Glow Plug System: Testing and Inspection

Glow plug system, checking

Special tools, testers and auxiliary items

Fluke 83 multimeter (or equivalent)
VW1594 connector test kit

Test requirements

Battery positive voltage (B+) = 11.5 volts minimum
Ignition switched OFF
Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- OK
Glow plug fuse -S125- OK

Note: The production "control" number "180" must appear on the housing of the glow plug relay.

Checking





- Disconnect harness connector from Engine Coolant Temperature (ECT) sensor -1-.

Note: A "cold engine" condition is simulated when the ECT harness connector is disconnected, and then the ignition key is switched on for the appropriate glow period.

- Disconnect glow plug harness connector.
- Switch ignition on.
- Switch multimeter (Fluke 83 or equivalent) to 20 volt (VDC) measuring range.
- Connect multimeter using adapters from VW1594 connector test kit, and check for voltage between:
Cyl. 1 glow plug connector and vehicle Ground
Cyl. 3 glow plug connector and Ground
Specification: Battery voltage for approx. 20 secs

If there is no voltage:
- Troubleshoot glow plug system
- Erase DTC memory and re-create readiness code.