Dtc B1497/97 Bus Ic Communication Malfunction


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

PERFORM ACTIVE TEST USING INTELLIGENT TESTER

SYSTEM CHECK

CHECK DAMPER SERVO SUB-ASSEMBLY (DRIVER SIDE AIR MIX DAMPER SERVO)

CHECK DAMPER SERVO SUB-ASSEMBLY (FRONT PASSENGER SIDE AIR MIX DAMPER SERVO)

CHECK DAMPER SERVO SUB-ASSEMBLY (MODE DAMPER SERVO)

CHECK RECIRCULATION DAMPER SERVO SUB-ASSEMBLY

CHECK AIR CONDITIONING HARNESS ASSEMBLY

SYSTEM CHECK

CHECK REAR AIR MIX DAMPER SERVO SUB-ASSEMBLY

CHECK REAR MODE DAMPER SERVO SUB-ASSEMBLY

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - NO. 2 AIR CONDITIONING HARNESS ASSEMBLY)

CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY

DTC 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.
  1. Recirculation damper servo sub-assembly
  2. Damper servo sub-assembly
  3. Damper servo sub-assembly
  4. Rear air mix damper servo sub-assembly*
  5. Rear mode damper servo sub-assembly*
  6. Air conditioning harness assembly
  7. No. 2 air conditioning harness assembly*
  8. Air conditioning amplifier assembly
  9. Harness or connector
  1. *: w/ Rear Air Conditioning System

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1497/97 Bus Ic Communication Malfunction


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1497/97 Bus Ic Communication Malfunction


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.CHECK HARNESS AND CONNECTOR (POWER SOURCE)
Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc B1497/97 Bus Ic Communication Malfunction
*: w/ Rear Air Conditioning System

  1. Disconnect the G24* and G25 air conditioning amplifier assembly connector.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    G25-21 (B) - Body ground
    		Always
    		11 to 14 V
    G24-24 (+B2) - Body ground*
    		Always
    		11 to 14 V

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    G25-14 (GND) - Body ground
    		Always
    		Below 1 Ω
    G24-20 (RGND) - Body ground*
    		Always
    		Below 1 Ω
    Text in Illustration
    *A
    		w/ Rear Air Conditioning System
    *a
    		Front view of wire harness connector
    (to Air Conditioning Amplifier Assembly)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.PERFORM ACTIVE TEST USING INTELLIGENT TESTER

  1. Select the Active Test, use the intelligent tester to generate a control command, and then check that the servo motor operates (LandCruiser RM000002LIV040X.html).

    Air Conditioner
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Air Mix Servo Targ Pulse (D)
    		Damper servo sub-assembly (driver side air mix damper servo) target pulse
    		Min.: 0, Max.: 255
    		-
    Air Mix Servo Targ Pulse (P)
    		Damper servo sub-assembly (front passenger side air mix damper servo) pulse
    		Min.: 0, Max.: 255
    		-
    Air Outlet Servo Pulse (D)
    		Damper servo sub-assembly (mode damper servo) pulse
    		Min.: 0, Max.: 255
    		-
    Air Inlet Damper Targ Pulse
    		Recirculation damper servo sub-assembly target pulse
    		Min.: 0, Max.: 255
    		-
    Rear Air Mix Servo Targ Pulse*
    		Rear air mix damper servo sub-assembly target pulse
    		Min.: 0, Max.: 255
    		-
    A/O Servo Pulse(Rr D)*
    		Rear mode damper servo sub-assembly pulse
    		Min.: 0, Max.: 255
    		-
    1. *: w/ Rear Air Conditioning System
    OK:
    Arm of the servo motor selected in the Active Test moves smoothly

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

    Result
    Result
    		Proceed to
    One of the front servo motors is malfunctioning
    		A
    All of the front servo motors are malfunctioning
    		B
    One of the rear servo motors is malfunctioning
    		C
    All of the rear servo motors are malfunctioning
    		D


B
Go to step 8

C
Go to step 9

D
Go to step 12
A


3.SYSTEM CHECK

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

    Result
    Result
    		Proceed to
    Only the damper servo sub-assembly (driver side air mix damper servo) is malfunctioning
    		A
    Only the damper servo sub-assembly (front passenger side air mix damper servo) is malfunctioning
    		B
    Only the damper servo sub-assembly (mode damper servo) is malfunctioning
    		C
    Only the recirculation damper servo sub-assembly is malfunctioning
    		D


B
Go to step 5

C
Go to step 6

D
Go to step 7
A


4.CHECK DAMPER SERVO SUB-ASSEMBLY (DRIVER SIDE AIR MIX DAMPER SERVO)

  1. Replace the damper servo sub-assembly (driver side air mix damper servo) (LandCruiser RM000003AXS04FX.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 8
A

END (DAMPER SERVO SUB-ASSEMBLY [DRIVER SIDE AIR MIX DAMPER SERVO] IS FAULTY)

5.CHECK DAMPER SERVO SUB-ASSEMBLY (FRONT PASSENGER SIDE AIR MIX DAMPER SERVO)

  1. Replace the damper servo sub-assembly (front passenger side air mix damper servo) (LandCruiser RM000003AXS04FX.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 8
A

END (DAMPER SERVO SUB-ASSEMBLY [FRONT PASSENGER SIDE AIR MIX DAMPER SERVO] IS FAULTY)

6.CHECK DAMPER SERVO SUB-ASSEMBLY (MODE DAMPER SERVO)

  1. Replace the damper servo sub-assembly (mode damper servo) (LandCruiser RM000003AXS04FX.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 8
A

END (DAMPER SERVO SUB-ASSEMBLY [MODE DAMPER SERVO] IS FAULTY)

7.CHECK RECIRCULATION DAMPER SERVO SUB-ASSEMBLY

  1. Replace the recirculation damper servo sub-assembly (LandCruiser RM000003B3T024X.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 8
A

END (RECIRCULATION DAMPER SERVO SUB-ASSEMBLY IS FAULTY)

8.CHECK AIR CONDITIONING HARNESS ASSEMBLY

  1. Replace the air conditioning harness assembly (LandCruiser RM000003AXS04FX.html).

    HINT:
    Since the air conditioning harness assembly cannot be inspected while it is removed from the vehicle, replace the air conditioning harness assembly with a new or a known good one and check that the condition returns to normal.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (LandCruiser RM0000039R5028X.html)
A

END (AIR CONDITIONING HARNESS ASSEMBLY IS FAULTY)

9.SYSTEM CHECK

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

    Result
    Result
    		Proceed to
    Only the rear air mix damper servo sub-assembly is malfunctioning
    		A
    Only the rear mode damper servo sub-assembly is malfunctioning
    		B


B
Go to step 11
A


10.CHECK REAR AIR MIX DAMPER SERVO SUB-ASSEMBLY

  1. Replace the rear air mix damper servo sub-assembly (LandCruiser RM000001JR303LX.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 12
A

END (REAR AIR MIX DAMPER SERVO SUB-ASSEMBLY IS FAULTY)

11.CHECK REAR MODE DAMPER SERVO SUB-ASSEMBLY

  1. Replace the rear mode damper servo sub-assembly (LandCruiser RM000001JR303LX.html).

    HINT:
    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.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
Go to step 12
A

END (REAR MODE DAMPER SERVO SUB-ASSEMBLY IS FAULTY)

12.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - NO. 2 AIR CONDITIONING HARNESS ASSEMBLY)

  1. Disconnect the Q13 No. 2 air conditioning harness assembly connector.

  1. Disconnect the G24 air conditioning amplifier assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    G24-23 (RBBU) - Q13-4 (RBBU)
    		Always
    		Below 1 Ω
    G24-1 (RBUS) - Q13-3 (RBUS)
    		Always
    		Below 1 Ω
    G24-21 (RBUG) - Q13-2 (RBUG)
    		Always
    		Below 1 Ω
    G24-23 (RBBU) - Body ground
    		Always
    		10 kΩ or higher
    G24-1 (RBUS) - Body ground
    		Always
    		10 kΩ or higher
    G24-21 (RBUG) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


13.CHECK NO. 2 AIR CONDITIONING HARNESS ASSEMBLY

  1. Replace the No. 2 air conditioning harness assembly (LandCruiser RM000001JR303LX.html).

    HINT:
    Since the No. 2 air conditioning harness assembly cannot be inspected while it is removed from the vehicle, replace the No. 2 air conditioning harness assembly with a new or a known good one and check that the condition returns to normal.

  1. Check for DTCs.

    Result
    Result
    		Proceed to
    DTC B1497/97 is not output
    		A
    DTC B1497/97 is output
    		B


B
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (LandCruiser RM0000039R5028X.html)
A

END (NO. 2 AIR CONDITIONING HARNESS ASSEMBLY IS FAULTY)