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Camshaft Position Sensor: Testing and Inspection






Diagnostic Procedures



Camshaft Position Sensor, Checking

Use only gold-plated terminals when servicing terminals in harness connector of sensors.

Test Conditions

Special tools, testers and auxiliary items required

Hand multimeter (V.A.G 1526) or Multimeter (V.A.G 1715)

Test adapter kit (V.A.G 1594)

Wiring diagram

Battery voltage (both batteries) must be at least 11.5 Volts.

All electrical consumers such as, lights and rear window defroster must be switched off.

For vehicles with automatic transmission, selector lever must be in " P".

Parking brake must be engaged.

The Ground (GND) connections between engine and body must be OK.

Ignition switched off.

Fuses in right instrument panel fuse holder must be OK:

Right instrument panel fuse holder





Test Sequence

Cylinder bank 1

- Disconnect corresponding 3-pin connector from Camshaft Position sensor:

Camshaft Position (CMP) sensors 1 and 3





1 Camshaft Position (CMP) Sensor 1 (G40) on intake camshaft
4 Camshaft Position (CMP) Sensor 3 (G300) on exhaust camshaft

Cylinder bank 2

- Disconnect corresponding 3-pin connector from Camshaft Position (CMP) sensor:

Camshaft Position (CMP) sensors 2 and 4





1 Camshaft Position (CMP) Sensor 4 (G301) on exhaust camshaft
4 Camshaft Position (CMP) Sensor 2 (G163) on intake camshaft

Cylinder bank 1 and 2

Before disconnecting harness connectors, mark allocation to component.

Cylinder bank 1 with cylinders 1 through 6 is located at right in direction of travel.

Cylinder bank 2 with cylinders 7 through 12 is located at left in direction of travel.

Checking voltage supply

- Connect multimeter to terminal 1 (B+) and 3 (Ground (GND)) of the respective connector for Camshaft Position (CMP) sensor for voltage measurement.





- Switch ignition on. Specification: at least 4.5 V

- Switch ignition off.

If no voltage is present:

- Check wires to Engine Control Module according to wiring diagram.

Checking wires to Engine Control Module

Checking wires to Engine Control Module

Cylinder bank 1

- Connect test box to Engine Control Module (ECM) (J623) wiring harness on connecting test box for wiring test, refer to Repair Manual,

Cylinder bank 2

- Connect test box to Engine Control Module (ECM) 2 (J624) wiring harness on connecting test box for wiring test.

Cylinder bank 1 and 2

- Check wires between test box and 3-pin connector to Engine Control Module for open circuit according to wiring diagram. Wiring resistance: max. 1.5 ohms





Cylinder bank 1









Cylinder bank 2





Cylinder bank 1 and 2

- Check wires for short circuit to each other. Specification: infinite ohms

- Erase DTC memory of Engine Control Module => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09, Diagnostic mode 4: Reset/erase diagnostic data.

- Generate readiness code => [ Readiness Code, Generating ] Monitors, Trips, Drive Cycles and Readiness Codes.

If no malfunction is found in the wires and there was voltage between terminals 1 + 3:

- Replace respective camshaft position sensor.

- Erase DTC memory of Engine Control Module => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Modes 01 - 09, Diagnostic mode 4: Reset/erase diagnostic data.

- Generate readiness code => [ Readiness Code, Generating ] Monitors, Trips, Drive Cycles and Readiness Codes.

If no malfunction is found in the wires and there was no voltage between terminals 1 and 3:

Cylinder bank 1

- Replace Engine Control Module (ECM) (J623).

Cylinder bank 2

- Replace Engine Control Module (ECM) 2 (J624).