Toyota 4Runner: Wireless Door Lock Tuner Circuit Malfunction (B1242)

Toyota 4Runner Service Manual / Vehicle Interior / Door Lock / Wireless Door Lock Control System(w/o Smart Key System) / Wireless Door Lock Tuner Circuit Malfunction (B1242)

DESCRIPTION

The door control receiver receives signals from the transmitter and sends these signals to the main body ECU. This DTC is stored when the applicable RDA signal cannot be received within 1 second of the PRG signal being output from the main body ECU.

DTC Code	DTC Detection Condition	Trouble Area
B1242	The applicable RDA signal cannot be received within 1 second of the PRG signal being output from the main body ECU.	Harness or connector Door control receiver Main body ECU (multiplex network body ECU)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.
When replacing the door control receiver, refer to the registration procedures (See page ).

PROCEDURE

CLEAR DTC

(a) Clear the DTCs (See page ).

2.	CHECK FOR DTC

(a) Check for DTCs (See page ).

OK:

DTC B1242 is not output.

USE SIMULATION METHOD TO CHECK

3.	CHECK DOOR CONTROL RECEIVER (DOOR CONTROL RECEIVER - MAIN BODY ECU)

(a) Disconnect the O11 receiver connector.

(b) Disconnect the F9 ECU connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
O11-2 (RDA) - F9-26 (RDA)	Always	Below 1 Ω
O11-3 (PRG) - F9-25 (PRG)	Always	Below 1 Ω
O11-2 (RDA) or F9-26 (RDA) - Body ground	Always	10 kΩ or higher
O11-3 (PRG) or F9-25 (PRG) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK HARNESS AND CONNECTOR (DOOR CONTROL RECEIVER - BATTERY AND BODY GROUND)

(a) Disconnect the O11 receiver connector.

(b) Measure the resistance and voltage according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
O11-1 (GND) - Body ground	Always	Below 1 Ω

Standard Voltage:

Tester Connection	Condition	Specified Condition
O11-5 (+B) - Body ground	Always	11 to 14 V

Text in Illustration

*a	Front view of wire harness connector (to Door Control Receiver)

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	REPLACE DOOR CONTROL RECEIVER

(a) Temporarily replace the door control receiver with a new one (See page ).

(b) Perform the registration procedures (See page ).

CLEAR DTC

(a) Clear the DTCs (See page ).

7.	CHECK FOR DTC

(a) Check for DTCs (See page ).

OK:

DTC B1242 is not output.

END (DOOR CONTROL RECEIVER IS DEFECTIVE)

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART HINT: If a trouble code is output during the DTC check, inspect the trouble areas listed for that code. For details of the code, refer to the "See page" bel ...

Only Wireless Control Function is Inoperative

DESCRIPTION The door control receiver receives signals from the transmitter and sends these signals to the main body ECU. The main body ECU then controls all the doors by sending lock/unlock sign ...

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