Drive Motor Generator Battery Noise

Drive Motor Generator Battery Noise

Diagnostic Fault Information

The hybrid drive motor battery has very few moving parts. The moving parts are the 3 high voltage (HV) contactors, the hybrid drive motor battery cooling fan relay, and the cooling fan motor.

Circuit/System Description

The hybrid drive motor battery is an air cooled component. The hybrid drive motor battery fan and relay are located inside the hybrid drive motor battery assembly. The hybrid drive motor battery cooling fan relay controls the cooling fan motor speed. The relay is controlled by the battery energy control module (BECM).

The hybrid drive motor battery contains 3 relays that allow the high voltage (HV) DC batteries to be connected to the vehicle. The three HV relays are a positive HV relay, negative HV relay and pre-charge HV 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

1. Ignition ON, command the hybrid drive motor battery fan ON and OFF with a scan tool. The fan should not make noise.
2. Ignition ON, command the HV contactors ON and OFF with a scan tool one at a time. The contactors should not make excessive noise.

Circuit/System Testing

1. 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.

2. Check for loose and vibrating duct work.

^ If loose or vibrating duct work is found, repair as necessary.

3. Ignition ON, command the hybrid drive motor battery fan ON and OFF with a scan tool. The fan should not make noise.

^ If the fan makes noise, replace the hybrid drive motor battery fan.

4. Command the HV contactors ON and OFF with a scan tool one at a time. The HV contactors should not make excessive noise (compare to like vehicle).

^ If the HV contactors make excessive noise check the contactor mounting insulators and torque of mounting fasteners. Tighten and repair as necessary.
^ If the HV contactor has excessive noise, replace the HV contactor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair. Verification Tests

Hybrid Drive Motor Battery Fan Replacement. Refer to Hybrid Drive Motor Battery Fan Replacement.