Diagnostic Fault Information
The hybrid drive motor generator battery has very few moving parts. The moving parts are the 3 high voltage (HV) contactor relays, the hybrid drive motor battery vent fan relay, and the vent fan motor.
Circuit/System Description
The hybrid drive motor generator battery is an air cooled component. The hybrid drive motor generator battery vent fan and relay are located inside the hybrid drive motor generator battery assembly. The hybrid drive motor battery vent fan relay controls
the supply voltage to the cooling vent fan motor. The control circuit for the vent fan relay and the vent fan speed are controlled by the battery energy control module (BECM).
The hybrid drive motor generator battery contains 3 high voltage contactor relays that allow the high voltage (HV) DC batteries to be connected to the vehicle. The three HV contactor relays are a positive HV contactor relay, negative HV contactor
relay and the inverter current limit relay. These relays close and open in a certain sequence controlled by the BECM. The control circuit for the relays use a common ground and the BECM provide voltage to turn them on and off individually.
Circuit/System Verification
- Ignition ON, command the hybrid drive motor battery fan ON and OFF with a scan tool. The fan should not make objectionable noise. Some noise is considered normal.
- Ignition ON, command the HV contactors ON and OFF with a scan tool one at a time. The contactors should not make objectionable noise. Some noise is considered normal.
Circuit/System Testing
- Ignition OFF, inspect the hybrid drive motor battery air inlet and outlet for debris, or for a restriction.
| ⇒ | If debris or a restriction is found, repair as necessary. |
- Check for loose and vibrating duct work.
| ⇒ | If loose or vibrating duct work is found, repair as necessary. |
- Ignition ON, command the hybrid drive motor battery fan ON and OFF with a scan tool. The fan should not make objectionable noise.
| ⇒ | If the fan makes excessive noise, replace the hybrid drive motor battery fan. |
- Command the HV contactors ON and OFF with a scan tool one at a time. The HV contactors should not make objectionable noise, compare to like vehicle.
| ⇒ | If the HV contactors make objectionable noise check the contactor mounting insulators and torque of mounting fasteners. Tighten and repair as necessary. |
| ⇒ | If the HV contactor has objectionable noise, replace the HV contactor. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the repair.
