P0A79-691

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A79-690: Drive Motor "B" Inverter Performance

DTC P0A79-690 - Drive Motor "B" Inverter Performance

DTC P0A79-691 - Drive Motor "B" Inverter Performance

DESCRIPTION

The inverter contains three-phase bridge circuits, which consist of six power transistors each for MG2, MG1 and MGR. The inverter converts high-voltage direct current from the HV battery into three-phase alternating current for MG2, MG1 and MGR, it also converts three-phase alternating current supplied by MG2, MG1 and MGR 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 for boost control.
The inverter voltage sensor outputs voltage that varies between 0 and 5 V in accordance with the changes in the high voltage. The higher the high-voltage, the higher the output voltage, and the lower the high-voltage, the lower the output voltage.
The MG ECU monitors the inverter voltage and detects a malfunction.


If the motor inverter circuit is open or shorted, or if the circuit overheats, the information will be transmitted from the inverter to the RFIV terminal of the MG ECU via the rear motor inverter fail signal line.
The MG ECU monitors the rear motor inverter fail signal line and detects a malfunction.
HINT: The term "drive motor B" indicates MGR.





MONITOR DESCRIPTION

The MG ECU monitors the rear motor inverter fail (RFIV) signal line. If the MG ECU detects an open or short in the RFIV signal circuit, 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 5 minutes before touching any of the high-voltage connectors or terminals. After waiting for 5 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
HINT: Waiting for at least 5 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK CONNECTOR CONNECTION CONDITION (MG ECU CONNECTOR)
CAUTION: Be sure to wear insulated gloves.
(a) Turn the power switch off.
(b) Remove the service plug grip Removal.
NOTE: After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
(c) Remove the inverter cover Removal.
NOTICE:
- Wrap the round interlock terminal for the inverter cover with insulating tape to prevent it from shorting to ground.
- Be sure to prevent coolant in the inverter reserve tank from entering the inverter.
- Removing the inverter cover causes the MG ECU board to be exposed. Therefore, temporarily install the inverter cover for each area to be inspected.





(d) Check the connections of the MG ECU connectors.
OK:
The connectors are connected securely and there are no contact problems.
NG -- CONNECT SECURELY
OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY