Signal From Clutch Vacuum Vent Valve Switch, Checking

Signal From Clutch Vacuum Vent Valve Switch, Checking

Vehicles with 121-pin Engine Control Module -ECM-

Recommended special tools and equipment
- VAG1526 multimeter or VAG1715 multimeter
- VAG1594 connector test kit
- Wiring diagram

Test requirements







- The respective fuses of Clutch Vacuum Vent Valve Switch -F36- must be OK.
- Battery voltage must be at least 11.5 volts.
- All electrical consumers like, for example, lights and rear window heating must be switched off.
- Parking brake must be engaged or else daylight driving lights will be switched on.
- If vehicle is equipped with an A/C system, it must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Ignition switched off.

Test sequence
- Remove driver-side storage compartment.
- Disconnect 2-pin connector from Clutch Vacuum Vent Valve Switch -F36-.







- Measure resistance between terminals 1 & 2 of switch.
Specified value:
Clutch pedal not depressed: max. 1.5 Ohm
Clutch pedal depressed: Infinite Ohm

If specified values are not obtained:
- Replace Clutch Vacuum Vent Valve Switch -F36-.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Readiness Code, Generating

If specified values are obtained:







- Connect multimeter between terminal 1 and Ground (GND) for voltage measurement.
Specified value: at least 11.5 V

If specified value is not obtained:
- Check wire between 2-pin connector terminal 1 and central electronics for open circuit according to wiring diagram.
Wire resistance: max: 1.5 Ohm

If specified value is obtained:
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test







- Check wire between test box and 2-pin connector for open circuit according to wiring diagram.
- Terminal 2 & socket 39
Wire resistance: max: 1.5 Ohm
- Also check wires for short circuits to each other, to vehicle Ground (GND) and to B+.
Specified value: Infinite Ohm

If no wiring faults are found and the resistance values are OK:
- Replace Motronic Engine Control Module (ECM) -J220-.