Clutch Switch: Testing and Inspection
Clutch vacuum vent valve switch -F36-, checking
This signal is designed to prevent speed overshoots and jerkiness on switching from throttle open to throttle closed and vice versa when disengaging the clutch. It is needed for the cruise control system.
- Connect vehicle diagnostic, testing and information system VAS 5051 or V.A.G 1551 Scan Tool and select engine electronics control unit with "Address word" 01. For this purpose, ignition must be switched on.
Indicated on display
Rapid data transfer HELP
Select function XX
- Press keys 0 and 8 for function "Read measured value block" and confirm entry with Q key.
Indicated on display
Read measured value block 08
Enter display group number XXX
- Press keys 0, 6 and 6 for "display group number 66" and confirm entry with Q key.
Indicated on display
Read measured value block 66 ->
1 2 3 4
Display Group 66:
- Observe readout in display zone 2.
- Depress clutch pedal
Meaning of 4 digit readout of display zone 2:
Display Group 66:
- Allow clutch pedal to return slowly to its normal position.
Display should change from 1 back to 0.
If display does not change:
- Check power supply.
Checking power supply
- Remove driver's storage compartment/trim.
- Disconnect 2-pin connector from clutch pedal.
- Switch ignition on.
- Connect hand-held multimeter (voltage range) between following sockets on connector:
2-pin connector on
wiring harness, socket Specified value
2 + Ground Battery voltage
If specified value is attained:
- Check wiring.
If specified value is not attained:
- Check wiring connections from socket 2 of connector for open circuit/short to Ground.
Checking wiring
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Check following wiring connections for open circuit and short to positive or Ground.
2-pin connector on
wiring harness, socket Test box VAG 1598/31, socket
1 39
Wire resistance: max. 1.5 Ohm
- Correct any open/short circuit as necessary.
If no open circuit is detected:
- Replace clutch vacuum vent valve switch.