Toyota Tacoma (2015-2018) Service Manual: P/W Master Switch Communication Stop (B1206)

Toyota Tacoma (2015-2018) Service Manual / Multiplex Communication / Lin Communication System / P/W Master Switch Communication Stop (B1206)

DESCRIPTION

This DTC is stored when LIN communication between the power window regulator master switch assembly and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No.	DTC Detection Condition	Trouble Area
B1206	No communication between power window regulator master switch assembly and main body ECU (multiplex network body ECU) for 10 seconds or more.	Power window regulator master switch assembly Main body ECU (multiplex network body ECU) Driver side junction block Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.
If the main body ECU (multiplex network body ECU) is replaced, refer to Registration (See page )

PROCEDURE

1.	INSPECT DRIVER SIDE JUNCTION BLOCK

(a) Remove the driver side junction block (See page (b) Remove the main body ECU (multiplex network body ECU) from the driver side ).

(b) Remove the main body ECU (multiplex network body ECU) from the driver side junction block.

Standard Resistance:

Tester Connection	Condition	Specified Condition
1D-13 - MB-16 (LIN2)	Always	Below 1 Ω

Text in Illustration

Component without harness connected

(Driver Side Junction Block)

HINT:

This inspection is to check the LIN line in the driver side junction block that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

REPLACE DRIVER SIDE JUNCTION BLOCK

2.	CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK - POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY)

(a) for Double Cab

(1) Disconnect the 1D driver side junction block connector.

(2) Disconnect the P18 power window regulator master switch assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
1D-13 - P18-6 (LIN1)	Always	Below 1 Ω
1D-13 or P18-6 (LIN1) - Body ground	Always	10 kΩ or higher

(b) for Access Cab

(1) Disconnect the 1D driver side junction block connector.

(2) Disconnect the P23 power window regulator master switch assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
1D-13 - P23-17 (LIN1)	Always	Below 1 Ω
1D-13 or P23-17 (LIN1) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	CHECK HARNESS AND CONNECTOR (POWER WINDOW REGULATOR MASTER SWITCH - POWER SOURCE CIRCUIT)

(a) for Double Cab

(1) Disconnect the P18 power window regulator master switch assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
P18-3 (B) - P18-1 (GND)	Always	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
P18-1 (GND) - Body ground	Always	Below 1 Ω

(b) for Access Cab

(1) Disconnect the P23 power window regulator master switch assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
P23-11 (B) - P23-12 (GND)	Always	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
P23-12 (GND) - Body ground	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY

(a) Replace the power window regulator master switch assembly.

5.	CHECK DTC OUTPUT

(a) Clear the DTCs (See page (b) Recheck for DTCs. ).

(b) Recheck for DTCs.

OK:

DTC B1206 is not output.

END (POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY WAS DEFECTIVE)

REPLACE MAIN BODY ECU (MULTIPLEX BODY ECU)

LIN Communication Bus Malfunction (B2325)

DESCRIPTION The main body ECU (multiplex network body ECU) monitors communication between all the ECUs connected to the door bus lines. When the main body ECU (multiplex network body ECU) detects ...

Lost Communication with Power Source Control (B278C)

DESCRIPTION DTC No. DTC Detection Condition Trouble Area B278C An internal malfunction occurs in the certification ECU (smart key ECU ...

Other materials:

On-vehicle Inspection
ON-VEHICLE INSPECTION PROCEDURE 1. INSPECT RADIATOR CAP SUB-ASSEMBLY CAUTION: Do not remove the radiator cap sub-assembly while the engine and radiator assembly are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns. (a) Measure the valve opening pr ...

Problem Symptoms Table
PROBLEM SYMPTOMS TABLE HINT: Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each sy ...

Occupant Classification ECU Malfunction (B1795)
DESCRIPTION DTC B1795 is set when a malfunction is detected in the occupant detection ECU. Troubleshoot DTC B1771 first when both DTCs B1771 and B1795 are present. DTC No. DTC Detections Conditions Trouble Areas B1795 Occupant detection ...