Camshaft Position Sensor: Testing and Inspection

CHECKING BATTERY POSITIVE VOLTAGE (B+) SUPPLY
- Connect VAG 1598 test box and VAG 1598/11 adapter harness to the Engine Control Module (ECM) and wiring harness. Refer to VAG 1598 Pin Out Box Connecting. Connecting VAG 1598/31 Test Box
- Connect multimeter (Fluke 83 or equivalent) between test box socket 7 (positive) and Ground (GND).
- Switch ignition ON.
^ Specified value: minimum 9 volts
- Connect multimeter to socket 45 (GND) and socket 7 (positive).
^ Specified value: minimum 9 volts

If one of the specified values is not obtained:
- Connect VAG 1598 test box and VAG 1598/11 adapter harness to engine wiring harness only.
- Check wiring between Camshaft Position (CMP) sensor and ECM for continuity and/or short circuit according to wiring diagram.
- Check for continuity of GND wire from CMP sensor connector terminal 3 to GND.
^ Specified value: maximum 1.0 ohm
- Check positive wire from terminal 1 of CMP sensor connector to test box socket 7 for continuity.
^ Specified value: maximum 1.0 ohm
- Check both wires for short to each othen

If one specified value is not obtained:
- Repair break in wiring and/or short between CMP sensor connector and ECM connector C-.

CMP sensor ECM connector C
connector terminal terminal
1 (B+) 7
2 (GND) GND

If there is neither break in wiring nor short circuit:
- Replace ECM .

CHECKING FUNCTION
NOTE:
To test CMP sensor function, disconnect the 4-pin harness connector from the ignition coil power output stage, then check DTC memory.

- Check voltage supply to CMP sensor.
- Connect VAG 1598 test box and VAG 1598/11 adapter harness to ECM wiring harness. Connecting VAG 1598/31 Test Box
- Connect VAG 1527 voltage tester between test box sockets 8 (CMP sensor signal) and 46 (positive).
- Operate starter a few seconds.
^ LED tester must blink briefly (every 2nd engine revolution).

If the LED tester does not blink:
- Switch ignition off and disconnect 3-pin connector on CMP sensor.
- Check signal wire for continuity from CMP sensor connector terminal 2 and test box socket 8.
^ Specified value: maximum 1.0 ohm

If the specified value is not obtained:
- Repair short and/or open circuit in wiring between CMP sensor connector and ECM connector C.

CMP sensor ECM connector C
connector terminal terminal
2 (signal) 8

If there is no open or short circuit in wiring:
- Connect multimeter (Fluke 83 or equivalent) between test box socket 8 and Ground.
- Switch ignition ON.
^ Specified value: 4.0 volts minimum

If specified value NOT obtained:
^ Replace ECM.

If specified value is obtained:
^ Replace CMP sensor.