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 source voltage. The hybrid vehicle control ECU stops the compressor control and stores this DTC if 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 Open or short to ground in inverter control power voltage circuit

  • Compressor with motor assembly

  • CAN communication system

 Memorized

CAUTION / NOTICE / HINT

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.

  • 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 for both 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