Camshaft Position Sensors, Checking

The following procedure is used to diagnose both Camshaft Position (CMP) Sensor -G40- and Camshaft Position (CMP) Sensor 2 -G163-

Special tools and workshop equipment required 

• Multimeter.
• Wiring diagram.

Test requirements

• The Motronic Engine Control Module (ECM) - J220- fuses OK.
  Fig 1: Identifying Fuses On E-Box In Engine Compartment, Left Side

  Courtesy of AUDI OF AMERICA, LLC
• Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• Vehicles with automatic transmission, shift selector lever into position "P" or "N".
• A/C switched off.
• Ground (GND) connections between engine/transmission/chassis OK.
• Ignition switched off.

Test procedure

-- Perform a preliminary check to verify the customers complaint. Refer to GENERAL DIAGNOSIS .

Start diagnosis

-- Remove the engine cover with air filter.

-- Disconnect the Camshaft Position (CMP) Sensor -G40- electrical harness connector -1- or Camshaft Position (CMP) Sensor 2 -G163-.

-- Switch the ignition on.

-- Using a Multimeter, Check the Camshaft Position (CMP) Sensor -G40- or Camshaft Position (CMP) Sensor 2 -G163- electrical harness connector terminals 1 to 3 for voltage.

Specified value: about 5.0 V

-- Switch the ignition off.

If the specification was not obtained:

Checking wiring

If the manufacturers test box is being used. Perform the following step.

-- Install the test box. Refer to Repair information.

If the manufacturers test box is not being used. Perform the following step.

-- Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE, REPLACING .

-- Using a Multimeter, Check the Camshaft Position (CMP) Sensor -G40- or Camshaft Position (CMP) Sensor 2 -G163- electrical harness connector to the Motronic Engine Control Module (ECM) electrical harness connector T121 for an open circuit.

Camshaft Position (CMP) Sensor 2 -G163- electrical harness connector terminals	Motronic Engine Control Module (ECM) electrical harness connector T121 terminals or test box sockets
1	98
2	87
3	108

Camshaft Position (CMP) Sensor -G40- electrical harness connector terminals	Motronic Engine Control Module (ECM) electrical harness connector T121 terminals or test box sockets
1	98
2	86
3	108

Specified value: 1.5 Ω Max.

If the specified value was not obtained:

-- Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).

-- Check the wiring connection for damage, corrosion, lose or broken terminals.

-- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring and voltage supply was OK:

-- Replace the Camshaft Position (CMP) Sensor -G40- or Camshaft Position (CMP) Sensor 2 -G163-.

If no malfunction is found in the wiring and voltage supply was not OK:

-- Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE, REPLACING .

-- Install the engine cover with air filter.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .

-- End of diagnosis.