Kirk

The following is a document that I prepared to help me keep track of the problem and the testing I've performed. From searching Audiworld and reading robertbently and ross-tech forums, it appears that the most common solution to my symptoms is to replace the ABS module.

Anyone have any other suggestons or do I indeed have a failed ABS module?

Thanks,
Kirk

here are my notes:

ABS fault trouble shooting

Vehicle info:
2000 Audi A4 1.8TQM. ATW motor
Car has ABS, EDL, EBD but no ASR or ESP
Engine ECU part number: 4B0 906 018 P
ABS module part number: 8E0 614 111 A
Instrument cluster part number: 8D0 920 930 DX

Symptom:
ABS light and flashing brake light came on in the instrument cluster. The instrument cluster warning lights went away and then appeared again and went away. This process occurs at random and the duration varies. While warning lights are on, braking performance is diminished as EBD is disabled and there is no ABS. With codes stored in the engine ECU, engine performance seems diminished (limp mode).

Checked brake fluid level and it looked a bit low so topped up level.

Checked ECU for fault codes and the following fault code was present:
18014 - Rough Road/Engine Torque Signal from ABS: Electrical Malfunction
P1606 - 35-10 - - - Intermittent

Checked ABS for fault codes and the following fault code was present:
01203 - Electrical Connection between ABS and Instrument Cluster
03-10 - No Signal - Intermittent

Cleared code from ABS module and the code went away. Cleared code from ECU and the code went away. Then performed with the throttle body alignment, and reset the readiness code. Went for a test drive and the codes came back.

While the instrument cluster warning lights are on, cannot connect with the VAG tool to the ABS control module or the instrument cluster. And without removing the code from the ABS control module the fault code in the ECU is permanent and if cleared, reappears.

Disconnected the ABS wire harness from the ABS control module. No change to the instrument cluster warning lights. Can now connect to the instrument cluster with the VAG tool. Reconnect the ABS wire harness to the ABS control module and communication between the VAG tool and the instrument cluster is lost.

Disconnected the ABS wire harness from the ABS control module. Disconnected the Engine ECU wire harness from the ECU. Disconnected the three instrument cluster connectors (green, blue, grey) from the instrument cluster. Performed continuity checks for the following wires:
ABS pin 1 to ABS pin 2 (right rear abs sensor): 1700 ohms
ABS pin 4 to ABS pin 5 (right front abs sensor): 1200 ohms
ABS pin 6 to ABS pin 7 (left front abs sensor): 1200 ohms
ABS pin 8 to ABS pin 9 (left rear abs sensor): 1700 ohms
ABS pin 16 to ABS pin 19: ground checks ok
ABS pin 16 to ABS pin 15 (abs controller power): 12.08V
ABS pin 16 to ABS pin 17 (battery positive): 12.09V
ABS pin 16 to ABS pin 18 (battery positive): 12.09V
ABS pin 10 to Inst cluster green connector pin 11 (standing time): 0 ohms
ABS pin 11: k-wire could not test
ABS pin 13 to Engine ECU connector pin 74 (MAD signal): 0 ohms
ABS pin 14 to brake light switch: checks ok
ABS pin 21 to Inst cluster green connector pin 21 (ABS warning light): 0 ohms.
ABS pin 23 to Nav system: did not check
ABS pin 24 to Nav system: did not check
All other ABS pins are not connected.

Connected the three control modules back up. Cleared all codes, reset the engine readiness codes and went for a test drive. ABS and flashing brake warning lights came back.

Disconnected the ABS wire harness from the ABS control module and measured the following signals from the ABS wire harness with the car running:
Gnd to pin 21 (ABS warning light): 10.9V
Gnd to pin 13 (MAD signal): 11.5V
Gnd to pin 11 (k-wire): 11.9V
Gnd to pin 10 (standing time): 12.8V
Gnd to pin 14 (brake light switch): 200mV
Gdn to pin 15 (ABS controller power): 13.65V
Gnd to pin 17 (battery positive): 13.65V
Gnd to pin 18 (battery positive): 13.65V

Performed the follow resistance checks on the ABS controller pins:
Pin 16 to pin 21 (ABS warning light): open circuit
Pin 16 to pin 13 (MAD signal): open circuit
Pin 16 to pin 11 (k-wire): 112k ohms
Pin 16 to pin 10 (standing time): 5k ohms
Pin 16 to pin 19 (ABS pump ground to ABS controller ground): 23k ohms

Reconnected the ABS wire harness to the ABS control module. No change to warning lights in instrument cluster.

With fault codes still present. Swapped engine ECUs with a spare one. Cleared Engine ECU fault codes, performed throttle body alignment and reset readiness codes and went for a test drive. ABS and flashing brake warning lights came back.

Ordered replacement ABS module, part number: 8E0 614 111 E. The part original part, ending in A has been superseded by the E.

flying_low

AoA will pay for most of the replacement cost even if out of warranty. My 2000 S4 is at the dealer right now getting it replaced.

Kirk

... my car is going to the dealer tomorrow for the pump to be replaced. I'll see what AoA can do to help.

Kirk

QCRAZY

<a href="http://www-odi.nhtsa.dot.gov/ivoq/">NHTSA</a>

Also, make sure you contact AoA about replacing it for you....
<A href="http://www.audiusa.com/customer_care_feedback/">AoA</a>

2000a4audi

i had same 3 months ago was my abs computer i bought used cause new is $1500 from local audi dealer

Kirk

... they diagnosed it as a faild module so they replaced it. It took them an extra day to sort it out but in the mean time I had a service loaner.

The part cost $1500 plus the labour to install it. I'm out of pocket for this right now but have a call into AoA to see if they'll help with the tab.

Thanks to everyone for the input.

Kirk

JohnM99A4

Hi Kirk. I have the same problem as you. The dealer offered to replace mine for $1k (I've spent $6,600 with them in the last 2 months!). I called AoA and they said they wouldn't kick in anything towards the repair. They said my car had too many miles (72k on a 1999 1.8T).
So I just filed a complaint with NHTSA (
www-odi.nhtsa.dot.gov odi #10078914). Maybe if enough of us do this Audi will have to make a recall or take some sort of action on this one.
Good luck to you.

allevil004

I know some of us have experienced this. My module is bad according to the dealer, only they get no reading when hooked up to the computer. The problem is at low speeds. I can make a complete stop from about 40-30mph and have no problem however once I let off the brake and re-apply at about 20mph and below, my brake pedal goes nuts and kicks back at me. Very frustrating. Audi says I was too far out of warranty and will do nothing. This happened only after I had a complete brake replacement at the dealer (pads, rotors). Any ideas?

Felix

sidespar

I stumbled upon this old thread after Audiworld changed to the VB forum software. I just wanted to post for anybody else who also finds this thread, that you do not need to put in a new module - it is a waste of money. It is a lot cheaper and more effective to have your current abs control module rebuilt.

I developed a reliable method of repair about a year ago, and the ~200 or so modules I have repaired since then have experienced zero failures. I charge a small fee for the rebuild and can rebuild one in about 2-3 hours. Anybody who needs more info about this problem or is interested in a rebuild, feel free to send me an email: sidespar@yahoo.com

freude09

I stumbled upon this thread thinking that was a new post, but I just want to tell that I had the same problem in my Audi... and for me instead of rebuilding the abs control module, I just bought a new one instead... it's much cheaper anyway!
__________________
Love is like racing across the frozen tundra on a snowmobile which flips over, trapping you underneath. At night, the ice-weasels come. | Hot rocker arm studs here