Audi Workshop Service and Repair Manuals

Special tools and workshop equipment required

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

With the ignition switched on, the injection system receives its voltage supply via terminal 30 voltage supply relay -J317.

In order for relay -J317 to close, a voltage must be applied to the Diesel direct injection system control unit via terminal 15. This means that relay -J317 is only earthed (via the Diesel direct injection system control unit) if a voltage is applied to the control unit via terminal 15.

Note:

→ Fitting location of terminal 30 voltage supply relay -J317:plug-in position 3 on relay and fuse carrier in electronics box in plenum chamber.

Test requirement:

• ● Battery voltage not less than 12.7 V

Test sequence

• ‒ Connect test box V.A.G 1598/31 to wiring harness for engine control unit. Do not connect to the engine control unit itself.
  => Page 23-37.

Testing earth supply

• ‒ Connect multimeter (voltage measurement range) as follows:

• ‒ Specification: approx. battery voltage

If the specifications are not obtained:

• ‒ Check wiring connections according to current flow diagram.

Checking voltage supply (terminal 15)

• ‒ Connect multimeter (voltage measurement range) as follows:

• ‒ Switch on ignition.
• ‒ Specification: approx. battery voltage

If the specification is not attained:

• ‒ Test wiring for open circuits and rectify if necessary.

Testing voltage supply (terminal 30)

• ‒ → Connect sockets 4 and 18 of test box to each other using auxiliary cable from V.A.G 1594 A.

• ‒ → The relay -J317 (plug-in position 3 on relay and fuse carrier in electronics box in plenum chamber) should pick up audibly and perceptibly

If the relay does not pick up:

• ‒ Check relay -J322 => Page 23-50.

If the relay picks up

• ‒ Connect multimeter (voltage measurement range) as follows:

• ‒ → Test the following wiring connections for open circuits:

If no fault is detected in the wiring:

• ‒ Test relay -J322.

Testing terminal 30 voltage supply relay -J317

Requirements for test:

• ● Earth connection and voltage connection of engine control unit okay
• ● Engine control unit connected.
• ● Relay clicks when ignition is switched on.

• ‒ Unplug relay -J317 from relay panel (plug-in position 3 on relay and fuse carrier in electronics box in plenum chamber).

• ‒ → Connect multimeter (voltage measurement range) as follows:

• ‒ Specification: approx. battery voltage

If the specification is not attained:

• ‒ Test for open circuits in wiring, rectify if necessary.
• ‒ Connect multimeter (voltage measurement range) as follows:

• ‒ Switch on ignition.
• ‒ Specification: approx. battery voltage

If the specification is not attained:

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

If no wiring fault is detected:

• ‒ Fit a new engine control unit => Page 23-40.

If no wiring fault is detected and no voltage was present between contacts 1+2:

• ‒ Renew relay -J317.