P0A78-121

L110F HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A78-121: Drive Motor "A" Inverter Performance
P0A78-121 - Drive Motor "A" Inverter Performance

DESCRIPTION

For a description of the inverter, P0A78-266.

MONITOR DESCRIPTION

If the motor inverter detects overvoltage, it transmits an overvoltage signal to the MG ECU. Upon receiving this signal, the hybrid vehicle control ECU illuminates the MIL and sets a DTC.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

CONFIRMATION DRIVING PATTERN

1. Connect the Techstream to the DLC3.

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

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

4. Turn the power switch off.

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

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

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

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

9. Check that the permanent DTCs are cleared.

10. 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.
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
- *1: If any INF codes are output for this DTC, refer to the corresponding diagnostic flowchart.
- P0A78-121 may be set due to a malfunction which also causes DTCs in the preceding table to be set. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a test to attempt to reproduce the problems, and check that no DTCs are output.

B -- GO TO DTC CHART Hybrid Control System
A -- Continue to next step.

2. CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) P0A78-128

NG -- CONNECT SECURELY
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - GENERATOR RESOLVER) P0A78-128

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK GENERATOR RESOLVER P0A78-128

NG -- CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR)
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - MOTOR RESOLVER) P0A78-128

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. CHECK MOTOR RESOLVER P0A78-128

NG -- CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR)
OK -- Continue to next step.

7. CHECK INVERTER WITH CONVERTER ASSEMBLY (GENERATOR CABLE CONNECTION CONDITION) P0A78-128

B -- REPLACE MALFUNCTIONING PARTS

C -- CONNECT SECURELY
A -- Continue to next step.

8. CHECK INVERTER WITH CONVERTER ASSEMBLY (MOTOR CABLE CONNECTION CONDITION) P0A78-128

B -- REPLACE MALFUNCTIONING PARTS

C -- CONNECT SECURELY
A -- Continue to next step.

9. CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (MG1) P0A78-128

NG -- CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (GENERATOR CABLE CONNECTION CONDITION)
OK -- Continue to next step.

10. CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (MG2) P0A78-128

NG -- CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (MOTOR CABLE CONNECTION CONDITION)
OK -- Continue to next step.

11. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) P0A78-128

NG -- CONNECT SECURELY
OK -- Continue to next step.

12. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) P0A78-128

NG -- CONNECT SECURELY
OK -- Continue to next step.

13. CHECK INVERTER WITH CONVERTER ASSEMBLY (HIGH-VOLTAGE CONNECTOR CONNECTION CONDITION)

CAUTION:
Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

(b) Remove the connector cover from the inverter with converter assembly.

OK:

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

(d) Check for arc marks on the terminals of the high-voltage DC connector of the inverter with converter assembly.

Result:

B -- REPLACE MALFUNCTIONING PARTS

C -- CONNECT SECURELY
A -- Continue to next step.

14. CHECK SERVICE PLUG GRIP (CONNECTION CONDITION)

CAUTION:
Be sure to wear insulated gloves.

(a) Visually check the connection of the service plug grip to the HV battery. Remove the service plug grip and check for contamination.

OK:

Dirt or foreign objects have not entered the connection, and there is no evidence of contamination.

NG -- REPLACE SERVICE PLUG GRIP Removal
OK -- Continue to next step.

15. CHECK SERVICE PLUG GRIP

(a) Measure the resistance according to the value(s) in the table below.

Standard resistance:

NG -- REPLACE SERVICE PLUG GRIP Removal
OK -- Continue to next step.

16. CHECK FRAME WIRE

CAUTION:
Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

(b) Disconnect the frame wire from the HV battery junction block.

(d) Measure the resistance according to the value(s) in the table below.

Standard resistance:

(e) Using a megohmmeter set to 500 V, measure the resistance according to the value(s) in the table below.

NOTICE:
Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

Standard resistance:

NG -- REPLACE FRAME WIRE Components
OK -- Continue to next step.

17. INSPECT HV BATTERY JUNCTION BLOCK (SMRB)

CAUTION:
Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

(b) Remove the HV battery junction block from the vehicle Components.

(c) Measure the resistance according to the value(s) in the table below.

Standard resistance:

(d) Measure the resistance according to the value(s) in the table below.

Standard resistance:

NG -- REPLACE HV BATTERY JUNCTION BLOCK Components
OK -- Continue to next step.

18. INSPECT HV BATTERY JUNCTION BLOCK (SMRG)

CAUTION:
Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:

NG -- REPLACE HV BATTERY JUNCTION BLOCK Components

OK -- REPLACE INVERTER WITH CONVERTER ASSEMBLY Installation

19. CHECK CONNECTOR CONNECTION CONDITION (GENERATOR RESOLVER CONNECTOR) P0A78-128

NG -- CONNECT SECURELY
OK -- Continue to next step.

20. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY (MG ECU) - GENERATOR RESOLVER) P0A78-128

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Components

21. CHECK CONNECTOR CONNECTION CONDITION (MOTOR RESOLVER CONNECTOR) P0A78-128

NG -- CONNECT SECURELY
OK -- Continue to next step.

22. CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY (MG ECU) - MOTOR RESOLVER) P0A78-128

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Components

23. CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (GENERATOR CABLE CONNECTION CONDITION) P0A78-128

B -- REPLACE MALFUNCTIONING PARTS

C -- CONNECT SECURELY
A -- Continue to next step.

24. CHECK GENERATOR CABLE P0A78-128

NG -- REPLACE GENERATOR CABLE Components

OK -- REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Components

25. CHECK HYBRID VEHICLE TRANSMISSION ASSEMBLY (MOTOR CABLE CONNECTION CONDITION) P0A78-128

B -- REPLACE MALFUNCTIONING PARTS

C -- CONNECT SECURELY
A -- Continue to next step.

26. CHECK MOTOR CABLE P0A78-128

NG -- REPLACE MOTOR CABLE Components

OK -- REPLACE HYBRID VEHICLE TRANSMISSION ASSEMBLY Components