AIR CONDITIONING SYSTEM, Diagnostic DTC:B1477/77

DTC Code DTC Name
B1477/77 A/C Inverter Low Voltage Power Resource System Malfunction

DESCRIPTION

The compressor with motor assembly monitors the inverter control power voltage in the circuit. The power management control ECU stops the compressor control and stores this DTC when the monitored voltage is outside the specified range.

This DTC will be stored as a history DTC. Compressor control may not resume unless the power switch is turned off.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1477/77 A/C Inverter Low Voltage Power Resource System Malfunction An open or short to ground in the inverter control power voltage circuit

  • Compressor with motor assembly

  • CAN communication system

 Memorized

CAUTION / NOTICE / HINT

CAUTION:


  • Wear insulated gloves and pull out the service plug grip before inspection as procedures may require disconnecting high-voltage connectors. Carry the removed service plug in your pocket to prevent other technicians from accidentally reconnecting it while you are servicing the vehicle.

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

Note


  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

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  • The hybrid control system and air conditioning system output DTCs separately. Perform troubleshooting for the hybrid control system first if DTCs from these systems are output simultaneously.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Using the GTS, check if the CAN communication system is functioning normally.

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      Result
      Result Proceed to
      CAN communication system DTCs are not output A
      CAN communication system DTCs are output B

    A

    REPLACE COMPRESSOR WITH MOTOR ASSEMBLY Click here

    B

    GO TO CAN COMMUNICATION SYSTEM Click here