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.
- Clean and tighten all ground straps between the engine and the frame.
- Try the following fixes:
- If noise is still present, inspect the charging system Refer to A Diagnostic System Check - Starting and Charging in Engine Electrical.
- If the charging system is functioning normally, examine the technical service bulletins on generator whine.
- Install a filter GM P/N 1224205 in the battery feed to the radio.
- Try installing the filter with the following variations if noise is not eliminated.
1. Remove the ground to the filter.
2. Reverse the filter so the two wire side is toward the radio with the ground wire attached to a good ground.
3. Remove the ground from the filter.
- If noise is still present, install another filter GM P/N 1224205 in the ignition feed to the radio. Install using 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 in its place.
- Remove any unneeded filters after repair, before reassembling the vehicle.