Cruise Control fault

[revdave]

In case anyone suffers from a similar issue this may help.

I had a brake light blow yesterday. Stopped engine while parked up for school pickup but when I drove off again the cruise control wouldn't set even though the dash light was illuminated.

At home, changed bulb and then was out again today but still no cruise...

Onto VCDS this evening and found the following fault code

1 Fault Found:
00987 - Lamp for Brake Light; Left (M9)
            30-10 - Open or Short to Plus - Intermittent

Cleared it and all back to normal.

Had plenty of brake bulbs blow in the past but never had any DTCs logged before now.
So if you've got a similar issue - it may be you need to change bulb _and_ check for DTCs.

Hope this is helpful to someone.

Cheers

[revdave]

So just to update this issue. Turns out I had a failing clutch switch which had nothing to do with the brake light fault. Cruise control had worked again after changing the bulb and clearing the fault code but that must've been a coincidence.

After a bit of poking around various forums and playing with VCDS, I narrowed it down to the clutch switch.
http://wiki.ross-tech.com/wiki/index.php/Checking_Cruise_Control_using_Measuring_Values gives the method to check it.

I should also note that under hard acceleration the car was surging as if I was doing a slight lift off the pedal and then back on. Checking forums linked this to the faulty clutch switch.

Clutch switch replaced with a Facet 7.1220 and all is now good. Cruise control working well and no more surging.

Again, hope this is helpful.