Generator Functional Test (1989 & 1990)
NOTE:
The following applies to steps on the generator functional check chart. See Fig 1
.
- At key ON, engine OFF, the `Battery No Charge' telltale should be on.
- If the Battery `Volts' telltale is on with the engine running, refer to Battery `Volts' telltale diagnosis.
- Always diagnose Codes B410, B411, and B412 before performing generator functional check. The trouble code charts will check the BCM's ability to detect generator faults and to control generator operation.
- This step checks for the generator overcharging the battery. Generator overcharging the battery may be accompanied by Code B412 (either current or history) and `Battery Volts High' message on the Driver Information Center. Code B410 accompanied by `Service Electrical System' message may also set. Visual signs of battery overcharge may include electrolyte leakage from the battery vents, low electrolyte level indicated by a yellow battery eye, or low electrolyte levels seen through the side of the battery case.
- This step checks for proper generator current output. Generator output below 90 amps at 1500 RPM may result in undercharging of the battery. Generator undercharging of the battery may be accompanied by a current or history Code B411 and `Battery Volts Low' message on the Driver Information Center. Code B410 accompanied by `Service Electrical System' message may also set.