AIR CONDITIONING SYSTEM(for Automatic 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 each servo motor. 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 the damper position information to the air conditioning amplifier assembly.

DTC Code

DTC Detection Condition

Trouble Area

B1497/97

An open circuit or malfunction in the communication line.

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

  • Air mix control servo motor LH

  • Air outlet control servo motor

  • Damper servo sub-assembly

  • Air mix control servo motor RH

  • Harness or connector

WIRING DIAGRAM

E235674E37

CAUTION / NOTICE / HINT

Note:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER

    1. Select the Active Test, using the intelligent tester to generate a control command, and then check that the servo motor operates.

      Table 1. Air Conditioner

      Tester Display

      Test Part

      Control Range

      Diagnostic Note

      Air Mix Servo Targ Pulse (D)

      Air mix control servo motor (for driver side) pulse

      Min.: 0, Max.: 255

      -

      Air Mix Servo Targ Pulse (P)

      Air mix control servo motor (for front passenger side) pulse

      Min.: 0, Max.: 255

      -

      Air Outlet Servo Pulse (D)

      Air outlet control servo motor pulse

      Min.: 0, Max.: 255

      -

      Air Inlet Damper Targ Pulse

      Damper servo sub-assembly target pulse

      Min.: 0, Max.: 255

      -

      OK

      Arm of the servo motor selected in the Active Test moves smoothly.

    2. According to the test, proceed to the next step.

      Table 2. Result

      Result

      Proceed to

      Malfunction in air mix control servo motor LH

      A

      Malfunction in air outlet control servo motor

      B

      Malfunction in damper servo sub-assembly

      C

      Malfunction in air mix control servo motor RH

      D

      All of the servo motors are malfunctioning

      E

    CHECK AIR OUTLET CONTROL SERVO MOTORClick here

    CHECK DAMPER SERVO SUB-ASSEMBLYClick here

    CHECK AIR MIX CONTROL SERVO MOTOR RHClick here

    CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY)Click here

  2. CHECK AIR MIX CONTROL SERVO MOTOR LH

    1. Replace the air mix control servo motor LH (Click here).

      Tip:

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

    2. Check for the DTCs.

      Table 3. Result

      Result

      Proceed to

      DTC B1497/97 is not output

      A

      DTC B1497/97 is output

      B

    END (AIR MIX CONTROL SERVO MOTOR LH IS DEFECTIVE)

    CHECK AIR CONDITIONING HARNESS ASSEMBLYClick here

  3. CHECK AIR OUTLET CONTROL SERVO MOTOR

    1. Replace the air outlet control servo motor LH (Click here).

      Tip:

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

    2. Check for the DTCs.

      Table 4. Result

      Result

      Proceed to

      DTC B1497/97 is not output

      A

      DTC B1497/97 is output

      B

    END (AIR OUTLET CONTROL SERVO MOTOR IS DEFECTIVE)

    CHECK AIR CONDITIONING HARNESS ASSEMBLYClick here

  4. CHECK DAMPER SERVO SUB-ASSEMBLY

    1. Replace the damper servo sub-assembly (Click here).

      Tip:

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

    2. Check for the DTCs.

      Table 5. Result

      Result

      Proceed to

      DTC B1497/97 is not output

      A

      DTC B1497/97 is output

      B

    END (DAMPER SERVO SUB-ASSEMBLY IS DEFECTIVE)

    CHECK AIR CONDITIONING HARNESS ASSEMBLYClick here

  5. CHECK AIR MIX CONTROL SERVO MOTOR RH

    1. Replace the air mix control servo motor RH (Click here).

      Tip:

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

    2. Check for the DTCs.

      Table 6. Result

      Result

      Proceed to

      DTC B1497/97 is not output

      A

      DTC B1497/97 is output

      B

    END (AIR MIX CONTROL SERVO MOTOR RH IS DEFECTIVE)

  6. CHECK AIR CONDITIONING HARNESS ASSEMBLY

    1. Replace the air conditioning harness assembly (Click here).

      Tip:

      Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a new or a known good one and check that the condition returns to normal.

    2. Check for the DTCs.

      Table 7. Result

      Result

      Proceed to

      DTC B1497/97 is not output

      A

      DTC B1497/97 is output

      B

    END (AIR CONDITIONING HARNESS IS DEFECTIVE)

  7. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY)

    1. U123879E02

      Disconnect the H46 air conditioning amplifier connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      H46-21 (B) - Body ground

      Always

      11 to 14 V
      Table 8. Text in Illustration

      *1

      Rear view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    (Click here)

    REPAIR OR REPLACE HARNESS OR CONNECTOR