summitradio

So the first thing I wanted to do is see what has already been done to screw up this car. It came through a few hands until I got the car. Its in pretty good shape for its age.

First thing I found was a new compressor. I removed and bench checked to see if it maintained pressure and it was fine.

I needed to get out my 30 amp power supply to get it to fire. checked the solenoid and it was ok.

I reassembled and reinstalled it into the car and then my focus was to check the relay and fuse.

I removed the driver knee-panel and pulled the relay/ I pulled the cover and it looked new and the contacts were perfect. Checked it with the power supply and it was ok.

Checked the fuse and it was fine. I then reinstalled everything and reassembled the panels. Time to check the logic!

Got out the vag com and auto scanned . MANY MANY codes. saved it. The battery was changed so there were lo voltage codes everywhere.

Purged them and re-ran the scan. got this from level control. At least I can communicate with the system....


Saturday,23,March,2019,13:00:59:41598
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 18.9.1.0 (x64) HEX-NET CB: 0.4437.4
Data version: 20190114 DS296.0
Ross-Tech: Home

Dealer/Shop Name: 01234



Address 34: Level Control Labels: 4E0-910-553.CLB
Control Module Part Number: 4E0 910 553 K HW: 4E0 907 553 H
Component and/or Version: LUFTFDR.-CDC H07 4590
Software Coding: 0015510
Work Shop Code: WSC 09108 444 59355
VCID: 2B16C6E58AA74E1258-807E
2 Faults Found:

00774 - Level Control System Sensor; Rear Left (G76)
012 - Electrical Fault in Circuit
Freeze Frame:
Fault Status: 11101100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 88
Mileage: 257765 km
Time Indication: 0
Date: 2018.10.20
Time: 12:53:56

00775 - Level Control System Sensor; Rear Right (G77)
012 - Electrical Fault in Circuit
Freeze Frame:
Fault Status: 11101100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 88
Mileage: 257765 km
Time Indication: 0
Date: 2018.10.20
Time: 12:53:56

Well, let's go look at the sensors..... Both of them DISCONNECTED ok why?

nothing else seemed messed with. Took a look at the passenger one Had a case of the green crusties. Corrosion was pretty bad but the connector on the sensor looked fine upon removal.

Gave it a quick clean with De-oxit and set it aside for now. Got out my safety wire and cut some lengths to back pin the connectors and lets do some voltage checks....

Brown = Ground and the blue-white and blue-yellow were 4.6V these are average voltages as this is a PWM signal. I really dont want to drag my scope down there. At least I have some life at the connector.

I tried to clean up and replug the connector but it will not go in. I believe the actual connector is damaged or so full of mud dirt that it wont let the pin seat completely.

So now I think I need to source a new set of connectors. I didn't check the other one yet but I think it may be similar.

I may de-pin and see if I can fix the connector It's under the car so I may just cut it off and work with it on the bench and then solder and shrink wrap it again when finished.

Now to get some lunch and back at it.....

ltooz_a6_a8_q7

I would just plug everything back as original and let the Audi control system to work... Trust the system and not your DVM.
Cheers,
Louis

Jack88

Sounds like you are on the right track. The car doesn't like missing a signal from a sensor! There may be other issues, but one thing at a time.

summitradio

Thanks, guys for the encouragement. I had some jumper wires lying around from my electronics projects and wired up the passenger side. Bingo! I have the pump running now.
it seems the right side runs the pump and the left runs the adaptive headlights. The left is now plugged in but I have a code for a bad sensor. The front has a leak... no real movement.
The back holds air now tho...Small victories.

ltooz_a6_a8_q7

You may have a great deal on the car after all, since the owner was scared of the suspension failure.

summitradio

Yes it was a great deal. Nothing scares me except transmissions... scary!

Found on ebay... connector rebuild kit for Range Rovers. same pinout and sensors.

Came with wires attached. Just solder in ( i never use those crimps) and shrink wrap.

The original harness has a rubber cover that is very tough.

ltooz_a6_a8_q7

Pictures of the connectors?

summitradio

Connectors on ebay....

a little tough to see but they look the same. Im pretty sure they use the same sensors

https://www.ebay.com/itm/YMQ503220-R...97.m4902.l9144

Found my air leak.... bottom of right front airbag blew over the o-ring lands... no wonder the front wouldn't move!

ltooz_a6_a8_q7

For some reasons it's always the right one LOL, may be all Audi passengers are heavier than drivers

summitradio

The only thing I have to go by are the passenger seat presets....


Seriously I think it's just the ditch side of the road that kills them. I have to do upper control arms too....