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 Crankshaft Position Sensor Signal With Lab
- Checking Intermittent Camshaft Position Sensor 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