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PLC Schematics: Documents & Information

 
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Marko
Blaumann
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Post18-05-2003, 10:18    Subject: PLC Schematics: Documents & Information Quote

Hi!

Does anyone have circuit diagrams for the A6 2.5 TDI C4 AAT engine control unit?
I suspect that the injection start control system is no longer functioning correctly due to a problem with the engine control unit (ECU).
Unfortunately, when the ESP was reinstalled, the cable coming from the fuel injection start valve rubbed against the back of the ESP wheel, causing both cables to short circuit.
Since then, the preheating indicator light has occasionally been flashing, and at speeds of 140, 160, and 180 km/h, there's a kind of braking effect, preventing it from exceeding 180 km/h.
Two errors were detected during the reading process.

Brake pedal monitoring, implausible signal.

2. Injection start control: Difference between setpoint and actual value, intermittent error.

1: According to VAG, the two brake light switches are monitored by the control unit, which means that the amount of ESP (Electronic Stability Program) can be reduced, and this type of "deceleration" can occur, which I do not doubt.
I checked both brake light switches; one had contact issues, while the other was fine.
Despite everything, the error still appears, even after it has been deleted.

Regarding 2: As I already mentioned, the cables were connected.

Now, a question on the sidelines: Could it be that, through this agreement, STG was authorized for termination icon_biggrin.gif?

Hi: Marko
Lieber TDI statt lahme Ente!
-A6 4B2 2.5 TDI AYM-


Translated on 06-10-2026, 21:40.
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diesel.gustav
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Post18-05-2003, 11:18    Subject: PLC Schematics: Documents & Information Quote

Deleted upon request.


Translated on 06-10-2026, 21:42.
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Marko
Blaumann
Blaumann


Joined: 04/15/2002
Posts: 136
Karma: +1 / -0   Thank you, like it!
Location: Rennersdorf

Free account, no CAN development support

Post18-05-2003, 12:04    Subject: PLC Schematics: Documents & Information Quote

Hi Gustav!

I think I've found the cause.
Again, there was contact between a cable and the valve for injection start, but in a location that I couldn't see.
Thank you for the answer!
That's how it should be! There are many possible causes, which allows for a process of elimination.


cu: Marko
Lieber TDI statt lahme Ente!
-A6 4B2 2.5 TDI AYM-


Translated on 06-10-2026, 21:42.
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