Glow Plug Control Circuit Preglow Fault

Test 1 - 2:

Test 3 - 6:

SYMPTOM
P2537 - GLOW PLUG CONTROL CIRCUIT PREGLOW FAULT

POSSIBLE CAUSES
- Engine control module
- Glow plug control signal circuit open
- Glow plug control signal circuit shorted to ground
- Glow plug control signal circuit shorted to voltage
- Glow plug module
- Intermittent condition