AIR CONDITIONING SYSTEM, Diagnostic DTC:B1497

DTC Code DTC Name
B1497 Communication Malfunction (Bus Ic)

DESCRIPTION

The air conditioning harness assembly connects the air conditioning amplifier assembly and the servo motors. The air conditioning amplifier assembly supplies power and sends operation instructions to each servo motor through the air conditioning harness assembly. Each servo motor sends damper position information to the air conditioning amplifier assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1497 Communication Malfunction (Bus Ic)

  • Diagnosis condition: None

  • Malfunction status: Error or open in communication line between air conditioning amplifier assembly and servo motor

  • Air conditioning harness assembly

  • No. 1 air conditioning radiator damper servo sub-assembly

  • No. 2 air conditioning radiator damper servo sub-assembly

  • No. 3 air conditioning radiator damper servo sub-assembly

  • No. 4 air conditioning radiator damper servo sub-assembly

  • No. 1 blower damper servo sub-assembly

  • Air conditioning amplifier assembly

 Memorized

WIRING DIAGRAM

Figure 1. for LHD:

B000NWCE02

Figure 2. for RHD:

B000NWCE03

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (SERVO PULSE)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Air Conditioner / Active Test.

    5. Check the operation by referring to the table below.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Mix Servo Targ Pulse(D)

        for LHD:

      • No. 1 air conditioning radiator damper servo sub-assembly (driver side upper air mix) operation


        for RHD:

      • No. 4 air conditioning radiator damper servo sub-assembly (driver side upper air mix) operation

      Min.: 128

      Max.: 383

      		 Operates between 186 and 258 pulses
      Air Mix Servo Targ Pulse(P) No. 2 air conditioning radiator damper servo sub-assembly (front passenger side upper air mix) operation

      Min.: 128

      Max.: 383

      		 Operates between 154 and 258 pulses
      Air Inlet Damper Targ Pulse No. 1 blower damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 206 and 238 pulses
      Cool A/M Servo Pulse(D)

        for LHD:

      • No. 1 air conditioning radiator damper servo sub-assembly (driver side lower air mix) operation


        for RHD:

      • No. 4 air conditioning radiator damper servo sub-assembly (driver side lower air mix) operation

      Min.: 128

      Max.: 383

      		 Operates between 154 and 258 pulses
      Cool A/M Servo Pulse(P) No. 2 air conditioning radiator damper servo sub-assembly (front passenger side lower air mix) operation

      Min.: 128

      Max.: 383

      		 Operates between 254 and 326 pulses
      Face A/O Servo Pulse(D)

        for LHD:

      • No. 3 air conditioning radiator damper servo sub-assembly (MODE FACE) operation


        for RHD:

      • No. 1 air conditioning radiator damper servo sub-assembly (MODE FACE) operation

      Min.: 128

      Max.: 383

      		 Operates between 258 and 364 pulses
      Foot A/O Servo Pulse(D)

        for LHD:

      • No. 3 air conditioning radiator damper servo sub-assembly (MODE FOOT) operation


        for RHD:

      • No. 1 air conditioning radiator damper servo sub-assembly (MODE FOOT) operation

      Min.: 128

      Max.: 383

      		 Operates between 256 and 365 pulses
      DEF A/O Servo Pulse(D)

        for LHD:

      • No. 4 air conditioning radiator damper servo sub-assembly (MODE DEF) operation


        for RHD:

      • No. 3 air conditioning radiator damper servo sub-assembly (MODE DEF) operation

      Min.: 128

      Max.: 383

      		 Operates between 164 and 270 pulses

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Mix Servo Targ Pulse(D)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Mix Servo Targ Pulse(P)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Air Inlet Damper Targ Pulse

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Cool A/M Servo Pulse(D)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Cool A/M Servo Pulse(P)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Face A/O Servo Pulse(D)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Foot A/O Servo Pulse(D)

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      DEF A/O Servo Pulse(D)
      OK
      Damper servo motor is operated.

    6. Check the operation by referring to the table below.

      Result
      Result Proceed to
      All damper servo motors are not operated A
      Any damper servo motor is not operated B
      All damper servo motors are operated C

    B

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

  2. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (POWER SOURCE CIRCUIT)


    1. Disconnect the air conditioning amplifier assembly connector.

      B000RYKC01
      *a

      Component without harness connected

      (Air Conditioning Amplifier Assembly)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (BUS G) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      2 (BUS G) - 3 (BUS) Power switch off 11 to 14 V

    4. Using an oscilloscope, check the waveform.

      Item Content
      Tester Connection 2 (BUS G) - 3 (BUS)
      Tool Setting 2 V/DIV., 20 μs/DIV.
      Condition Power switch on (IG)
      OK
      The waveform displays properly.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here