Ignition Coil: Testing and Inspection

NOTE: The ignition coil and the power output stage are integrated into a single component.


Determine the non-working i.e. misfiring cylinder as follows:
- With the engine running, disconnect fuel injector connectors in sequence and observe running of the engine.
or
- Compare spark plugs of all cylinders with each other and look for soot covered electrodes.

Once the cylinder is determined:
- Swap spark plug from misfiring cylinder with one from another cylinder.

If the malfunction travels with the spark plug:
- Replace spark plug.

If the malfunction remains at the cylinder:
- Swap ignition coil of the misfiring cylinder with one from another cylinder.

If the malfunction travels with the spark plug:
- Replace ignition coil.

If the malfunction remains at the cylinder:

Check Ground (GND) connection
- Remove 4 - pin connector from ignition coil.







- Connect voltage tester V.A.G 1527 B as follows:

Harness connector terminal Measure to
2 B+
4 B+

- LED must light.

If LED does not light:
- Check the wire connections.

If LED lights:

Checking voltage supply







- Connect multimeter for voltage measurement as follows:

Harness connector terminal Measure to
1 Engine Ground (GND)

- Turn ignition on.
- Specified value: approx. battery voltage

If specified value is not obtained:
- Check the wire connections.

If the specified value is met:
- Check activation of the power output stage.

Checking activation of the power output stage
- Remove connectors from all four fuel injectors.


NOTE: Fuel must not be injected in order to avoid damage to the catalytic converter. Therefore the connectors must be removed from the fuel injectors.


- Remove 4-pin connector from the ignition coil.
- Connect voltage tester V.A.G 1527 B to terminals 2 and 3 of the connector.
- Operate starter briefly.
- LED must blink (short blink signal)

If specified values are not obtained:
- Connect test box V.A.G 1598/31 on wiring harness to engine control module, the engine control module is not to be connected. Refer to "Wire and Component Test Using VAG 1598/31 Test Box" Testing and Inspection
- Check the following wire connections for short circuit between Ground (GND) and B+:

Harness connector terminal Test box V.A.G 1598/31 socket
3 (cyl. 1) 102
3 (cyl. 2) 95
3 (cyl. 3) 103
3 (cyl. 4) 94

- Repair open circuit or short circuit if necessary.

If no malfunctions are found in wires:
- Replace the combined component ignition coil with power output stage.