Accelerator Pedal Position Sensor: Testing and Inspection

Accelerator Pedal Position Sender, Checking

Special tools, workshop equipment, test and measuring appliances and aux. items required







- V.A.G1526 A Hand multimeter
- V.A.G1594 A Adapter set
- V.A.G 1598/31 Test box
- VAG 1551 scan tool or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3
- Wiring diagram

Function
Both accelerator pedal position senders -G79 and -G185 on the accelerator pedal pass the driver's requirements on to the engine control module independently of one another. Both senders are installed together in a housing.

Check conditions







- The fuses must be OK.
- The battery voltage must be at least 11.5 V.

Test sequence
- Connect VAG 1551 scan tool ((V.A.G 1552) and with ignition switched on select engine electronics control module with the "Address word" 01:

Indicated on display:


Rapid data transfer HELP
Select function XX


- Press keys 0 and 8 for the function "Read measured value block" and confirm entry with Q key.

Indicated on display:


Read measured value block
Input display group number XXX


- Press keys 0, 6 and 2 for the "Display group number 62" and confirm entry with Q key.

Indicated on display: (1 to 4 = Display zones)


Read measured value block 62 ->
1 2 3 4


- Check specification of sender 1 (G79) at idling stop in display zone 3.
Specification: 6 to 96 %
- Check specification of sender 2 (G185) at idling stop in display zone 4.
Specification: 3 to 48 %


NOTE: The engine control module calculates the voltage values of the angle sender in percent relative to 5 Volt and displays these as a percentage figure (5 Volt supply voltage equates to 100%).


- Operate the accelerator pedal slowly until fully depressed and observe the angle sender figures in display zones 3 and 4:
The percent figures in display zone 3 must rise evenly. The tolerance range of 6 to 96 % is not covered completely.
The percent figures in display zone 4 must rise evenly. The tolerance range of 3 to 48 % is not covered completely.


NOTE: The figure displayed in display zone 3 must always be approximately double that displayed in display zone 4.


- Press the -> key.
- Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
- Switch off ignition.

If the display does not indicate as described:
- Check accelerator pedal position sender voltage supply and wiring connections.