AIR CONDITIONING SYSTEM, Diagnostic DTC:B1497/97

DTC Code DTC Name
B1497/97 BUS IC Communication Malfunction

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
B1497/97 BUS IC Communication Malfunction Error or open in communication line

  • 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

  • Air conditioning amplifier assembly

Memorized

(10 sec. or more)*

WIRING DIAGRAM


  1. for Dual Type

    A003K8AE04

  2. for Single Type

    A003P1EE05

PROCEDURE


  1. CONFIRM MODEL


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      for LHD A
      for RHD B

    B

    PERFORM ACTIVE TEST USING GTS Click here

    A

  2. PERFORM ACTIVE TEST USING GTS


    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. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Mix Servo Targ Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix*1 or air mix*2) pulse

      Min.: 128

      Max.: 383

      		 Operates between 165 to 257 pulses
      Air Outlet Servo Pulse (D) No. 1 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 164 to 256 pulses
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

      • *1: for Dual Type

      • *2: for Single Type


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

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

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      Each damper servo motor operates smoothly.
      Result
      Result Proceed to
      All of the damper servo motors are malfunctioning A
      Any of the damper servo motors is normal B

    B

    PERFORM ACTIVE TEST USING GTS Click here

    A

  3. PERFORM ACTIVE TEST USING GTS


    1. Disconnect the No. 2 air conditioning radiator damper servo sub-assembly connector.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Air Conditioner / Active test.

    6. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      The damper servo motor operates smoothly.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY Click here

    NG

  4. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

    A003KR3C02
    *a

    Component with harness connected

    (Air Conditioning Amplifier Assembly)

    Note

    When inspecting the air conditioning amplifier assembly, do not bring the tester probes too close to each other as a short circuit may occur.


    1. Disconnect the z1 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z1-2 (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 Condition Specified Condition
      z1-4 (B BUS) - Body ground Power switch on (IG) 11 to 14 V

    4. Turn the power switch on (IG).

    5. Connect an oscilloscope to terminals z1-2 (BUS G) and z1-3 (BUS) of the air conditioning amplifier assembly and check the waveform.

      OK
      Waveform is similar to that shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

      Item Content
      Tool Setting 2 V/DIV., 2 ms./DIV.
      Condition Power switch on (IG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  5. PERFORM ACTIVE TEST USING GTS


    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. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Mix Servo Targ Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix*1 or air mix*2) pulse

      Min.: 128

      Max.: 383

      		 Operates between 165 to 257 pulses
      Air Outlet Servo Pulse (D) No. 1 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 164 to 256 pulses
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

      • *1: for Dual Type

      • *2: for Single Type


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

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

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      Each damper servo motor operates smoothly.
      Result
      Result Proceed to
      Only the No. 2 air conditioning radiator damper servo sub-assembly does not operate A
      Only the No. 1 air conditioning radiator damper servo sub-assembly does not operate B
      Only the No. 3 air conditioning radiator damper servo sub-assembly does not operate
      Only the No. 1 air conditioning radiator damper servo sub-assembly operates

    B

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    A

  6. INSPECT AIR CONDITIONING HARNESS ASSEMBLY (AIR CONDITIONING AMPLIFIER ASSEMBLY - NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY)


    1. Disconnect the z1 air conditioning amplifier assembly connector.

    2. Disconnect the No. 2 air conditioning radiator damper servo sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z1-2 (BUS G) - 3 (GND) Always Below 1 Ω
      z1-3 (BUS) - 1 (+B) Always Below 1 Ω
      z1-4 (B BUS) - 2 (LIN) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

  7. PERFORM ACTIVE TEST USING GTS


    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. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Mix Servo Targ Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) pulse

      Min.: 128

      Max.: 383

      		 Operates between 255 to 347 pulses
      Air Outlet Servo Pulse (P) No. 1 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 164 to 256 pulses
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

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

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

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      Each damper servo motor operates smoothly.
      Result
      Result Proceed to
      All of the damper servo motors are malfunctioning A
      Any of the damper servo motors is normal B

    B

    PERFORM ACTIVE TEST USING GTS Click here

    A

  8. PERFORM ACTIVE TEST USING GTS


    1. Disconnect the No. 2 air conditioning radiator damper servo sub-assembly connector.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Air Conditioner / Active test.

    6. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      The damper servo motor operates smoothly.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY Click here

    NG

  9. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

    A003KR3C02
    *a

    Component with harness connected

    (Air Conditioning Amplifier Assembly)

    Note

    When inspecting the air conditioning amplifier assembly, do not bring the tester probes too close to each other as a short circuit may occur.


    1. Disconnect the z1 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z1-2 (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 Condition Specified Condition
      z1-4 (B BUS) - Body ground Power switch on (IG) 11 to 14 V

    4. Turn the power switch on (IG).

    5. Connect an oscilloscope to terminals z1-2 (BUS G) and z1-3 (BUS) of the air conditioning amplifier assembly and check the waveform.

      OK
      Waveform is similar to that shown in the illustration.

      Tech Tips

      The waveform varies with the blower speed.

      Item Content
      Tool Setting 2 V/DIV., 2 ms./DIV.
      Condition Power switch on (IG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  10. PERFORM ACTIVE TEST USING GTS


    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. Perform the Active Test according to the display on the GTS.


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Air Mix Servo Targ Pulse(D) No. 2 air conditioning radiator damper servo sub-assembly (driver side air mix) pulse

      Min.: 128

      Max.: 383

      		 Operates between 255 to 347 pulses
      Air Outlet Servo Pulse (P) No. 1 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 164 to 256 pulses
      A/O Servo Pulse(Rr D) No. 3 air conditioning radiator damper servo sub-assembly pulse

      Min.: 128

      Max.: 383

      		 Operates between 250 to 297 pulses

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

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

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      A/O Servo Pulse(Rr D)
      OK
      Each damper servo motor operates smoothly.
      Result
      Result Proceed to
      Only the No. 2 air conditioning radiator damper servo sub-assembly does not operate A
      Only the No. 1 air conditioning radiator damper servo sub-assembly does not operate B
      Only the No. 3 air conditioning radiator damper servo sub-assembly does not operate
      Only the No. 1 air conditioning radiator damper servo sub-assembly operates

    B

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here

    A

  11. INSPECT AIR CONDITIONING HARNESS ASSEMBLY (AIR CONDITIONING AMPLIFIER ASSEMBLY - NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY)


    1. Disconnect the z1 air conditioning amplifier assembly connector.

    2. Disconnect the No. 2 air conditioning radiator damper servo sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z1-2 (BUS G) - 3 (GND) Always Below 1 Ω
      z1-3 (BUS) - 1 (+B) Always Below 1 Ω
      z1-4 (B BUS) - 2 (LIN) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 2 AIR CONDITIONING RADIATOR DAMPER SERVO SUB-ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here