How to fix cruise control

[montyrs2]

Morning all.

So I'd like to start to look at the cruise control on my S2. It's all there but doesn't work, or at least I can't get it to work.

I put the slider to on and hold set, take foot of throttle and car just slows down. Unless it gets set a different way I assume it's not working.

Appologies if there are already a million threads on this, but what are the common faults and where is the best place to start de bugging it?

Many thanks

[audicoupe2.3]

The most common failure is the switchboard. I would start from there. It is a common fault of cold welds. Sometimes you can repair visibly, if not with a magnifying glass. Review welds affected. If they are not you can give an overview with a hairdryer carefully. If the unit is fine, it would have to first find out if the problem is electrical or pneumatic. For example if you go hear the relay in the exchange beginning in serious tire. Leaks, switches pedals shabby. both pneumatic and electrically. Provar tucking pump current directly. etc ... There are many tests you perform, with patience can work. Although in these cases from my own experience I am inclined to the first unit.

Luck.

http://www.s2forum.com/forum/showthread.php?t=61777

Thanks to this post to find out the common failure of these exchanges are cold welds. Comprove And it was true. Well I picked up a few and most had the same problem. And I could repair.


http://forums.audiworld.com/a6-s6-c5...-16-a-1728645/

http://tech.bentleypublishers.com/thread.jspa?threadID=25504&start=0&tstart=0

[veneto rs2]

When switch on the Crusie you can here an audible "click" behind the glovebox where its control module it's located.
If you don't here the click then it's quite sure it's an electrical problem could be:

control module faulty as per audicoupe 2.3 post
Stalk contacts as common as the control module solderings
Electrical contacts on the pedals
Faulty vaccum pump (to check if the pump works you need to connect two positives and one negative)

Another thing it's an air leak that prevents the pump to built the necessary vacuum which brings you into a mechanical (air vacuum) issue.

Could be the pipe to the membrane actuator that sucks the throttle
Or the pipe that goes to the pedals valves
Or one of the pedals valves faulty or not sitting in the right (normally close) position
Both easy to check

I found a little leak on the pipe that seerves the pedals by loosing it off form its junction and by putting a screw to close it.
If with this it works then you can concentrate on the pipes and valves.
Do not use the cruise without the air/vacuum connections the system it's been developed to be redundant in safety so that you have two security devices electrical and machanical (air vaccum)

I'm pretty sure I forgot something but for now that's what I remember.....

Stefano

[Vorsprung durch Technik]

Cheers audicoupe2.3 and veneto rs2.Great information you guys have put up.I am sure it will help me if i ever have a problem in the future which is most probably.