vcds errors

[gonny]

Hello
I scanned my car and found some errors as following:

Address 01: Engine (J623-CAGA)     
4698 - Function Restriction due to Faults in Other Modules 
4667 - Accelerator Position Sensors (G79) / (G185) 
          P2138 00 [167] - Implausible Correlation

Address 53: Parking Brake (J540)  
1 Fault Found:
01314 - Engine Control Module

My car is audi a4 b8 (2008) 2.0 tdi

I replace ECM and for some hours error gone but came back.
I replace the accelator pedal but same story, error gone for a while but come back

Any idea?

[Smac770]

Complete scan log is always preferred.

All that is there in that snippet is the P2138 regarding the accelerator pedal position sensor signals as seen at the ECM.

Have you done anything to validate the wiring between the 6-pin plug on the accelerator pedal and the 94-pin plug on the ECM? The wires have to pass through the red 17-pin connector at the base of the driver's side a-pillar, and then through the white 17-pin connector in the ECM box.

Have you tested anything? Do you measure 5V from pin 1 to pin 5, and from pin 2 to pin 3? For each pair, one pin is 5V, one pin is ground; unclear which is which (believe 1 and 2 are the 5V pins, but might be 5 and 2), you should be able to tell with the meter. Pin 4 is the signal pin for the 2/3 pair. Pin 6 is the signal pin for the 1/5 pair.

The potentiometer (the pedal) should vary the signal pin between the ends of 5V and 0V depending on position. Additionally, the 1/5/6 sensor (the G185) has a resistor that reduces the voltage to the potentiometer, so the pin 6 voltage should be less than the pin 4 voltage at all times. This is laid out in SSP 210 on pages 14 and 15; can be found via google searching.