Planckscale

First thing first. Though I have never posted before, I have been quietly reading your posts and learn a lot from you guys. I thank you for that.

Now, My problem.
I had serious flooding in the garage that left my car (1998 A6 2.8) full of water. I had to replace the whole interior (front and real leather seats, plus the door panels). Expensive but at least I knew how to do it. The shifter on the other hand, is an issue I haven’t been able to resolve.

I cannot move the shifter from “Park” position, nor can I start the engine on this position. The shifter-lock light (the one that warns you to press the brake pedal before shifting out of park) stayed on even when I stepped on the brake pedal.

After some trials, I was able to move the car by pulling the shifter to neutral position, start the car and then put it into drive. But lately it will not move when shift to "drive" position. It feels like the trany does not engage when in "drive" position. But it still fires up in "neutral" position.

The shift lock light started to flicker for sometime, and then it died out completely. I have recently changed the brake light switch following the advice here on the board, but to no avail. I am also experiencing difficult removing the key from the ignition, though this does not happen often.

From a long search here, I think my next troubleshooting should be the TCU and the shift-lock solenoid. Am away from home, but would return in a week and continue troubleshooting.

Any additional pointers/advices will be highly appreciated.

4Driver4

Did you dry out the TCU after the flood? Checked it with VAG-COM. Time for some basic troubleshooting.

Planckscale

No I did not check the TCU. Honestly, didn't know the TCU existed and has such a major role. I thought most computing were done on the ECU.

So the TCU has been there since the water damage, over 6 months ago!

Here is the VAg output, taken when the engine was off (key on "on" position) so 'am not too concern with the other engine fault at the moment:

-----------------------------------

Address 03: ABS Brakes
Part No: 8E0 614 111 M
Component: ABS/EDS 5.3 QUATTRO D31

1 Fault Found:
01203 - Electrical Connection between ABS and Instrument Cluster
03-10 - No Signal - Intermittent


Address 02: Auto Trans
Part No: 4B0 927 156 G
Component: AG5 01V 2.8l5V USA 8509
Coding: 00000
Shop #: WSC 00000

1 Fault Found:
00526 - Brake Light Switch-F
27-00 - Implausible Signal


Address 01: Engine
Part No: 4D0 907 551 AH
Component: 2.8L V6/5V MOTR AT D01
Coding: 06252
Shop #: WSC 02324

12 Faults Found:
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent
17967 - Throttle Body (J338): Fault in basic settings
P1559 - 35-10 - - - Intermittent
17973 - Throttle Actuator (J338): Lower Stop not Reached
P1565 - 35-10 - - - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent
16690 - Cylinder 6: Misfire Detected
P0306 - 35-10 - - - Intermittent
16689 - Cylinder 5: Misfire Detected
P0305 - 35-10 - - - Intermittent
18014 - Rough Road/Engine Torque Signal from ABS: Electrical Malfunction
P1606 - 35-10 - - - Intermittent
16890 - Idle Control System: RPM Lower than Expected
P0506 - 35-10 - - - Intermittent
18034 - Powertrain Data Bus: Missing Message from TCU
P1626 - 35-00 - -
Readiness: 0110 1101


Address 17: Instruments
Part No: 4B0 919 930 B
Component: C5-KOMBIINSTR. VDO D11
Coding: 07262
Shop #: WSC 00000

1 Fault Found:
00771 - Fuel Level Sensor (G)
30-10 - Open or Short to Plus - Intermittent

4Driver4

I'd check the TCU to make sure it looks OK (open it up and see if it's green inside), clear all the codes, and go from there. You might have a bad brake light switch.

Unrelated, but it looks like your ABS controller has failed.

Planckscale

Thanks for the help.

I did change the brake light switch - followed the basic installation described here on several post. I left about 1/2 millimeter gap as recommended. Do you think I missed something?

The ABS issue started as the infamous blinker (both ABS and Brake light blinking indicating something wrong with the ABS), but it got worse after changing of the seats. I suspect the ABS on the rear seat is not connected properly. I just want to get the car moving for now.

Planckscale

Pulled the TCM out and boy, it was rusted as hell!
Hope eBay will have one soon, though the shipping cost will kill me

Will post.