DTC 510

HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM: P0A78-510: Drive Motor "A" Inverter Performance
P0A78-510 - Drive Motor "A" Inverter Performance

DESCRIPTION

The inverter contains a three-phase bridge circuit, which consists of six power transistors (IGBTs) each for MG1 and MG2. The inverter converts high-voltage direct current from the HV battery into three-phase alternating current for MG1 and MG2; it also converts three-phase alternating current supplied by MG1 and MG2 into direct current for the HV battery. The MG ECU controls the actuation of the power transistors (IGBTs). The inverter transmits information necessary for control, such as amperage and voltage, to the MG ECU.





The MG ECU uses a voltage sensor, which is built into the inverter, to detect boosted high voltage (VH) to allow control of the voltage boost.

The inverter voltage sensor outputs voltage that varies between 0 and 5 V in accordance with the changes in the boosted voltage. The higher the boosted voltage, the higher the sensor output voltage, and the lower the boosted voltage, the lower the sensor output voltage.

The MG ECU monitors the inverter voltage and detects malfunctions.

If the inverter receives a motor gate shutdown signal from the MG ECU, it will turn all power transistors off which are activating MG2 to forcibly stop MG2 operation.

The MG ECU monitors motor gate shutdown signals and detects a malfunction.





HINT
* When P0A78-510 has been stored, the hybrid system cannot be restarted until the DTC is cleared.
* If the problem symptom cannot be reproduced, leaving the vehicle with the power switch on (READY) and neutral (N) selected for 1 minute will make it easier to reproduce the symptom.
MONITOR DESCRIPTION

The MG ECU monitors the current to MG2. If current passes to MG2 while the vehicle is stopped with the power switch on (IG) or neutral (N) selected, the MG ECU will detects an abnormality. 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

PROCEDURE

1. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) P0343

NG -- CONNECT SECURELY

OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Components