With Manufacturer's Scan Tool
Clutch Vacuum Vent Valve Switch, Checking
The Clutch vacuum vent valve switch -F36- informs the control module when the clutch is being engaged or disengaged. This prevents the engine from jolting when disengaging and engaging and also prevents the engine from racing during disengaging operations when the cruise control system is switched on.
Special tools and equipment
- VAG 1551/1552 Scan tool with adapter cable VAG 1551/3
- Test box VAG 1598/22
- Digital multimeter US1119 (Fluke 83 or equivalent)
- Adapter set VAG 1594
- Wiring diagram
Checking conditions
- Fuses 13 and 43 must be OK.
- The battery voltage must be at least 11.5 V.
Test sequence
- Connect VAG 1551/1552 (Connecting scan tool and selecting engine electronics control module). Scan Tool Testing and Procedures
- Run engine at idle speed and press buttons -0- and -1- to select "Engine electronics" address word 01.
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- to select "Read measured value block" function 08 and confirm entry with -Q- button.
Indicated on display
Read measured value block HELP
Input display group number XXX
- Press buttons -0-, -0- and -6- to select "Display group number 6" and confirm entry with -Q- button.
- Observe display in display field 2.
Read measured value block 6 ->
0 km/h 0 0 0 000000 255
- Specification: 0 x x
- Operate clutch pedal. The left-hand position must change to 1.
Read measured value block 6 ->
0 km/h 1 0 0 000000 255
- Specification: 1 x x
- Press the -> button.
- Press buttons -0- and -6- to select "End output" function 06 and confirm entry with -Q- button.
- Switch ignition off.
If the specifications are not obtained:
- Disconnect 2-pin connector from clutch vacuum vent valve switch.
- Measure resistance at switch terminals.
- Specification: Clutch not depressed: max. 10 ohms; Clutch depressed: Infinity ohms
If the specifications are not obtained:
- Replace clutch vacuum vent valve switch.
- Check DTC memory and, if necessary, repair any malfunctions and then erase. Reading Diagnostic Trouble Codes
- Read readiness code. Testing and Inspection
If the DTC memory has been erased or the engine control module was disconnected from permanent battery positive (B +), the readiness code must be generated again. Testing and Inspection
If the specifications are obtained:
- Remove wiper arms and plenum cover.
- Connect test box V.A.G 1598/22 to control unit wiring harness.
- Check wiring between test box and connector for open circuit according to wiring diagram.
Terminal 1 + socket 2
Terminal 1 + socket 28
Terminal 2 + socket 46
- Wire resistance: max. 1.5 ohms
- Additionally check wires for short to one another, to vehicle Ground and to battery positive (B+).
- Specification: Infinity ohms
If wiring and the resistance measurement values are OK:
- Replace engine control module. Service and Repair