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With Manufacturer's Scan Tool



Camshaft Position (CMP) Sensor -G40-, Checking

Special tools and equipment
- Test box VAG 1598/31
- Multimeter Fluke 83 or equivalent
- Adapter set VAG 1594
- Wiring diagram

Test conditions
- Sensor malfunction is recognized by On Board Diagnostic

Test sequence






- Disconnect 3-pin connector off Camshaft Position (CMP) sensor -G40- (arrow).






- Connect multimeter using aux. cables from VAG 1594 to measure voltage at contacts 1 (positive) and 3 (Ground) of Camshaft Position (CMP) sensor connector.

- Switch on ignition.
Specification: 4.0 to 6.0 V

- Switch off ignition.

If no voltage is present:
- Remove wiper arms and cowl panel.






- Connect test box VAG 1598/31 to control module wiring harness. Engine control module remains disconnected.






- Check wiring for open circuit between test box and 3-pin connector using wiring diagram:
Contact 1 and test box socket 98
Contact 2 and test box socket 86
Contact 3 and test box socket 108
Wire resistance: max. 1.5 Ohms

- Additionally check wires for short to one another.
Specification: Infinity Ohms

If no wiring fault is detected and voltage was present between contacts 1+3:
- Replace Camshaft Position (CMP) sensor -G40-, item 15.

If no wiring fault is detected and no voltage was present between contacts 1+3:
- Replace engine control module.