GM Service Manual Online
For 1990-2009 cars only

Complaint/Condition

Possible Cause(s)

Correction(s)

High Pitch Whine with High Electrical Loads

Magnetic noise from generator bearing noise

   • 

Verify additional electrical loads from accessories (e.g., cell phone, CB radio, radar detector, etc.).

   • 

Disconnect the regulator connector. If the whine is no longer present, tighten to specification all generator mounting bolts. Reconnect the regulator. If whine still exists, replace the generator.

Squeal, Click, Chirp, or Squeak Seems to Follow Engine RPM

Serpentine belt generator bearing noise or rotor rub

   • 

Spray belt dressing on the serpentine belt. If the noise goes away, replace the belt.

   • 

Check the belt tension and ensure all belted accessories are tight. If the noise is still present, replace the generator.