P1391

Tests 1 - 2:

Tests 3 - 7:

Tests 8 - 11:

Tests 12 - 14:

SYMPTOM
P1391-INTERMITTENT LOSS OF CMP OR CKP

WHEN MONITORED
Engine running or cranking.

SET CONDITION
When the failure counter reaches 20 for 2 consecutive trips.

POSSIBLE CAUSES
- Wiring harness inspection
- Tone wheel/pulse ring inspection
- Wiring harness inspection
- Tone wheel/pulse ring inspection
- Checking intermittent CKP signal with LAB
- Checking intermittent CMP signal with LAB
- Checking intermittent CKP wiring with LAB scope
- Checking intermittent CMP wiring with LAB scope
- Intermittent condition
- Camshaft position sensor
- Crankshaft position sensor