Lexus IS250 · Service Manual BODY ELECTRICAL

Door Courtesy Switch Circuit

Circuit diagnosis

DESCRIPTION

The main body ECU RH detects the condition of each door courtesy switch and sends a signal to each ECU via the multiplex communication circuit.

WIRING DIAGRAM

E123473E02
E123472E01

INSPECTION PROCEDURE

HINT:
The procedure is the same for each door courtesy switch circuit. First, inspect the suspected door courtesy switch circuit.


1. READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Turn the intelligent tester main switch on.

  1. Select the item below in the DATA LIST for proper functioning of the courtesy switch.

    DATA LIST: Main Body (Main Body ECU LH) 
    Item
    		 Measurement Item / Display
    (Range)
    		 Normal Condition
    		 Diagnostic Note
    D Door Courtesy Switch
    		 Driver side door courtesy switch / ON or OFF
    		 ON: Driver side door is open
    OFF: Driver side door is closed
    		 -
    P Door Courtesy Switch
    		 Passenger side door courtesy switch / ON or OFF
    		 ON: Passenger side door is open
    OFF: Passenger side door is closed
    		 -
    Rear Door Courtesy Switch
    		 Rear (LH and RH) door courtesy switch / ON or OFF
    		 ON: Rear door (LH or RH) is open
    OFF: Rear door (LH and RH) is closed
    		 -

    OK:
    Condition sign can be displayed.


    Result:
    Result
    		 Proceed to
    OK
    		 A
    Driver side door courtesy switch does not operate
    		 B
    Front passenger side door courtesy switch does not operate
    		 C
    Both rear door courtesy switches do not operate
    		 D



B
Go to step 2

C
Go to step 4

D
Go to step 6
A

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

2. INSPECT DOOR COURTESY SWITCH (FRONT LH)
Inspection (Click here)

OK:
Door courtesy switch is normal.



 NG
REPLACE DOOR COURTESY SWITCH (FRONT LH)
OK


3. CHECK HARNESS AND CONNECTOR (DOOR COURTESY SWITCH (FRONT LH) - MAIN BODY ECU RH)

  1. E108573E14
    Disconnect the P1 ECU connector.

  1. Disconnect the Q11 switch connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    LHD:
    Tester Connection
    		 Condition
    		 Specified Condition
    P1-14 (DCTY) - Q11-1
    		 Always
    		 Below 1 Ω
    P1-14 (DCTY) or Q11-1 - Body ground
    		 Always
    		 10 kΩ or higher
    RHD:
    Tester Connection
    		 Condition
    		 Specified Condition
    P1-14 (DCTY) - P8-1
    		 Always
    		 Below 1 Ω
    P1-14 (DCTY) or P8-1 - Body ground
    		 Always
    		 10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU RH (COWL SIDE J/B RH)

4. INSPECT DOOR COURTESY SWITCH (FRONT RH)
Inspection (Click here)

OK:
Door courtesy switch is normal.



 NG
REPLACE DOOR COURTESY SWITCH (FRONT RH)
OK


5. CHECK HARNESS AND CONNECTOR (DOOR COURTESY SWITCH (FRONT RH) - MAIN BODY ECU RH)

  1. E108574E06
    Disconnect the J75 ECU connector.

  1. Disconnect the P8 switch connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    RHD:
    Tester Connection
    		 Condition
    		 Specified Condition
    J75-23 (PCTY) - P8-1
    		 Always
    		 Below 1 Ω
    J75-23 (PCTY) or P8-1 - Body ground
    		 Always
    		 10 kΩ or higher
    LHD:
    Tester Connection
    		 Condition
    		 Specified Condition
    J75-23 (PCTY) - Q11-1
    		 Always
    		 Below 1 Ω
    J75-23 (PCTY) or Q11-1 - Body ground
    		 Always
    		 10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU RH (COWL SIDE J/B RH)

6. INSPECT DOOR COURTESY SWITCH (REAR LH AND REAR RH)
Inspection (Click here)

OK:
Door courtesy switch is normal.



 NG
REPLACE DOOR COURTESY SWITCH (REAR LH OR REAR RH)
OK


7. CHECK HARNESS AND CONNECTOR (DOOR COURTESY SWITCH (REAR LH OR REAR RH) - MAIN BODY ECU RH)

  1. E108575E06
    Check the wire harness between the cowl side junction block RH and door courtesy switch (rear LH).

    1. Disconnect the RA junction block connector.

    2. Disconnect the Q17 switch connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance:
      Tester Connection
      		 Condition
      		 Specified Condition
      RA-11 (LCTY) - Q17-1
      		 Always
      		 Below 1 Ω
      RA-11(LCTY) or Q17-1 - Body ground
      		 Always
      		 10 kΩ or higher

  1. E125299E01
    Check the wire harness between the main body ECU RH and door courtesy switch (rear RH).

    1. Disconnect the P1 ECU connector.

    2. Disconnect the P16 switch connector.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance:
      Tester Connection
      		 Condition
      		 Specified Condition
      P1-16 (RCTY) - P16-1
      		 Always
      		 Below 1 Ω
      P1-16 (RCTY) or P16-1 - Body ground
      		 Always
      		 10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU RH (COWL SIDE J/B RH)


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