Glow Plugs, Checking

Special Tools, Testers And Auxiliary Items:

- VAG 1527B LED tester
- VW 1594 Adaptor kit
- 3220 Flexible wrench

Test Conditions:

- Battery voltage 11.5 Volts minimum
- Ignition switched OFF
- Diesel direct injection system control unit (J248) OK
- Glow plug fuse (S125) OK
- Production number "180" must appear on the reverse side of the glow plug relay






Test Procedure:

- Disconnect Engine Coolant Temperature sensor harness connector -1-

NOTE: A "cold" engine condition is simulated when the G62 harness connector is disconnected and then the ignition is switched ON for the appropriate glow period.

- Disconnect glow plug harness connector
- Switch ON ignition
- Switch Fluke 83 multimeter to 20 Volt range
- Connect multimeter between cyl. 1 glow plug connector and vehicle Ground and between cyl. 3 glow plug connector and Ground using jumper wires from VW 1594 adaptor kit
Specification: Battery voltage for approx. 20 secs

If no voltage exists:

- Troubleshoot system using wiring diagrams
- Erase DTC memory and recreate readiness code

If voltage present:

- Switch OFF ignition
- Disconnect glow plug harness connector






- Connect VAG 1527B LED tester to battery positive (+) using jumper wires from VW 1594 adaptor kit
- Place LED tester on each glow plug one after the other
Diode lights up: glow plug OK
Diode does not light up: replace glow plug
- Remove and install glow plugs using 3220 flexible wrench
Tightening torque: 15 Nm (11 ft lb).
- Erase DTC memory and recreate readiness code