My S2 coupe bit of a rebuild and repair thread.

[B5NUT]

Thanks guy's. I did wonder if it could be a switch/sensor issue. I've put the door back together but it's easy enough to take apart.

If the microswitch has failed does anyone know if it's possible to repair them?

[Bowie69]

Yep, door lock actuator maladjustment, or microswitch failure. Sometimes the rod doesn't go far enough one way or the other to trigger the switch.

You can get them going again for a while, but better just to replace in my experience.

[newsh]

I don’t think it will be the little microswitch in the lock, this plugs in near the door lock with a 3 pin plug and can be tested with a multimeter from there. Middle pin is common and the other two are momentary. (I’ve changed two of these over the years, is it a PITA to do? Would I like to do another one?) This is the switch that detects you turning the key so it would seem it’s working.
I think the switch that reports the position of the actuator is part of the actuator in the bottom of the door. If it doesn’t report the door is locked the pump runs on till it times out.
It’s been a while since I looked in there but I’ve probably fixed most of these issues on one or other of the cars I’ve had, especially the coupe as it’s done over 300k now..

[steve briance]

Im watching with interest how you fix (there is no dount you will!) your central locking fault as i have exactly the same issue but not enough time to get it sorted. When it occurred, i did find mention that there is a microswitch in the drivers door locking mechanism which fails and, when it does; the system doesnt detect that it is locked and keeps going. Its either the switch or the plastic which presses on it thats snapped off. Maybe worth having a look in there if you currently have it apart to check actuators.

[B5NUT]

So with possible fix for the bomb warning light coming on. I want to solve the final fault on the car! When I say final, I mean the only known fault on the car at this point in time

The last fault is with the central locking. When the car is unlocked the pump runs on for about 10-15 seconds. So far I have removed and checked the drivers door actuator, boot actuator and the fuel cover actuator non of them appear to have a leak.

I'm assuming the pump creates a pressure to unlock the car and a vacuum to lock the car. I don't have any issues with locking or unlocking the car and I get a beep when the car locks. Could this be a sensor issue with one of the locks or the pump it's self? Or do I just have a leak somewhere?

[B5NUT]

Pretty sure I have a spare here if you want to swap it out

Thanks for the offer Dave, I've just placed an order with tradition for a new brake reservoir, booster pressure sensor and PAS reservoir cap. I unplugged the connector going to the brake reservoir and so far no more errors. So I think we could have a winner however I will change all the sensors one by one over the course of a few weeks to make sure I know which one was the faulty sensor.

According to Etka, and to be fair on our cars it's not 100% accurate there is only a replacement sensor for the LHD tank. As I say not 100% sure if that is accurate or not.
sensor.jpg

[Tractor Dave]

Pretty sure I have a spare here if you want to swap it out

[Bowie69]

Yes, knew there was s third switch!

[johne]

Early in my car's life I had similar problems which I traced to the brake fluid level sensor switch in the side of the brake fluid reservoir.

Unplugged the connector and the problem went away. You can tuck the loose plug end up behind the reservoir so it won't be spotted in the MOT

Try it, there's nothing to loose. A new reservoir and switch is expensive for a RHD if it's even still available but the level switch is common across several Audi/VWs of that period and I believe you can change just the switch out. It's one job I've meant to do but 22 years later I'm still running with it unplugged............

[Tractor Dave]

Nothing on the bomb. It's probably the one on the brake booster.

https://audi.7zap.com/en/rdw/audi+co.../6/612-612030/

[Bowie69]

There's a pressure sensor on the master cylinder/booster, plus a switch in the lid of the hydraulic fluid reservoir.

There may be one on the bomb as well, though I don't remember .

[B5NUT]

Turns out this is now the last fix that I will do to my car before the MOT

Replace the brake switch. Don't think there is anything wrong with the switch just the plastic thread has been damaged so think it's slipping over time in the housing. So new one was was fitted today.
switch.jpg


Still getting the occasional brake bomb warning light come up for a second then goes away. It only comes on about 30 seconds after I drive the car away (then immediately goes out) for the first time that day. It then never happens again for the rest of the day. Has to be a sensor but which ones can bring on the Bomb warning light?

Also don't get it if I leave the car to idle, even for 5 minutes. However as soon as I start to drive the car even after being idle the warning light comes on 30 seconds or so later, but then the warning light goes straight out.. Would be nice if the S2 cluster had diagnostics

[psiconauta911]

Did one more job today. Removed the oil splash guard. It had already cracked in two places so I'm glad it's been removed.
1-guard.jpg

Next time the valve cover comes of that part will be taken out to.

Back to my AC problem, you were right B5NUT, the condenser is the culprit, they are hard to find and I found some from Valeo in Germany for around 200€, what do you guys think, have mine repaird (if doable) or buy the Valeo one and replace?

[Tractor Dave]

Yikes
I had better put that on my jobs list.

[B5NUT]

Did one more job today. Removed the oil splash guard. It had already cracked in two places so I'm glad it's been removed.
1-guard.jpg