DTC    P0A78-504    Drive Motor "A" Inverter Performance

for Preparation Click here


DESCRIPTION

Refer to the description of the inverter. (Click here)

DTC No.
INF Code
DTC Detection Condition
Trouble Area
P0A78
504
Motor inverter overvoltage signal detection (overvoltage by HV transaxle assembly malfunction)
  1. Wire harness or connector
  2. HV relay assembly
  3. w/ converter inverter assembly (MG ECU)
  4. Rear traction motor w/ transaxle assembly
  5. Hybrid vehicle transaxle assembly

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.

INSPECTION PROCEDURE

CAUTION:
  1. 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.
  2. 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.

1.READ OUTPUT DTC (HV)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to the ON position.

  1. Select the following menu items: Powertrain / Hybrid Control / DTC.

  1. Read output DTCs. (Click here)

    Result:
    The DTCs shown in the table below are output:

    DTC No.
    		INF Code
    		Detection Item
    P0A3F
    		243
    		Motor resolver circuit
    P0A40
    		500
    		Motor resolver output is out of normal range
    P0A41
    		245
    		Motor resolver malfunction (Low)
    P0A45
    		669
    		Interphase short in Rear Motor resolver circuit
    P0A46
    		671
    		Rear motor resolver output is out of normal range
    P0A47
    		670
    		Rear motor resolver malfunction (Low)
    P0A4B
    		253
    		Generator resolver circuit
    P0A4C
    		513
    		Generator resolver output is out of normal range
    P0A4D
    		255
    		Generator resolver malfunction (Low)
    P0A78
    		266, 280
    		Motor inverter function malfunction
    P0A94
    		558, 559, 588, 589
    		Boost converter circuit malfunction
    P0A95
    		123
    		High voltage fuse blown out
    P0AA1
    		226
    		SMR+ stuck closed
    P0AA2
    		227
    		SMR+ stuck open
    P0AA4
    		228
    		SMR- stuck closed
    P0AA5
    		229
    		SMR- stuck open
    P3004
    		803
    		High-current wiring malfunction

    HINT:
    1. 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.
    2. 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


2.CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)

CAUTION:
Be sure to wear insulated gloves.

  1. Turn the ignition switch off and remove the service plug grip. (Click here)

    NOTICE:
    Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.

  1. Remove the inverter cover. (Click here)

    NOTICE:
    1. Wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
    2. Prevent water in the reservoir tank from entering the inverter.
    3. Removing the inverter cover causes the MG ECU board to be exposed. Therefore, temporarily install the inverter cover for each area to be inspected.



    A103665E01

  1. Check the connections of the MG ECU connectors.

    OK:
    Connectors are connected securely and there is no poor connection.



NG
CONNECT SECURELY
OK


3.INSPECT HV RELAY ASSEMBLY (SMR2)

CAUTION:
Be sure to wear insulated gloves and protective goggles.

  1. Check that the service plug grip is removed.

  1. Remove the HV relay assembly from the vehicle. (Click here)



    A108055E07

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

Standard Resistance :
Tester Condition
Specified Condition
S47-1 - S44-1
Below 1 Ω
(Apply auxiliary battery voltage between terminals (CON2 (S48-1) and GND (S48-4))

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

    Standard Resistance :
    Tester Condition
    		Specified Condition
    CON2 (S48-1) - GND (S48-4)
    		20 to 60 Ω
    at -35 to 80°C ( -31 to 176°F)



NG
REPLACE HV RELAY ASSEMBLY
OK


4.INSPECT HV RELAY ASSEMBLY (SMR3)

CAUTION:
Be sure to wear insulated gloves.

  1. Check that the service plug grip is removed.



    A108054E04

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

Standard Resistance :
Tester Condition
Specified Condition
S49-1 - S45-1
Below 1 Ω
(Apply auxiliary battery voltage between terminals (CON3 (S48-2) and GND (S48-4))

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

Standard Resistance :
Tester Condition
Specified Condition
CON3 (S48-2) - GND (S48-4)
20 to 60 Ω
at -35 to 80°C ( -31 to 176°F)



NG
REPLACE HV RELAY ASSEMBLY
OK


5.CONFIRM INFORMATION (EXCLUSIVE INFO 4)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to the ON position and check for HV system DTC P0A0D-350 by following the prompts on the intelligent tester 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.

  1. Display freeze frame data corresponding to DTC P0A94 and select the information.

  1. Select INF code 556 and read "Exclusive Info 4".

    Result::
    Displayed item in exclusive information 4
    		Proceed to
    -63 to 64
    		A
    65 to 128
    		B



B
Go to step 8
A


6.CHECK HARNESS AND CONNECTOR (MG ECU - MOTOR RESOLVER)


    A103666E04

  1. Disconnect the I24 connector from the MG ECU.

  1. Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.

    Standard Voltage:
    Tester Connection
    		Specified Condition
    MRF (I24-13) - Body ground
    		Below 1 V
    MRFG (I24-23) - Body ground
    		Below 1 V
    MSN (I24-21) - Body ground
    		Below 1 V
    MSNG (I24-20) - Body ground
    		Below 1V
    MCS (I24-19) - Body ground
    		Below 1 V
    MCSG (I24-18) - Body ground
    		Below 1 V

  1. Turn the ignition switch off.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    MRF (I24-13) - MRFG (I24-23)
    		7.65 to 10.2 Ω
    MSN (I24-21) - MSNG (I24-20)
    		12.6 to 16.8 Ω
    MCS (I24-19) - MCSG (I24-18)
    		12.6 to 16.8 Ω

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    MRF (I24-13) or MRFG (I24-23) - Body ground
    		10 kΩ or higher
    MSN (I24-21) or MSNG (I24-20) - Body ground
    		10 kΩ or higher
    MCS (I24-19) or MCSG (I24-18) - Body ground
    		10 kΩ or higher



NG
Go to step 9
OK


7.CHECK HARNESS AND CONNECTOR (MG ECU -GENERATOR RESOLVER)


    A103666E03

  1. Disconnect the I24 connector from the MG ECU.

  1. Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.

    Standard Voltage:
    Tester Connection
    		Specified Condition
    GRF (I24-12) - Body ground
    		Below 1 V
    GRFG (I24-23) - Body ground
    		Below 1 V
    GSN (I24-11) - Body ground
    		Below 1 V
    GSNG (I24-10) - Body ground
    		Below 1V
    GCS (I24-9) - Body ground
    		Below 1 V
    GCSG (I24-8) - Body ground
    		Below 1 V

  1. Turn the ignition switch off.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    GRF (I24-12) - GRFG (I24-22)
    		7.65 to 10.2 Ω
    GSN (I24-11) - GSNG (I24-10)
    		12.6 to 16.8 Ω
    GCS (I24-9) - GCSG (I24-8)
    		12.6 to 16.8 Ω

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    GRF (I24-12) or GRFG (I24-22) - Body ground
    		10 kΩ or higher
    GSN (I24-11) or GSNG (I24-10) - Body ground
    		10 kΩ or higher
    GCS (I24-9) or GCSG (I24-8) - Body ground
    		10 kΩ or higher



NG
Go to step 10
OK

REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY 

8.CHECK HARNESS AND CONNECTOR (MG ECU - REAR MOTOR RESOLVER)


    A103667E04

  1. Disconnect the I25 connector from the MG ECU.

  1. Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.

    Standard Voltage:
    Tester Connection
    		Specified Condition
    RRF (I25-21) - Body ground
    		Below 1 V
    RRFG (I25-22) - Body ground
    		Below 1 V
    RSN (I25-29) - Body ground
    		Below 1 V
    RSNG (I25-30) - Body ground
    		Below 1V
    RCS (I25-11) - Body ground
    		Below 1 V
    RCSG (I25-23) - Body ground
    		Below 1 V

  1. Turn the ignition switch off.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    RRF (I25-21) - Body ground
    		7.65 to 10.2 Ω
    RSN (I25-29) - Body ground
    		12.6 to 16.8 Ω
    RCS (I25-11) - Body ground
    		12.6 to 16.8 Ω

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    RRF (I25-21) or RRFG (I25-22) - Body ground
    		10 kΩ or higher
    RSN (I25-29) or RSNG (I25-30) - Body ground
    		10 kΩ or higher
    RCS (I25-11) or RCSG (I25-23) - Body ground
    		10 kΩ or higher



NG
Go to step 11
OK

REPLACE REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY 

9.INSPECT MOTOR RESOLVER


    A083675E04

  1. Disconnect the M7 motor resolver connector.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    MRF (M7-1) - MRFG (M7-4)
    		7.65 to 10.2 Ω
    MSN (M7-2) - MSNG (M7-5)
    		12.6 to 16.8 Ω
    MCS (M7-3) - MCSG (M7-6)
    		12.6 to 16.8 Ω

  1. Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Specified Condition
    MRF (M7-1) - MSN (M7-2)
    		10 MΩ or higher
    MRF (M7-1) - MCS (M7-3)
    		10 MΩ or higher
    MSN (M7-2) - MCS (M7-3)
    		10 MΩ or higher
    MRFG (M7-4) - MSNG (M7-5)
    		10 MΩ or higher
    MRFG (M7-4) - MCSG (M7-6)
    		10 MΩ or higher
    MSNG (M7-5) - MCSG (M7-6)
    		10 MΩ or higher
    Each terminal listed above - transaxle housing
    		10 MΩ or higher



NG
REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR 

10.INSPECT GENERATOR RESOLVER

  1. Remove the w/ converter inverter assembly. (Click here)



    A105163E02

  1. Disconnect the M6 generator resolver connector.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    GRF (M6-1) - GRFG (M6-6)
    		7.65 to 10.2 Ω
    GSN (M6-2) - GSNG (M6-7)
    		12.6 to 16.8 Ω
    GCS (M6-3) - GCSG (M6-8)
    		12.6 to 16.8 Ω

  1. Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Specified Condition
    GRF (M6-1) - GSN (M6-2)
    		10 MΩ or higher
    GRF (M6-1) - GCS (M6-3)
    		10 MΩ or higher
    GSN (M6-2) - GCS (M6-3)
    		10 MΩ or higher
    GRFG (M6-6) - GSNG (M6-7)
    		10 MΩ or higher
    GRFG (M6-6) - GCSG (M6-8)
    		10 MΩ or higher
    GSNG (M6-7) - GCSG (M6-8)
    		10 MΩ or higher
    Each terminal listed above - transaxle housing
    		10 MΩ or higher



NG
REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR 

11.INSPECT REAR MOTOR RESOLVER


    A083675E05

  1. Disconnect the M11 rear motor resolver connector.

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

    Standard Resistance:
    Tester Connection
    		Specified Condition
    RRF (M11-1) - RRFG (M11-4)
    		7.65 to 10.2 Ω
    RSN (M11-2) - RSNG (M11-5)
    		12.6 to 16.8 Ω
    RCS (M11-3) - RCSG (M11-6)
    		12.6 to 16.8 Ω

  1. Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Specified Condition
    MRF (M11-1) - MSN (M11-2)
    		10 MΩ or higher
    RRF (M11-1) - RCS (M11-3)
    		10 MΩ or higher
    RSN (M11-2) - RCS (M11-3)
    		10 MΩ or higher
    RRFG (M11-4) - RSNG (M11-5)
    		10 MΩ or higher
    RRFG (M11-4) - RCSG (M11-6)
    		10 MΩ or higher
    RSNG (M11-5) - RCSG (M11-6)
    		10 MΩ or higher
    Each terminal listed above - transaxle housing
    		10 MΩ or higher



NG
REPLACE REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR