LJH

So after 4 years of trouble free service the S4 has given me my first issue. The car is a 10/01 build with a M box stock but I have been running a APR Stage 1 box (T box?)for 25K miles with out so much as a peep that anything was wrong. Today I went to back the S4 out of the garage and at first it did not want to start. Tried again and it fired after a few cranks which was weird as it always starts right up. Did not think much about it till this evening when I went to put it away and she would not fire. Well I pulled out the VAG-COM (first time I have had to use it so I am a total newbie with it so bear with me). Here is what I got.

VCDS Version: Release 805.4
Data version: 20090602

Wednesday,17,June,2009,20:25:00:42841

Chassis Type: 8D - Audi A4 B5
Scan: 01 02 03 08 15 16 17 25 35 37 45 55 56 57 67 75 76 77

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8D0-907-389.lbl
Part No: 8D0 907 389 E
Component: ABS/ESP allrad D56
Coding: 04395
Shop #: WSC 06435

1 Fault Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-00 - -

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8D0-820-043-1D.lbl
Part No: 8D0 820 043 P
Component: A4 KLIMAAUTOMAT D58
Coding: 00160
Shop #: WSC 08259

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8D0-959-655-AI8.lbl
Part No: 8D0 959 655 G
Component: Airbag Front+Kopf 2002
Coding: 00304
Shop #: WSC 40104

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8D0-920-xxx-17.lbl
Part No: 8D0 920 981 B
Component: B5-KOMBIINSTR. VDO D12
Coding: 02264
Shop #: WSC 08259

1 Fault Found:
01314 - Engine Control Module
49-00 - No Communications

-------------------------------------------------------------------------------
Address 35: Centr. Locks Labels: 8D0-862-257.lbl
Part No: 8L0 862 257 N
Component: CV-Pump, Alarm, RC D16
Coding: 16140
Shop #: WSC 06435

1 Fault Found:
01370 - Alarm triggered by Interior Monitoring
35-00 - -

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 4B0-951-173.lbl
Part No: 4B0 951 173
Component: Innenraumueberw. D03
Coding: 00101
Shop #: WSC 06435

No fault code found.

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4B0-907-357-AUT.lbl
Part No: 4B0 907 357
Component: LEUCHTWEITEREGLER D004
Coding: 00012
Shop #: WSC 06435

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8D0-035-1xx-56.lbl
Part No: 8D0 035 195 A
Component: Radio D00
Coding: 00110
Shop #: WSC 06435

No fault code found.

End ---------------------------------------------------------------------


After seeing that I thought I should check the connection with the ECU and even after un-plugging and re-plugging it back in I had no luck. Then I thought I should try the stock ECU that came with the car. Fired right up and no codes.

So my question is: How often do ECU's go bad? I have been driving "chipped" Audi's for almost 20 years now and have never had an issue after 250+K miles.

What would you guys suggest as a plan of action? Send it back to APR to have a look?

Cheers,
Jim

complacentsee

Have you tried to just scan the engine module? Or does it fail vagcom communications?

rktskicar

Try to do an engine controller connection in VCDS. Read the codes and report back. If that does not work, remove your ECU and then put it back in and see if it will connect and/or start. If that does not work, find someone in your area that you can swap in their ECU and check to if works. Make sure to check your fuses as well.

Bruce

LJH

Swapped out to the original ECU and the car is running fine with no codes.

LJH

Will check that tomorrow night and report back.

rktskicar

Then will need to send your T ECU to APR to see what's wrong with it. Is it an EMCS ECU? If so, you can open it up and check out connections on the board to the chips.

Bruce

LJH

Pardon my ignorance but what is a EMCU? My box looks to have Torx fasteners on each corner.

Cheers,
Jim

complacentsee

I believe thats what APR has branded there chip that use the cruise control stalk to change between programs. And that has a large additional board added into the ECU box. If so, it could be a loose connection on that chip/board.

rktskicar

EMCS is APR's Enhanced Modular Chipping System that lets you have more than 1 program in your ECU. Yes those are Torx fasteners on each corner. Just get a Torx and open it up and check it out.

Bruce

LJH

Yuppers, have a ECMU then, stock and 93 octane. I will give them a shout at lunch today and see what they say.

Thanks guys.

Cheers,
Jim