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From 08/2009





HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM: P0A78-202: Drive Motor "A" Inverter Performance
P0A78-202 - Drive Motor "A" Inverter Performance

DESCRIPTION

The inverter contains a three-phase bridge circuit, which consists of six power transistors (IGBTs) each for MG1, MG2 and MGR. The inverter converts high-voltage direct current from the HV battery into three-phase alternating current for MG1, MG2 and MGR; it also converts three-phase alternating current supplied by MG1, MG2 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 an inverter voltage sensor, which is built into the inverter, to detect boosted high voltage to allow control of the voltage boost.

The MG ECU monitors the inverter voltage sensor and detects the following malfunctions.





MONITOR DESCRIPTION

The MG ECU monitors the motor inverter electric current. If the current exceeds the threshold for a specified period of time, the power management control ECU (HV CPU) will illuminate the MIL and set a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





COMPONENT OPERATING RANGE





CONFIRMATION DRIVING PATTERN





- Connect the Techstream to the DLC3.

- Turn the power switch on (IG) and turn the Techstream on.

- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

- Turn the power switch off.

- Turn the power switch on (IG) and check that there are no abnormalities (abnormal sounds, coolant leaks, DTC output, etc).

- Turn the power switch on (READY) and turn the Techstream on. [A]

- With the shift lever in P, wait for several seconds.

- Enter the following menus: Powertrain / Hybrid Control / Trouble Codes. [B]

- Check that permanent DTCs are cleared.

- If the permanent DTCs are not cleared, perform a universal trip, and then check for permanent DTCs again.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
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 for 10 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.
NOTICE:
- DTC P0A78-202 is stored after any of DTCs P0A78-113, 128, 284, 286, 287, 505, 506, 806, 807 and 808 are stored. After troubleshooting and repairing DTC P0A78-202, be sure to troubleshoot all the other DTCs.
- Depending on the conditions in which the vehicle is being operated when a short circuit occurs in the inverter with converter assembly, the hybrid vehicle transaxle assembly may be affected. As this DTC is stored if a short circuit occurs in the inverter with converter assembly, it is necessary to perform a road test to check the hybrid vehicle transaxle assembly. If problems are found, replace the malfunctioning parts.
- After completing the repair, including the repair of previously output DTCs, drive the vehicle at a speed of approximately 25 mph (40 km/h) for 1 minute and check that DTC P0A90-251 (Drive Motor "A" Performance) is not output. If DTC P0A90-251 (Drive Motor "A" Performance) is output, replace the hybrid vehicle transaxle assembly.
HINT
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

PROCEDURE

1. CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY P0A78

NG -- REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY
OK -- Continue to next step.

2. REPLACE INVERTER WITH CONVERTER ASSEMBLY

(a) Replace the inverter with converter assembly Components.

NEXT -- CHECK DTC OUTPUT (HV)

3. REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

(a) Replace the hybrid vehicle transaxle assembly Components.

NEXT -- Continue to next step.

4. REPLACE INVERTER WITH CONVERTER ASSEMBLY

(a) Replace the inverter with converter assembly Components.

NEXT -- Continue to next step.

5. CHECK DTC OUTPUT (HV)

(a) Check the other DTCs that were output together with DTC P0A78-202.

Result:





NOTICE:
DTC P0A78-202 is stored after any of DTCs P0A78-113, 128, 284, 286, 287, 505, 506, 806, 807 and 808 are stored. After troubleshooting and repairing DTC P3246-202, be sure to troubleshoot all the other DTCs.

NEXT -- GO TO DTC CHART Hybrid Control System
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