Audi Workshop Service and Repair Manuals

Special tools, testers and workshop equipment required

• ◆ V.A.G 1526 A
• ◆ V.A.G 1527 B
• ◆ V.A.G 1594 A
• ◆ V.A.G 1598/31

Installation position => Overview installation positions - Page 24-5

Notes:

• ◆ Ignition coils and output stage form a joint component.
• ◆ Primary resistance of ignition coils cannot be measured.
• ◆ Secondary resistance should be measured first with ignition cables connected to ignition coils by way of spark plug connectors of respective cylinders (interference suppression resistances of ignition cables are also measured in the course of this).

• ‒ Unplug 5-pin connector from ignition coils.

Checking ignition coils -N, -N128, and -N158

• ‒ Disconnect ignition cables from ignition coils.

• ‒ → Connect up multimeter between the two spark plug connectors of the ignition circuit to be checked to measure resistance.
• ‒ Specified value: 16 ... 27 k ω
• ‒ If the specified values are not attained, pull ignition cables off ignition coils and measure ignition cables/ignition coils separately.

• ‒ → To measure resistance, connect up multimeter between the two ignition cable connections of the ignition coil that is to be checked.
• ‒ To measure resistance, connect up multimeter between the two ignition cable connections of the ignition cable that is to be checked.

Specified values:

• ‒ Replace defective components if specified values are still not attained.

Checking earth supply of output stage

• ‒ → Connect voltage tester V.A.G 1527 B as follows:

• ‒ The LED should light up.

If the LED does not light up:

• ‒ Check for open circuit in the wiring connections:

=> "Current Flow Diagrams, Electrical Fault Finding and Installation locations" binder

• ‒ Rectify open circuit, if necessary.

Checking voltage supply of ignition coils

Note:

Voltage supply to ignition coils is from fuel pump relay.

Test requirements:

• ● → Check fuse S229 is OK (in fuse holder, position 29).

• ‒ → Connect voltage tester V.A.G 1527 B as follows:

• ‒ Operate starter.
• ‒ The LED should light up.

If the LED does not light up:

• ‒ Check for open circuit in the wiring connections:

=> "Current Flow Diagrams, Electrical Fault Finding and Installation locations" binder

• ‒ Rectify open circuit, if necessary.

Checking actuation

• ‒ Pull connectors off all 6 injectors. (then interrogate fault memory).

• ‒ → Connect voltage tester V.A.G 1527 B as follows:

• ‒ Operate the starter for a few seconds.
• ‒ The LED should flash.

If the specified values are not attained:

• ‒ Switch off ignition.
• ‒ Connect the V.A.G 1598/31 test box to wiring harness leading to engine control unit; engine control unit should not be connected .

• ‒ → Check for open circuit and short to earth/positive or earth in the following wiring connections:

• ‒ Rectify any open/short as necessary.

If no wiring fault is detected:

• ‒ Replace engine control unit => Page 24-23.