RX400h · Service Manual HEATER & AIR CONDITIONING SYSTEM

DIAGNOSIS SYSTEM

Troubleshooting


LIST OF OPERATION METHODS
By operating each of the A/C control switches as shown in the diagram below, it is possible to enter the diagnostic check mode.
E109264E01

CHECK THE DLC3
C052361

  1. The vehicle's ECM uses the ISO 9141-2 (Euro-OBD)/ISO 14230 (M-OBD) communication protocol. The terminal arrangement of DLC3 complies with ISO 15031-3 and matches the ISO 9141-2/ISO 14230 format.

    Symbols (Terminal No.)
    		 Terminal Description
    		 Condition
    		 Specified Condition
    SILO (7) - SG (5)
    		 Bus "+" line
    		 During transmission
    		 Pulse generation
    CG (4) - Body ground
    		 Chassis ground
    		 Always
    		 Below 1 Ω
    SG (5) - Body ground
    		 Signal ground
    		 Always
    		 Below 1 Ω
    BAT (16) - Body ground
    		 Battery positive
    		 Always
    		 11 to 14 V
    CANH (6) - CANL (14)
    		 HIGH-level CAN bus line
    		 Ignition switch off
    		 54 to 67 Ω
    CANH (6) - Battery positive
    		 HIGH-level CAN bus line
    		 Ignition switch off
    		 1 MΩ or higher
    CANH (6) - CG (4)
    		 HIGH-level CAN bus line
    		 Ignition switch off
    		 3 KΩ or higher
    CANL (14) - Battery positive
    		 LOW-level CAN bus line
    		 Ignition switch off
    		 1 MΩ or higher
    CANL (14) - CG (4)
    		 LOW-level CAN bus line
    		 Ignition switch off
    		 3 KΩ or higher

    HINT:
    If the display shows a communication error message after connecting the intelligent tester cable to the DLC3 and turning the ignition switch to the ON position, there is a problem either with the vehicle or the tester.
    1. If communication is normal when connecting the tester to another vehicle, inspect the DLC3 on the original vehicle.
    2. If communication is still not possible when connecting the tester to another vehicle, the problem is probably in the tester itself. Consult the Service Department listed in the tester's operator's manual.


INDICATOR CHECK

  1. Turn the ignition switch to the ON position while pressing the A/C control "AUTO" switch and "R/F" switch simultaneously.
    E109220E02

  2. Check that the indicators come on and go off 4 times in succession at 1 second intervals.
    E109223E01

    HINT:
    1. If a navigation system is installed, the indicator will blink and buzzer will sound.
    2. After the indicator check is completed, the system enters the DTC mode automatically.
    3. Press the "OFF" switch to cancel the check mode.

← TERMINALS OF ECUDTC CHECK / CLEAR →