P0658 U0100 ABS, TC, and brake light on

[razgriz10000]

Did some searching and I only found 1 other thread and didn't really have any helpful info.

Car has been hard to start in the mornings for 3 days now. Today I got 3 lights on the dash (ABS, TC, Brake) and 2 codes P0658 and U0100




Anyone have any ideas before I go shell out cash to a dealership for diagnostics. Any input is appreciated.

[Okedokey]

Check if there is any water in the ECU box. Check all fuses and relays.

[razgriz10000]

I don't have the original owners manual so is the ECU box the one box under the hood, directly in front of the drivers side

[Denio24]

I don't have the original owners manual so is the ECU box the one box under the hood, directly in front of the drivers side

Yes close to the firewall, driver's side.

[never_comment]

Please let me know what the resolution to this problem was. I have the exact same problem. Exact same 2 codes. Exact same lights. Furthermore my car will not start most of the time. I was stranded at work for 3 hours until it magically started. Any help would be appreciated.

[B7S3wannabi]

Start by replacing the main relays under that plenum box where the ECM is.

[never_comment]

To add to this problem, when I put my car in the 'ON' position, I hear the fuel pump in the trunk click, but then I don't here the low hum that indicates it might not be pumping. I am comparing the sound of my car to another one in working order. The car has 160k miles, and I replaced a fuel pump in that other a4 b7 around this mileage. Would the relays that you speak about possibly be the cause? Or should I replace the pump (which is super not fun)?

[B7S3wannabi]

Relays

[never_comment]

Thanks. So do you just buy the replays you think might be a problem at like autozone and replace them to see if it works?

Here are the codes I just pulled as well:

Tuesday,25,July,2017,20:08:53:62939
VCDS -- Windows Based VAG/VAS Emulator
VCDS Version: Release 12.12.0 (x64)
Data version: 20130910


Mileage: Repair Order: A4B725JUL2017

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Address 01: Engine Labels: 06F-907-115-AXX.lbl
Control Module Part Number: 8E0 910 115 P HW: 8E0 907 115 D
Component and/or Version: 2.0l R4/4V TFSI 0020
Software Coding: 0104010A190F0120
Work Shop Code: WSC 07110 444 83906
VCID: 2E53E833B9E29E6E36F-807B
5 Faults Found:

012423 - Voltage Supply Relay for Engine Components
P3087 - 002 - Electrical Malfunction - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 0
Fault Frequency: 2
Reset counter: 255
Mileage: 256352 km
Time Indication: 0

Freeze Frame:
RPM: 246 /min
Load: 68.6 %
Speed: 0.0 km/h
Temperature: 37.0°C
Temperature: 39.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 10.033 V

001672 - ECM Power Relay Load Circuit: (J271)
P0688 - 002 - Open Circuit
Freeze Frame:
Fault Status: 01100010
Fault Priority: 0
Fault Frequency: 3
Reset counter: 255
Mileage: 256393 km
Time Indication: 0

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 84.0°C
Temperature: 77.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 0.000 V

005668 - MIL Request Signal Active (Check TCM for errors too!)
P1624 - 008 -
Freeze Frame:
Fault Status: 01101000
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 256393 km
Time Indication: 0

Freeze Frame:
RPM: 1124 /min
Load: 51.0 %
Speed: 0.0 km/h
Temperature: 38.0°C
Temperature: 37.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 13.335 V

000406 - Engine Oil Temp. Sensor (G8)
P0196 - 004 - Implausible Signal
Freeze Frame:
Fault Status: 01100100
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 256435 km
Time Indication: 0

Freeze Frame:
RPM: 0 /min
Load: 0.0 %
Speed: 0.0 km/h
Temperature: 84.0°C
Temperature: 77.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 0.000 V


Readiness: 0100 0100

[Okedokey]

Relays.

Open the ecu plenum, ensure no water, rust etc. Replace all the relays there while you're at it. They don't have to be Audi ones, just the same package (e.g. construction), voltage and amperage. Take them to an electrical shop (frys in USA?) and replace.

[never_comment]

To Obedokey and B7S3wannabi who kept insisting it was the relays...it was in fact...the relays (or at least one of them). I went ahead and replaced the three (2X 614, 395) here for the heck of it:

https://photos.app.goo.gl/ja4A4XdqjgTD43zy2

I actually measured the resistance across them with them energized with 12V and measured .5-.6 Ohms on both of them. The new relay measured .4 Ohms. I think the relay was more corroded than anything and perhaps not completely bad. I probably could have cleaned off the contacts, but for $14 a piece it was worth replacing them. Here is what the contacts looked like:

https://photos.app.goo.gl/nnGZvtBmARNFJTKp1

https://photos.app.goo.gl/P1SbhZvG8lMiespk1

Thanks to everyone. Diagnosed and fixed in under a day is pretty amazing for me.

The wiper came off by soaking in penetrating oil for 30 minutes then using a prybar gently while tapping the threaded portion with a hammer. That and some back and forth in the window wipe direction by hand every once in a while (probably good for getting the penetrating oil in all of the splines. Not as bad as some people had it, but not easy either.

The relays are the real pain to get out. I could not without cracking the plastic casing.

Thanks again everyone.

[never_comment]

Also this thread deals with the same issue for future peoples reference. I used both for help solving the problem:

http://www.audizine.com/forum/showth...el-pump-relays