Test F: Generator Noisy

Check For Accessory Drive Noise

Check the accessory drive belt for damage and correct installation. Check the accessory mounting brackets and generator pulley for looseness or misalignment. Is the accessory drive okay? If yes, if equipped with a One-Way Clutch (OWC) pulley, go to next step. If not equipped with a OWC pulley, go to step 3 . If no, repair as necessary. Test the system for normal operation.

Check One-Way Clutch (OWC) Pulley

With the Front-End Accessory Drive (FEAD) belt removed, spin the OWC pulley in a clockwise direction, then reverse the direction of the pulley by spinning it in a counterclockwise direction. Does the OWC pulley engage with the rotor when spun in a clockwise direction and free-wheel when spun in a counterclockwise direction with minimal noise as compared to a known good vehicle? If yes, go to next step. If no, install a new generator assembly with OWC pulley. See GENERATOR under REMOVAL & INSTALLATION. Test the system for normal operation.

Check Generator Mounting

Check the generator mounting for loose bolts or misalignment. Is the generator mounted correctly? If yes, go to next step. If no, repair as necessary. Test the system for normal operation.

Check Generator For Excessive Electrical Noise

Disconnect generator connector C102b (Black/Orange wire). Start engine. With the engine running, determine if the generator is still noisy. Is the noise still present? If yes, go to next step. If no, install a new generator. See GENERATOR under REMOVAL & INSTALLATION. Test the system for normal operation.

Check Generator For Mechanical Noise

Turn all accessories off. With the engine running, use a stethoscope or equivalent listening device to probe the generator for unusual mechanical noise. Is the generator the noise source? If yes, install a new generator. See GENERATOR under REMOVAL & INSTALLATION. Test the system for normal operation. If no, diagnose the source of the engine noise.