Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

NOTE:

If a glow plug is replaced and the tip is missing or burned off, the cylinder head must be removed and all debris be cleaned out of the cylinder.

Ignition OFF, disconnect the harness connector at the appropriate E12 Glow Plug, Ignition ON.
Glow plugs not commanded ON, verify that a test lamp does not illuminate between the appropriate Glow Plug Supply Voltage circuit terminal 1 and ground.
- If the test lamp illuminates
1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Ignition ON.
3. Test for less than 1 V between the appropriate glow plug supply voltage circuit and ground.
  - If 1 V or greater, repair the short to voltage in the circuit.
  - If less than 1 V, replace the K20 Engine Control Module.
- Go to next step : If the test lamp does not illuminate
Command the Glow Plugs ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp does not turn ON and OFF
1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the appropriate glow plug supply voltage circuit and ground.
  - If less than infinite resistance, repair the short to ground in the circuit.
  - Go to next step : If infinite resistance.
3. Test for less than 2Ω in the glow plug supply voltage circuit end to end.
  - If 2Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2Ω, replace the K20 Engine Control Module.
- Go to next step : If the test lamp turns ON and OFF
Replace the appropriate E12 Glow Plug.