With Manufacturer's Scan Tool

Ignition Coils With Power Output Stages, Testing

Special tools and equipment






- VAG 1526A
- VAG 1527 B
- VAG 1594A
- VAG 1598/31

Test sequence

NOTE: Each ignition coil is combined with its power output stage as a single component.






- Remove engine cover panel -1--arrows-.

The procedure for identifying an inoperative or misfiring cylinder is as follows:
- Test misfiring recognition. Misfire Recognition, Checking

If misfiring is detected:
- Continue test on cylinder indicated => "When the defective cylinder has been identified:".

If no misfiring is detected:
- Unplug the connectors from the injectors in turn with the engine running, and observe how the engine runs.

or

- Compare the spark plugs of all cylinders with each other and check for soot on the electrodes.

When the defective cylinder has been identified:
- Swap spark plug of defective cylinder with one from another cylinder.

If the fault moves with the spark plug:
- Replace spark plug.

If the fault remains in the same cylinder:
- Swap ignition coil of defective cylinder with one from another cylinder.

If the fault moves with the ignition coil:
- Replace ignition coil.

Testing Ground connections






- Unplug 4-pin connector -1 - from ignition coil -2-.






- Connect VAG 1527 B voltage tester as follows:

Connector Measure against
Contact
2 Battery positive
4 Battery positive

- The LED should light up.

If the LED does not light up:
- Check the wiring.

If the LED lights up:
- Check voltage supply.

Checking voltage supply

Test requirement:
- Fuses for engine electronics OK.






- Connect multimeter (voltage measurement range) as follows:

Connector Measure against
Contact
1 Engine Ground

- Switch on ignition.
- Specification: approx. battery voltage

If the specification is obtained:
- Test activation of power output stages

If the specification is not obtained:






- Unplug current supply relay -1 - (located under cover on left side of bulkhead).

NOTE: To remove protective cover on vehicles with suspension turret stiffener strut; disengage and move down relay carrier on bulkhead. If necessary, also unplug connector on air mass meter

- Carry out the following tests (marked with dots):






- Check wiring between contact 2 of relay carrier (located under cover on left side of bulkhead) and contact 1 of ignition coil connector.
- Test Motronic current supply relay -J271-. With Manufacturer's Scan Tool

If the specification is obtained:
- Test activation

Testing activation of power output stages
- Unplug connectors from all injectors.

NOTE: It is important to ensure that no fuel is injected during the test as this would damage the catalytic converter The connectors on the injectors must therefore be unplugged.






- Unplug 4-pin connector -1 - from ignition coil -2-.






- Connect VAG 1527 B voltage tester to contacts 2 and 3 of the connector.
- Operate starter briefly.
- The LED should flash briefly.

If the specifications are not obtained:
- Connect test box VAG 1598/31 to wiring harness for engine control module. Do not connect to the engine control module itself. Wiring and Component Testing Using VAG1598/31 Test Box






- Test for open circuit and short to positive or Ground in the following wiring connections:

Connector Test box VAG 1598/31
Contact Socket
3 (cylinder 1) 102
3 (cylinder 2) 95
3 (cylinder 3) 103
3 (cylinder 4) 94

- Correct any open/short circuit as necessary.

If no malfunction is detected:
- Replace ignition coil with power output stage (combined as a single component).