Detroit DD13 EPA07 (2007-09) Fault Code: SPN 636 FMI 4 (MCM) Crankshaft Position Sensor Shorted to Ground

NOTE: If the sensor is removed, be sure to check the sensor tip for metal debris and clutch material. Clean it if necessary.

PROBABLE CAUSES:
1. Crankshaft sensor connector/harness.
2. Crankshaft sensor.