P0A78-807 - Drive Motor "A" Inverter Performance

L110 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A78-807: Drive Motor "A" Inverter Performance
P0A78-807 - Drive Motor "A" Inverter Performance

DESCRIPTION

For a description of the inverter, P0A78.

If an abnormal amount of current flows through the motor inverter, the MG ECU detects it and sends a signal to inform the hybrid vehicle control ECU of the malfunction.





MONITOR DESCRIPTION

The MG ECU monitors the motor inverter electric current. If the current exceeds the threshold for a specified period of time, the hybrid vehicle control ECU will illuminate the MIL and set a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





INSPECTION PROCEDURE

CAUTION:
- Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
- After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting, check the voltage at the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
HINT
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK DTC OUTPUT (HV)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.

(d) Check if DTCs are output.

Result:





HINT
P0A78-807 may be set due to a malfunction which also causes DTCs in the table above to be set. In this case, first troubleshoot the output DTCs in the table above. Then, perform a test to attempt to reproduce the problems, and check that no DTCs are output.

YES -- GO TO DTC CHART
NO -- Continue to next step.

2. CHECK CONNECTOR CONNECTION CONDITION

(a) Check the connection of the low voltage connector of the inverter with converter assembly.





Result:

The connector is connected securely and there are no contact problems.

NG -- CONNECT SECURELY

OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Service and Repair