Toyota Tundra Service Manual: Sliding Roof ECU Communication Stop (B1273)

Toyota Tundra Service Manual / Power Source, Network / Multiplex Communication / Lin Communication System / Sliding Roof ECU Communication Stop (B1273)

DESCRIPTION

This DTC is stored when LIN communication between the sliding roof drive gear sub-assembly and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No.

DTC Detection Condition

Trouble Area

B1273

No communication between sliding roof drive gear sub-assembly and main body ECU (multiplex network body ECU) for 10 seconds or more
  • Sliding roof drive gear sub-assembly (Sliding Roof ECU)
  • Driver side junction block assembly
  • Main body ECU (multiplex network body ECU)
  • 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 light 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 inspection procedure.
  • w/ Sliding Roof System:

    When the sliding roof drive gear sub-assembly is removed and reinstalled or replaced, the sliding roof drive gear sub-assembly must be initialized.

    Click here

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 B1273 is not output

USE SIMULATION METHOD TO CHECK

DTC B1273 is output

3.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

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

Click here

(b) Disconnect the W3 sliding roof drive gear sub-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) - W3-3 (LIN)

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 (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY - BATTERY AND BODY GROUND)

(a) Disconnect the sliding roof drive gear sub-assembly connector.

*a

Front view of wire harness connector

(to Sliding Roof Drive Gear Sub-assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

W3-8 (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

W3-10 (B) - Body ground

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

REPLACE SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY

(a) Temporarily replace the sliding roof drive gear sub-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 B1273 is not output

END (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY IS DEFECTIVE)
DTC B1273 is output

REPLACE BODY ECU (MULTIPLEX NETWORK BODY ECU)

7.

CHECK HARNESS AND CONNECTOR (DRIVER SIDE JUNCTION BLOCK ASSEMBLY - SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

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

Click here

(b) Disconnect the W3 sliding roof drive gear sub-assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3I-17 - W3-3 (LIN)

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
    P/W Master Switch Communication Stop (B1206)

    Driver Side Door ECU Communication Stop (B2321)

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