it might point you in the right direction!

Hi guys!
Just an update on my cruise control problems.
I went to AMV in Ringwood to have a diagnostic check to find the fault only to be told that the diagnosis will not show cruise control faults. In frustration I told the guy what I have done to solve the problem and said I was at the end of my tether trying to sort it out. He quite confidently told me to forget the internet for solutions to my problems and give him the car for 2 hours and he guaranteed it will be fixed and won't cost an arm and a leg. I wonder??????