Test B: Unusual Starter Noise

PINPOINT TEST B: UNUSUAL STARTER NOISE

B1-B3:

Normal Operation
Under normal operation the power distribution box (PDB) supplies constant power to the starter relay on circuit 30-BB13 (RD) through fuse 121 (30A). When the key is placed in the START position, with the vehicle in PARK or NEUTRAL, the TR sensor provides power on circuit 50S-BB12 (GY) and the instrument cluster provides ground on circuit 31S-BB12 (BK/YE). The coil of the relay is energized and sends power to the starter motor on circuit 50-BB10 (GY/BK).

Possible Causes
Unusual starter noise can be caused by the following:
- loose starter motor mounting bolts or brackets.
- worn or damaged flywheel ring gear.
- worn or damaged starter motor drive gear.