Toyota Tundra Service Manual: P/W Master Switch Communication Stop (B1206)

Toyota Tundra Service Manual / Power Source, Network / 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 Code

DTC Detection Condition

Trouble Area

B1206

No communication between the 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 assembly
  • Harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off to troubleshoot:

    Connect the Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the Techstream and vehicle begins.

  • Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

DTC B2325 is output when the communication between all of the following components and main body ECU (multiplex network body ECU) stops.

Click here

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Click here

NEXT

2.

CHECK FOR DTC

(a) Check for DTCs.

Click here

DTC B1206 is not output

USE SIMULATION METHOD TO CHECK

DTC B1206 is output

3.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY)

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

Click here

(b) Disconnect the N2 power window regulator master switch assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A-16 (LIN2) - N2-6 (LIN1)

Always

Below 1 Ω

A-16 (LIN2) - Body ground

Always

10 kΩ or higher
NG

GO TO STEP 7

OK

4.

CHECK HARNESS AND CONNECTOR (POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY - BATTERY AND BODY GROUND)

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

*a

Front view of wire harness connector

(to Power Window Regulator Master Switch Assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

N2-1 (E) - Body ground

Always

Below 1 Ω

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

N2-3 (B) - Body ground

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

REPLACE POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY

(a) Temporarily replace the power window regulator master switch assembly with a new or normally functioning one.

Click here

(b) Clear the DTCs.

Click here

NEXT

6.

CHECK FOR DTC

(a) Check for DTCs.

Click here

DTC B1206 is not output

END (POWER WINDOW REGULATOR MASTER SWITCH ASSEMBLY IS DEFECTIVE)
DTC B1206 is output

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

7.

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

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

Click here

(b) Disconnect the N2 power window regulator master switch assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3I-17 - N2-6 (LIN1)

Always

Below 1 Ω

3I-17 - Body ground

Always

10 kΩ or higher
OK

REPLACE DRIVER SIDE JUNCTION BLOCK ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
    Lin Communication System

    Sliding Roof ECU Communication Stop (B1273)

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