P0A78-504

P310 HYBRID VEHICLE CONTROL: HYBRID CONTROL SYSTEM: P0A78-504: Drive Motor "A" Inverter Performance

DTC P0A78-504 - Drive Motor "A" Inverter Performance

DESCRIPTION

The inverter converts high-voltage direct current from the HV battery and alternating current for the Motor and Generator. The inverter contains a three-phase bridge circuit, which consists of six power transistors each for the Motor and the Generator, that converts direct current to three-phase alternating current. The MG ECU controls the actuation of the power transistors. The inverter transmits information that is necessary for effecting control, such as the 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.

MONITOR DESCRIPTION

If the motor inverter detects over-voltage, it transmits an over-voltage signal to the MG ECU. Upon receiving this signal, the HV control ECU illuminates the MIL and sets a DTC.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

INSPECTION PROCEDURE
CAUTION:
- Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from 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.
HINT: At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.

PROCEDURE

1. DTC OUTPUT (HV)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
(d) Read output DTCs. Hybrid Control System

Result:
The DTCs shown in the table below are output

HINT:
- Turning the ignition switch to the ON position with the service plug grip and inverter cover removed causes interlock switch system DTC P0A0D-350 to be output.
- P0A78-504 may be output due to a malfunction which causes the DTCs in the table above to be output. In this case, first troubleshoot the output DTCs in the table above. Then, perform a reproduction test to check that no DTCs are output.

YES -- GO TO DTC CHART
NO -- Continue to next step.
2. CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)
CAUTION: Be sure to wear insulated gloves.
(a) Turn the ignition switch off and remove the service plug grip. Hybrid Control System

NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.
(b) Remove the inverter cover. Components

NOTICE:
- Wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
- Prevent water in the reservoir 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.

(c) Check the connections of the MG ECU connectors.
OK:
Connectors are connected securely and there is no poor connection.
NG -- CONNECT SECURELY
OK -- Continue to next step.
3. INSPECT HV RELAY ASSEMBLY (SMR2)
CAUTION: Be sure to wear insulated gloves and protective goggles.
(a) Check that the service plug grip is removed.
(b) Remove the HV relay assembly from the vehicle. Components

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

NG -- REPLACE HV RELAY ASSEMBLY
OK -- Continue to next step.
4. INSPECT HV RELAY ASSEMBLY (SMR3)
CAUTION: Be sure to wear insulated gloves.
(a) Check that the service plug grip is removed.

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

NG -- REPLACE HV RELAY ASSEMBLY
OK -- Continue to next step.
5. CONFIRM INFORMATION (EXCLUSIVE INFO 4)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position and check for HV system DTC P0A0D-350 by following the prompts on the Techstream screen.
HINT: Turning the ignition switch to the ON position with the service plug grip and inverter cover removed causes interlock switch system DTCs to be output.
(c) Display freeze frame data corresponding to DTC P0A94 and select the information.
(d) Select INF code 556 and read "Exclusive Information 4".
Result::

B -- CHECK HARNESS AND CONNECTOR (MG ECU - REAR MOTOR RESOLVER)
A -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (MG ECU - MOTOR RESOLVER)

(a) Disconnect the I22 connector from the MG ECU.
(b) Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
Standard Voltage:

(c) Turn the ignition switch off.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK CONNECTION CONDITION OF MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT)
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (MG ECU - GENERATOR RESOLVER)

(a) Disconnect the I22 connector from the MG ECU.
(b) Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
Standard Voltage:

(c) Turn the ignition switch off.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK CONNECTION CONDITION OF GENERATOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT)
OK -- Continue to next step.
8. CHECK CONNECTION CONDITION OF MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A3F

NG -- CONNECT SECURELY
OK -- Continue to next step.
9. CHECK CONNECTION CONDITION OF GENERATOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A4B

NG -- CONNECT SECURELY
OK -- REPLACE W/ CONVERTER INVERTER ASSEMBLY
10. CHECK HARNESS AND CONNECTOR (MG ECU - REAR MOTOR RESOLVER)

(a) Disconnect the I21connector from the MG ECU.
(b) Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
Standard Voltage:

(c) Turn the ignition switch off.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- CHECK CONNECTION CONDITION OF REAR MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT)
OK -- Continue to next step.
11. CHECK CONNECTION CONDITION OF REAR MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A45

NG -- CONNECT SECURELY
OK -- REPLACE W/ CONVERTER INVERTER ASSEMBLY
12. CHECK CONNECTION CONDITION OF MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A3F

NG -- CONNECT SECURELY
OK -- Continue to next step.
13. INSPECT MOTOR RESOLVER

(a) Disconnect the M14 motor resolver connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

(c) Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
NOTE: 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 HYBRID VEHICLE TRANSAXLE ASSEMBLY
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR
14. CHECK CONNECTION CONDITION OF GENERATOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A4B

NG -- CONNECT SECURELY
OK -- Continue to next step.
15. INSPECT GENERATOR RESOLVER
(a) Remove the w/ converter inverter assembly. Components

(b) Disconnect the M13 generator resolver connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

(d) Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
NOTE: 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 HYBRID VEHICLE TRANSAXLE ASSEMBLY
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR
16. CHECK CONNECTION CONDITION OF REAR MOTOR RESOLVER CONNECTOR (LOOSENESS AND POOR CONTACT) P0A45

NG -- CONNECT SECURELY
OK -- Continue to next step.
17. INSPECT REAR MOTOR RESOLVER

(a) Disconnect the M18 rear motor resolver connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:

NG -- REPLACE REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR