Pinpoint Test F: The Generator Is Noisy

Pinpoint Test






Pinpoint Test F: The Generator is Noisy

Refer to Wiring Diagrams Set 12, Charging System for schematic and connector information. Electrical Diagrams

Normal Operation

The generator is belt-driven by the engine accessory drive system. There are many sources of generator noise: bearing noise, electrical fault noise and/or belt pulley misalignment. A generator with certain types of diode or stator failures may also produce an audible noise.

This pinpoint test is intended to diagnose the following:

- Accessory drive belt

- Loose bolts/brackets

- Generator/pulley

PINPOINT TEST F : THE GENERATOR IS NOISY
F1 CHECK FOR ACCESSORY DRIVE BELT NOISE AND LOOSE MOUNTING BRACKETS

- Ignition OFF.

- Check the accessory drive belt and tensioner for damage and correct installation.

- Check the accessory mounting brackets and generator pulley for looseness or misalignment.

Is the accessory drive OK?

Yes
GO to F2.
No
REPAIR as necessary. TEST the system for normal operation.

F2 CHECK THE GENERATOR MOUNTING

- Check the generator mounting for loose bolts or misalignment.

Is the generator mounted correctly?

Yes
GO to F3.
No
REPAIR as necessary. TEST the system for normal operation.

F3 CHECK THE GENERATOR FOR NOISE

- With the engine running, use a stethoscope or equivalent listening device to probe the generator and the accessory drive area for unusual mechanical noise.

Is the generator the noise source?

Yes
INSTALL a new generator. REFER to the Generator procedure.
No
REFER to Engine to diagnose the source of the engine noise.