HYBRID BATTERY SYSTEM, Diagnostic DTC:P0A99-123

DTC Code DTC Name
P0A99-123 Hybrid Battery Pack Cooling Fan 2 Control Circuit Low

DESCRIPTION

The speed of the battery cooling blower assembly (for lower side) is controlled by the hybrid vehicle control ECU in accordance with the HV battery temperature and SOC. Battery cooling blower assembly (for lower side) power is supplied when the FCTL terminal of the hybrid vehicle control ECU turns on the BATT FAN 1 relay. The hybrid vehicle control ECU sends command signals (SI1) to the battery cooling blower assembly (for lower side) to achieve the fan speed that corresponds to the HV battery temperature. Voltage (VM1) from the battery cooling blower assembly (for lower side) is used to monitor the operation of the battery cooling blower assembly (for lower side). The voltage is sent from the battery cooling blower assembly (for lower side) to the hybrid vehicle control ECU via the battery smart unit. Between the battery smart unit and the hybrid vehicle control ECU, serial communication is used.

A01H1B1E03
DTC Code DTC Detection Condition Trouble Area
P0A99-123 The output voltage of the battery cooling blower assembly (for lower side) (VM1) is lower than the target control voltage range when the battery cooling blower assembly (for lower side) is activated. (1 trip detection)

  • Harness or connector

  • BATT FAN 1 fuse

  • B-FAN RLY fuse

  • Luggage room junction block (BATT FAN 1 relay)

  • Battery cooling blower assembly (for lower side)

  • Battery smart unit

  • Hybrid vehicle control ECU

WIRING DIAGRAM

A01GYDZE02

CAUTION:


  • Before inspecting the high-voltage system, 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.

Tech Tips

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR DTCS (DTC P0AFC-123 IS OUTPUT)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.

    4. Check if DTCs are output.

      Result
      Result Proceed to
      P0AFC-123 is not output. A
      P0AFC-123 is output. B

    B

    GO TO DTC (P0AFC-123) Click here

    A

  2. CHECK FUSES (BATT FAN 1 AND B-FAN RLY)


    1. A01H03OE01

      Turn the power switch off.

    2. Remove the BATT FAN 1 fuse and B-FAN RLY fuse from the luggage room junction block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      BATT FAN 1 fuse Always Below 1 Ω
      B-FAN RLY fuse Always Below 1 Ω

    NG

    REPLACE FUSE (BATT FAN 1 OR B-FAN RLY)

    OK

  3. CHECK HARNESS AND CONNECTOR (NO. 1 BATTERY PACK WIRE CONNECTOR [B SIDE] - BATTERY)


    1. A01H1QFE05

      Install the BATT FAN 1 fuse and B-FAN RLY fuse.

    2. Turn the power switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      zR3-9 (IG1) - Body ground Power switch on (IG) 11 to 14 V

      Tech Tips


      • For the removal and installation procedures related to the No. 1 battery pack wire connector inspection, Click here.

      • Perform this inspection with the No. 1 battery pack wire connector connected.


    NG

    Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (NO. 1 BATTERY PACK WIRE CONNECTOR [A SIDE] - HYBRID VEHICLE CONTROL ECU)


    1. Disconnect the zR3 No. 1 battery pack wire connector.

      A01GZLJE11

      Tech Tips

      For the removal and installation procedures related to the No. 1 battery pack wire connector inspection, Click here.

    2. Disconnect the A77 hybrid vehicle control ECU connector.

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

      Standard Resistance (Check for open)
      Tester Connection Switch Condition Specified Condition
      zR3-17 (SI1) - A77-35 (SI1) Power switch off Below 1 Ω
      zR3-18 (GND1) - Body ground Power switch off Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Switch Condition Specified Condition
      zR3-17 (SI1) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Turn the power switch on (IG).

    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage (Check for +B short)
      Tester Connection Switch Condition Specified Condition
      zR3-17 (SI1) - Body ground Power switch on (IG) Below 1 V

      Tech Tips

      If the power switch is turned on (IG) under the conditions above, DTCs may be stored. In this case, use the intelligent tester to clear the DTCs Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (NO. 1 BATTERY PACK WIRE CONNECTOR [B SIDE] - BATTERY COOLING BLOWER [FOR LOWER SIDE])

    CAUTION:

    Be sure to wear insulated gloves.


    1. A01GZ57E04

      Remove the HV battery Click here.

    2. Disconnect the z77 battery cooling blower assembly (for lower side) connector.

      Tech Tips

      For the removal and installation procedures related to the battery cooling blower assembly (for lower side) connector inspection, Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      zR3-17 (SI1) - z77-3 (SI1) Always Below 1 Ω
      zR3-18 (GND1) - z77-4 (GND1) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (NO. 1 BATTERY PACK WIRE CONNECTOR [B SIDE] - BATTERY COOLING BLOWER [FOR LOWER SIDE])

    CAUTION:

    Be sure to wear insulated gloves.


    1. A01GZ57E07

      Disconnect the z77 battery cooling blower assembly (for lower side) connector.

      Tech Tips

      For the removal and installation procedures related to the battery cooling blower assembly (for lower side) connector inspection, Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      zR3-9 (IG1) - z77-1 (IG1) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK HARNESS AND CONNECTOR (BATTERY COOLING BLOWER [FOR LOWER SIDE] - BATTERY SMART UNIT)

    CAUTION:

    Be sure to wear insulated gloves.


    1. A01GXHNE02

      Disconnect the z77 battery cooling blower assembly (for lower side) connector.

      Tech Tips

      For the removal and installation procedures related to the battery cooling blower assembly (for lower side) connector inspection, Click here.

    2. Disconnect the z36 battery smart unit connector.

      Tech Tips

      For the removal and installation procedures related to the battery smart unit connector inspection, Click here.

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

      Standard Resistance (Check for open)
      Tester Connection Condition Specified Condition
      z77-2 (VM1) - z36-7 (VM1) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      z77-2 (VM1) - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK BATTERY COOLING BLOWER ASSEMBLY (for Lower Side) (VM1 VOLTAGE)

    CAUTION:

    Be sure to wear insulated gloves.


    1. A01H0BTE01

      Place the HV battery in the vehicle so that measurements can be made at the battery cooling blower assembly (for lower side) connector.

      Note

      Make sure all the covers are installed to the HV battery when placing it in the vehicle, and then remove the covers again after the HV battery is in place.

      Tech Tips


      • Follow the installation procedures to the point where the HV battery is set in the vehicle Click here.

      • Do not install the service plug grip.

    2. Reconnect all the connectors that were disconnected when the HV battery was removed.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the power switch on (IG).

    5. Select the following menu items: Powertrain / Hybrid Control / Data List / VMF Fan Motor Voltage 2.

    6. Using a service wire, connect terminals z77-3 (SI1) and z77-4 (GND1) of the battery cooling blower assembly (for lower side) connector.

      CAUTION:

      Do not touch the fan while it is operating.

    7. While the battery cooling blower assembly (for lower side) is operating, compare the value in the data list ("VMF Fan Motor Voltage 2") with the voltage value that was actually measured at the battery cooling blower assembly (for lower side) connector.

      Result
      Tester Connection Switch Condition Result Proceed to
      z77-2 (VM1) - z77-4 (GND1) Power switch on (IG) The difference between the value in the Data List ("VMF Fan Motor Voltage 2") and the actual measurement value is 1 V or higher. A
      The difference between the value in the Data List ("VMF Fan Motor Voltage 2") and the actual measurement value is below 1 V and the value in the Data List ("VMF Fan Motor Voltage 2") is 0.6 V or less. B
      The difference between the value in the Data List ("VMF Fan Motor Voltage 1") and the actual measurement value is below 1 V and the value in the Data List ("VMF Fan Motor Voltage 2") is higher than 0.6 V. C

      Tech Tips


      • Perform this inspection with the battery cooling blower assembly (for lower side) connector connected.

      • If the power switch is turned on (IG) with the service plug grip removed, DTC P0A0D-350 for the interlock switch system will be set. If this DTC is output, clear the DTC using the intelligent tester Click here.


    B

    REPLACE BATTERY COOLING BLOWER ASSEMBLY (for Lower Side) Click here

    C

    REPLACE HYBRID VEHICLE CONTROL ECU Click here

    A

    REPLACE BATTERY SMART UNIT Click here

  9. INSPECT LUGGAGE ROOM JUNCTION BLOCK (BATT FAN 1 RELAY)


    1. Install the BATT FAN 1 fuse and B-FAN RLY fuse.

      A01GZX6E02

    2. Remove the luggage room junction block.

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

      Tech Tips

      The BATT FAN 1 relay is located inside the luggage room junction block.

      Standard Resistance
      Tester Connection Condition Specified Condition
      LG-1 - LD-3 Battery voltage is not applied between terminals LH-1 and LD-14. 10 kΩ or higher
      LG-1 - LD-3 Battery voltage is applied between terminals LH-1 and LD-14. Below 1 Ω

    NG

    REPLACE LUGGAGE ROOM JUNCTION BLOCK (BATT FAN 1 RELAY)

    OK

  10. CHECK HARNESS AND CONNECTOR (LUGGAGE ROOM JUNCTION BLOCK - HYBRID VEHICLE CONTROL ECU)


    1. A01GXNLE04

      Disconnect the A77 hybrid vehicle control ECU connector.

    2. Disconnect the LD luggage room junction block connector.

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

      Standard Resistance (Check for open)
      Tester Connection Switch Condition Specified Condition
      LD-14 - A77-26 (FCTL) Power switch off Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Switch Condition Specified Condition
      LD-14 or A77-26 (FCTL) - Body ground and other terminals Power switch off 10 kΩ or higher

      Note

      When taking measurements with an electrical tester, do not apply excessive force to the tester probes to avoid damaging the terminals.

    4. Turn the power switch on (IG).

    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage (Check for +B short)
      Tester Connection Switch Condition Specified Condition
      A77-26 (FCTL) - Body ground Power switch on (IG) Below 1 V

      Tech Tips

      If the power switch is turned on (IG) under the conditions above, DTCs may be stored. In this case, use the intelligent tester to clear the DTCs Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. CHECK HARNESS AND CONNECTOR (LUGGAGE ROOM JUNCTION BLOCK - NO. 1 BATTERY PACK WIRE CONNECTOR [A SIDE])


    1. Disconnect the zR3 No. 1 battery pack wire connector.

      A01GZS5E02

    2. Disconnect the LD luggage room junction block connector.

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

      Standard Resistance (Check for open)
      Tester Connection Switch Condition Specified Condition
      LD-3 - zR3-9 (IG1) Power switch off Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Switch Condition Specified Condition
      LD-3 or zR3-9 (IG1) - Body ground and other terminals Power switch off 10 kΩ or higher

      Note

      When taking measurements with an electrical tester, do not apply excessive force to the tester probes to avoid damaging the terminals.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE HYBRID VEHICLE CONTROL ECU Click here