Audi Workshop Service and Repair Manuals

Checking actuation of power output stages

• ‒ Pull the connectors off all four injectors.

Note:

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

• ‒ Remove the 5-pin connector from the power output stage => Overview of fitting locations - Page 24-5.
• ‒ → Connect the V.A.G 1527 diode test lamp to the following contacts on the power output stage connector:

• ‒ Actuate the starter for a few seconds.

If the specified values are not achieved:

• ‒ Switch the ignition off.
• ‒ Connect the V.A.G 1598/22 test box to the wiring harness for the engine control unit
  =>Page 24-8.
• ‒ → Check the wiring from the 5 pin connector on the power output stage ...
• ‒ .... to the engine control unit for an open circuit and short to positive or earth. Check the earth.

• ‒ If necessary, rectify open circuit or short circuit.

If no fault is detected in the wiring:

• ‒ Connect the 5 pin connector to the power output stage.
• ‒ Pull the 4 pin connector off the power output stage.

• ‒ Connect the V.A.G 1527 diode test lamp to battery positive (+) and to one of the contacts on the 4 pin connector on the power output stage.
• ‒ Operate the starter for a few seconds.

The diode test lamp should start flashing.

• ‒ Carry out the test with all 4 contacts on the power output stage.

The diode test lamp should flash each time.

If the diode test lamp does not flash when testing one or more of the contacts:

• ‒ Replace the power output stage.