Generator Whine Concerns

^ Inspect the ground terminal on the battery.
^ Inspect for coated mounting bolts on the generator bracket.
^ Inspect for a faulty mounting of the generator to the engine.
^ Ensure that all of the ground straps between the engine and the frame are clean and tight.
^ Try the following suggestions:
1. If the noise is still present, inspect the charging system. Refer to Generator Not Operating Properly in Starting and Charging.
2. If the charging system functions normally, inspect for technical service bulletins pertaining to generator whine.
3. Install a filter GM P/N 1224205 in the battery feed to the radio.
4. Install the filter with the following variations if the noise is not eliminated:
^ Install the filter with the single wire side toward the radio and the ground wire attached to a good ground.
^ Remove the ground to the filter.
^ Reverse the filter so the 2 wire side is toward the radio with the ground wire attached to a good ground.
^ Remove the ground to filter.
5. If the noise is still present, install another filter GM P/N 1224205 in the ignition feed to the radio. Use the same variations as the first filter.
If the installation of this filter causes turn ON or turn OFF delays or other noticeable performance concerns, remove the filter and install a 0.47 mF capacitor to ground instead.
6. Remove any unneeded filters after the repair before you reassemble the vehicle.