Testing glow plug relay -J52 and activation: Audi 1.9 TDI (AJM, ASZ, ATD, ATJ, …)

ATD AXR
Special tools and workshop equipment required

V.A.G 1526 A
V.A.G 1527 B
V.A.G 1594 A
V.A.G 1598/31
VAS 5051 with VAS 5051/1

Note:

The glow plug relay -J52 is located in the central electrics on the left of the driver's footwell, plug-in position 4.

Test requirement:

Battery voltage not less than 12.7 V

Testing operation of glow plug relay

Remove engine cover panel => Page 28-2.
Pull glow plug connector rail off glow plugs.
Connect voltage tester V.A.G. 1527 B between one of the glow plug connectors and engine earth.
Remove storage compartment on driver's side.

=> General body repairs, Interior; Repair group 68; Storage compartments, covers; Removing driver's storage compartment
General body repairs, Interior
Storage compartments, covers
Removing driver's storage compartment

Start final control diagnosis and activate glow plug relay
=>Page01-64.
The glow plug relay should pick up audibly and perceptibly; the LED should light up

Press the ◂button to exit from function "03 - Final control diagnosis".
Select diagnosis function "06 - End output".
Switch off ignition.

A - If the relay does not pick up:

Test voltage supply to glow plug relay => Page 28-7.
Test activation of glow plug relay => Page 28-7.

B - If the relay picks up but the LED does not light up:

Test wiring connection between relay panel terminal 23 to glow plugs.

Testing voltage supply to glow plug relay

Connect multimeter (voltage measurement range) to earth and contact 17 on relay panel.
Specification: approx. battery voltage

If the specification is not obtained:

Replace central electrics unit

Testing activation of glow plug relay

Switch off ignition.
Connect test box V.A.G 1598/31 to wiring harness for engine control unit.Do notconnect to the engine control unit itself:
Connecting test box to engine control unit without protective housing=>Page 23-49.
Connecting test box to engine control unit with protective housing=>Page 23-51.

Bridge contacts 4 and 42 on the test box using test leads from adapter set V.A.G 1594 A.
Switch on ignition.

The glow plug relay should pick up. (Relay is located in plug-in position 4 in central electrics on left of driver's footwell).

If the relay picks up now but not during the final control diagnosis:

Replace engine control unit
Removing and installing engine control unit without protective housing=>Page 23-57.
Removing and installing engine control unit with protective housing=>Page 23-60.

If the relay does not pick up:

Switch off ignition.
Disconnect cable bridge.
Disconnect glow plug relay.

Connect multimeter (voltage measurement range) between earth and contact 19 on relay panel.
Switch on ignition.
Specification: approx. battery voltage

If the specification is not obtained:

Check the wiring.

=> Current flow diagrams, Electrical fault finding and Fitting locations binder

If the specification is obtained:

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

Central electrics on left of driver's footwell, relay position 4 / Contact · Test box V.A.G 1598/31 / / / Socket
16 · 42

Rectify any open/short circuit as necessary.

If no fault is found:

Fit a new glow plug relay.
Reconnect the engine control unit.