DTC    B1476/76    A/C Inverter Load System Malfunction

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DESCRIPTION

The w/ motor compressor assembly stops compressor control and outputs DTC if the rotation load is too great or too small while controlling motor rotation in the w/ motor compressor assembly.
Possible causes are refrigerant gas leakage, overcharged refrigerant gas, insufficient cooling because of a condenser fan circuit malfunction, or compressor lock.

DTC No.
DTC Detecting Condition
Trouble Area
B1476/76
Motor's rotation load while the compressor is operating is too great or too small.
  1. Refrigerant volume
  1. w/ Motor compressor assembly
  1. Cooling fan system
  1. SFI system

WIRING DIAGRAM


E109280E03


INSPECTION PROCEDURE

1.PERFORM ACTIVE TEST BY INTELLIGENT TESTER
  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch ON and the intelligent tester main switch on.

  1. Select the item below in the ACTIVE TEST and then check that the fan operates.


ACTIVE TEST / AIR CONDITIONER 
Item
Test Details/Display
(Range)
Diagnostic Note
ELECTRICAL FAN
Electrical fan / OFF, ON
-

OK:
Electrical fan operates smoothly.



NG
GO TO COOLING SYSTEM
OK


2.CHECK DIAGNOSTIC TROUBLE CODE
  1. Check if DTCs for the SFI system are output using the intelligent tester.

OK:
DTCs are not output in the SFI system.



NG
GO TO SFI SYSTEM
OK


3.CHECK REFRIGERANT VOLUME


  1. Check the sight glass on the liquid tube.



      E108160E02
    1. LHD:



    2. E110731E01
    3. RHD:

  1. Prepare the vehicle according to the table below.
    Item
    Condition
    Vehicle door
    All fully open
    Temperature setting
    MAX. COLD
    Blower speed
    HI
    A/C
    ON
    Ignition switch
    ON

  1. Compare the sight glass to the following chart.

    Item
    Symptom
    Amount of refrigerant
    Corrective Actions
    1
    Bubbles exist
    Insufficient*
    1. Check for gas leakage and repair if necessary.
    2. Add refrigerant until bubbles disappear
    2
    No bubbles exist
    Empty, insufficient or excessive
    Refer to 3 and 4
    3
    No temperature difference between compressor inlet and outlet
    Empty or nearly empty
    1. Check for gas leakage with gas leak detector and repair if necessary.
    2. Evacuate the A/C system and recharge the proper amount of refrigerant.
    4
    Considerable temperature difference between compressor inlet and outlet
    Proper or excessive
    Refer to 5 and 6
    5
    Immediately after air conditioning is turned off, refrigerant clears
    Excessive
    1. Discharge refrigerant.
    2. Evacuate the A/C system and recharge the proper amount of refrigerant.
    6
    Immediately after air conditioning is turned off, refrigerant foams and then becomes clear
    Proper
    -

*: Bubbles in the sight glass with the vehicle's interior above 35°C (95°F) can be considered normal if cooling is sufficient.

NOTICE:
  1. If the amount of refrigerant is low, the compressor may stop in approximately 1 minute.
  2. If the compressor stops because of any trouble in the w/ motor compressor assembly, inspection may not be possible. For such cases, the w/ motor compressor assembly should be replaced.

OK:
Immediately after air conditioning is turned off, refrigerant foams and then becomes clear.



NG
CHARGE REFRIGERANT
OK

REPLACE W/MOTOR COMPRESSOR ASSEMBLY