HYBRID CONTROL SYSTEM, Diagnostic DTC:P0A94-587

DTC Code DTC Name
P0A94-587 DC / DC Converter Performance

DESCRIPTION

For a description of the boost converter, Click here.

The MG ECU uses a voltage sensor (VL) that is built into the boost converter to detect the high voltage before it is boosted. The ECU also uses the battery smart unit to detect HV battery voltage (VB).

Tech Tips

Using the intelligent tester, check the Data List of HV battery voltage and current. If these values are not within the below range, there is a battery smart unit malfunction.

A01NFZJE02
DTC No. INF Code DTC Detection Condition Trouble Area
P0A94 587 Voltages from HV battery voltage (VB) sensor and boost converter voltage (VL) sensor deviate

  • Inverter with converter assembly

  • Battery smart unit

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK DTC OUTPUT (HV)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Check if DTCs are output.

      Result
      Result Proceed to
      DTC P0A94-587 only is output. Alternatively, P0A94- 587 and any DTCs other than P0A1F-129, P0A94-442 or P0A94-585 are output. A
      P0A94-587 and P0A1F-129 (HV battery voltage circuit malfunction) are output. B
      P0A94-587 and P0A94-442 (abnormal voltage execution value) are output. C
      P0A94-587 and P0A94-585 (boost converter voltage (VL) sensor performance problem) are output. D

    5. Turn the power switch off.


    B

    GO TO DTC CHART Click here

    C

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    D

    GO TO DTC CHART Click here

    A

  2. CLEAR DTC


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Clear DTCs and freeze frame data.

    5. Turn the power switch off.


    NEXT

  3. CHECK DTC OUTPUT (HV)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (READY). (*1)

    3. Enter the following menus: Powertrain / Hybrid Control / Data List (*2)

    4. If both HV battery voltage (VB) and VL-Voltage before Boosting are less than 235 V, move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time to raise them to 235 V or more. (*3)

    5. Move the shift lever to the N position. (*4)

    6. Turn the A/C switch to the MAX COOL position. (*5)

    7. Confirm that "Batt Pack Current Val" is more than 3 A. (*6)

    8. Leave the vehicle for 15 seconds in steps (*4), (*5) and (*6) shown above. (*7)

    9. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes. (*8)

    10. Check if DTCs are output. (*9)

      Note

      If the low battery charge warning light comes on, move the shift lever to the P position and start the engine to charge the HV battery. After the engine stops, perform steps (*1) through (*9) again.

      Result
      Result Proceed to
      No DTCs are output. A
      P0A1F-129 (HV battery voltage circuit malfunction) is output. B
      P0A94-585 (boost converter voltage (VL) sensor performance problem) is output. C
      P3000-388 (discharge inhibition) is output. D
      P3004-132 (high voltage power supply line problem) is output. E

    11. Turn the power switch off.


    B

    REPLACE BATTERY SMART UNIT Click here

    C

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    D

    LEAVE VEHICLE IN P POSITION, AND CHARGE HV BATTERY IN IDLE STATUS UNTIL IDLING STOPS

    E

    REPLACE BATTERY SMART UNIT Click here

    A

  4. CHECK DTC OUTPUT (HV)


    1. Perform a road test that repeats full acceleration to 37 mph (60 km/h) and then braking to a complete stop three times. (*10)

    2. Connect the intelligent tester to the DLC3.

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes. (*11)

    4. Check if DTCs are output. (*12)

      Result
      Result Proceed to
      No DTCs are output. A
      P0A1F-129 (HV battery voltage circuit malfunction) is output. B
      P0A94-585 (boost converter voltage (VL)) sensor performance problem) is output. C
      P3000-388 (discharge inhibition) is output. D
      P3004-132 (high voltage power supply line problem) is output. E

    5. Turn the power switch off.


    B

    REPLACE BATTERY SMART UNIT Click here

    C

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    D

    LEAVE VEHICLE IN P POSITION, AND CHARGE HV BATTERY IN IDLE STATUS UNTIL IDLING STOPS (PERFORM STEPS (*10) THROUGH (*12))

    E

    REPLACE BATTERY SMART UNIT Click here

    A

  5. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (READY).

    3. Enter the following menus: Powertrain / Hybrid Control / Data List

    4. Select HV battery voltage (VB) , VL-Voltage before Boosting and VH-Voltage after Boosting in the Data List.

    5. If both HV battery voltage (VB) and VL-Voltage before Boosting are less than 235 V, move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time to raise them to 235 V or more.

    6. Turn the engine off, move the shift lever to the N position, and read the Data List when the vehicle is stationary.

      Result
      Result Proceed to
      Both of the following are not satisfied. A

      Both of the following are satisfied:


      • Difference between "Power Resource VB" and "VH-Voltage after Boosting" is less than 5 V.

      • Difference between VL-Voltage before Boosting and "VH-Voltage after Boosting" is more than 30 V.

      		 B

      Both of the following are satisfied:


      • Difference between "VH-Voltage after Boosting" and "VL-Voltage before Boosting" is more than 5 V.

      • Difference between "Power Resource VB" and "VH-Voltage after Boosting" is less than 18 V.

      		 C

    7. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    C

    REPLACE BATTERY SMART UNIT Click here

    A

  6. CHECK FREEZE FRAME DATA


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Read the freeze frame data of DTC P0A94-587.

      Result
      Result Proceed to
      Both of the following are satisfied or both of the following are not satisfied. A
      "Power Resource VB" is less than 235 V or more than 395 V. B
      "VL-Voltage before Boosting" is less than 235 V or more than 395 V. C

    5. Turn the power switch off.


    B

    REPLACE BATTERY SMART UNIT Click here

    C

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    A

  7. CHECK FREEZE FRAME DATA


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Read the freeze frame data of DTC P0A94-587.

      Tech Tips

      In the freeze frame data, read the HV battery voltage value and all of the battery block voltage values.

      Result
      Result Proceed to
      Others (Freeze frame data is not stored). A

      Both of the following are satisfied:


      • Sum of all "Battery Block" voltage is more than (HV battery voltage - 55 V)

      • Sum of all "Battery Block" voltage is less than (HV battery voltage + 35 V)

      		 B
      Neither A nor B is satisfied. C

    5. Turn the power switch off.


    B

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

    C

    REPLACE BATTERY SMART UNIT Click here

    A

  8. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Data List

    4. If both HV battery voltage (VB) and VL-Voltage before Boosting are less than 235 V, move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time to raise them to 235 V or more.

    5. Turn the engine off, move the shift lever to the N position, and read the Data List of all battery block and HV battery voltages, when the vehicle is stationary.

      Result
      Result Proceed to

      Both of the following are satisfied:


      • Sum of all "Battery Block" voltage is more than (HV battery voltage -55 V)

      • Sum of all "Battery Block" voltage is less than (HV battery voltage +35 V)

      		 A
      The preceding condition is not satisfied. B

    6. Turn the power switch off.


    B

    REPLACE BATTERY SMART UNIT Click here

    A

    REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here