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

Checking internal resistance

• ‒ Unplug connector on injector to be checked.

• ‒ → Connect multimeter to valve to measure resistance
• ‒ Specified value: 13.5 ... 15.5 ω

When the engine is at operating temperature the resistance is increased by approx. 4...6 ω.

If the specified value is not attained:

• ‒ Replace injector.

Checking voltage supply

Test requirements:

• ● Fuel pump relay OK; checking .
• ● → Fuse S232 (position 32) for injectors OK.

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

• ‒ Unplug connector on injector to be checked.

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

• ‒ Switch on the ignition.
• ‒ The LED should light up

If the LED does not light up:

• ‒ → Check wiring between contact 1 and fuse S232 (on position 32) for injectors for open circuit:

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

• ‒ Rectify open circuit, if necessary

If the LED lights up:

Checking actuation

• ‒ → Push back rubber grommet of plug -arrow- of injector but leave plug attached.
• ‒ Connect up voltage tester V.A.G 1527 B between receptacles 2 (signal) and 1 (positive).
• ‒ Operate the starter briefly (the engine may start).
• ‒ The LED should flash.

If LED does not flash:

• ‒ Connect the V.A.G 1598/31 test box to wiring harness leading to engine control unit; the 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 the wiring is OK:

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