Dtc B1242 Wireless Door Lock Tuner Circuit Malfunction

Vehicle Interior. Yaris. Ncp93, 131
Door Lock. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - DOOR CONTROL RECEIVER)

INSPECT DOOR CONTROL RECEIVER (+B TERMINAL)

INSPECT DOOR CONTROL RECEIVER (GND TERMINAL)

REPLACE DOOR CONTROL RECEIVER

RECHECK DTC

DTC B1242 Wireless Door Lock Tuner Circuit Malfunction


DESCRIPTION

The door control receiver receives signals from the transmitter and sends these signals to the main body ECU.

DTC No.
DTC Detection Condition
Suspected Area
B1242
In diagnostic mode, applicable RDA signal cannot be received within 1 second of PRG signal being output from main body ECU.
  1. Wire harness
  2. Door control receiver
  3. Main body ECU

WIRING DIAGRAM


Yaris. Ncp93, 131.Door Lock.Power Door Lock Control System (For Sedan). Dtc B1242 Wireless Door Lock Tuner Circuit Malfunction


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - DOOR CONTROL RECEIVER)


    Yaris. Ncp93, 131.Door Lock.Power Door Lock Control System (For Sedan). Dtc B1242 Wireless Door Lock Tuner Circuit Malfunction

  1. Disconnect the D33 main body ECU connector.

  1. Disconnect the J13 door control receiver connector.

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Specified Condition
    D33-16 (RDA) - J13-2 (RDA)
    		Below 1 Ω
    D33-16 (RDA) or J13-2 (RDA) - Body ground
    		10 kΩ or higher
    D33-17 (PRG) - J13-3 (PRG)
    		Below 1 Ω
    D33-17 (PRG) or J13-3 (PRG) - Body ground
    		10 kΩ or higher

  1. Reconnect the main body ECU connector.

  1. Reconnect the door control receiver connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.INSPECT DOOR CONTROL RECEIVER (+B TERMINAL)

  1. Disconnect the J13 door control receiver connector.



    Yaris. Ncp93, 131.Door Lock.Power Door Lock Control System (For Sedan). Dtc B1242 Wireless Door Lock Tuner Circuit Malfunction

  1. Measure the voltage.

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    J13-5 (+B) - Body ground
    		Always
    		11 to 14 V

  1. Reconnect the door control receiver connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (+B CIRCUIT)
OK


3.INSPECT DOOR CONTROL RECEIVER (GND TERMINAL)

  1. Disconnect the J13 door control receiver connector.



    Yaris. Ncp93, 131.Door Lock.Power Door Lock Control System (For Sedan). Dtc B1242 Wireless Door Lock Tuner Circuit Malfunction

  1. Measure the resistance.

    Standard resistance:
    Tester Connection
    		Specified Condition
    J13-1 (GND) - Body ground
    		Below 1 Ω

  1. Reconnect the door control receiver connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (E CIRCUIT)
OK


4.REPLACE DOOR CONTROL RECEIVER

  1. Replace the door control receiver.

  1. Perform the REGISTRATION procedures (YARIS_NCP93 RM0000033J7008X.html).

    HINT:
    If a new or normal functioning door control receiver is available, connect it and check if the wireless door lock function is normal or the DTC is output. If the alternative receiver functions normally, replace the original door control receiver.

NEXT


5.RECHECK DTC

  1. Clear the DTC.

  1. Check if the same DTC is detected.

    HINT:
    Reinstall the parts, such as sensors and connectors, and restore the vehicle to its previous conditions before rechecking for DTCs.

    Result:
    Condition
    		Proceed to
    DTC (B1242) is output
    		A
    DTC (B1242) is not output (When troubleshooting in accordance with DTC CHART)
    		B
    DTC (B1242) is not output (When troubleshooting in accordance with PROBLEM SYMPTOMS TABLE)
    		C


B
END

C
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
A

REPLACE MAIN BODY ECU