AIR CONDITIONING SYSTEM, Diagnostic DTC:B1471/71

DTC Code DTC Name
B1471/71 A/C Inverter High Voltage Power Resource System Malfunction

DESCRIPTION

The air conditioning inverter assembly monitors power voltage from the main battery in the circuit. It stops compressor control and outputs the DTC when the monitored voltage is outside the specified range.

The output DTC is memorized as a past DTC. Compressor control may not resume unless the power switch is turned off.

DTC No. DTC Detection Condition Trouble Area
B1471/71

  • Open or short in air conditioning inverter high voltage power resource system

  • Boost pressure system is broken or malfunctioning

  • Heater wire

  • Compressor with motor assembly

  • Hybrid control system

  • Inverter with converter assembly

  • Electric vehicle fuse

  • CAN communication system

WIRING DIAGRAM

A000Z3DE02

CAUTION / NOTICE / HINT

CAUTION:


  • When troubleshooting B1471/71, be sure to wrap tools with electrical tape. (It is very dangerous if high voltage is shorted to ground through tools.)

  • Wear electrically insulated gloves and pull out the service plug grip before inspection as procedures may require disconnecting high-voltage connectors. Be sure to carry the removed service plug grip because other workers may install it by mistake.

  • Be sure to carry the removed service plug grip because other workers may install it by mistake.

  • Do not touch the high-voltage connectors or terminals for 10 minutes after the service plug grip is removed.

Note

The hybrid control system and air conditioning system output DTCs separately. Inspect DTCs following the flowchart for the hybrid control system first if any DTCs from those systems are output simultaneously.

Tech Tips


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

  • When measuring insulation resistance using a megohmmeter, measure the resistance while jiggling the high-voltage wire harness.

  • When measuring insulation resistance using a megohmmeter, set the megohmmeter to 500 V.

PROCEDURE


  1. CHECK DTC (HYBRID CONTROL SYSTEM)


    1. Check if DTCs for the hybrid control system are output using the intelligent tester Click here.

      Result
      Result Proceed to
      Hybrid control system DTC is not output A
      Hybrid control system DTC is output B

    B

    GO TO HYBRID CONTROL SYSTEM Click here

    A

  2. CHECK DTC (CAN COMMUNICATION SYSTEM)


    1. Check if DTCs for the CAN communication system are output using the intelligent tester.


      Result
      Result Proceed to
      CAN DTC is not output A
      CAN DTC is output (for LHD) B
      CAN DTC is output (for RHD) C

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  3. INSPECT INVERTER WITH CONVERTER ASSEMBLY (ELECTRIC VEHICLE FUSE)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Turn the power switch off.

    2. Remove the service plug grip. Click here

      Note

      After removing the service plug grip, do not turn the power switch on (READY) unless instructed by the repair manual because this may cause a malfunction.

    3. Remove the inverter terminal cover from the inverter with converter assembly.


      Note

      Lift the inverter terminal cover horizontally so that it does not tilt. Failure to do so may break the inverter cover guide pins.

      A000TY6E01
      *1 for LHD:
      *2 for RHD:

    4. Disconnect the motor cable and generator cable from the inverter with converter assembly.

      A000Z8GE01
      *1 for LHD:
      *2 for RHD:

    5. Remove the connector cover from the inverter with converter assembly.


      A000YZ3E01
      *1 for LHD:
      *2 for RHD:

      Tech Tips

      Make sure that no foreign objects have entered or contaminated the inverter with converter assembly.

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

      A000UOHE02
      *1 for LHD:
      *2 for RHD:
      *3 Electric Vehicle Fuse

      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
      Tester Connection Switch Condition Specified Condition
      Electric vehicle fuse - Body ground Power switch off 1.0 MΩ or higher
      Result
      Result Proceed to
      OK A
      NG (for LHD) B
      NG (for RHD) C

    B

    REPLACE ELECTRIC VEHICLE FUSE Click here

    C

    REPLACE ELECTRIC VEHICLE FUSE Click here

    A

  4. INSPECT HEATER WIRE


    1. A000YPSE01
      *1 Front view of wire harness connector: (to Compressor with Motor Assembly)
      *2 Front view of wire harness connector: (to Inverter with Converter Assembly)

      Disconnect the k2 and j1 heater wire connectors.

      CAUTION:

      Be sure to wear insulated gloves.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      k2-1 (PE) - j1-1 (ACPE) Always Below 1 Ω
      k2-2 (PB) - j1-2 (ACPB)
      k2-1 (PE) - k2-2 (PB) Always 10 kΩ or higher

    OK

    REPLACE COMPRESSOR WITH MOTOR ASSEMBLY Click here

    NG

    REPLACE HEATER WIRE Click here