Toyota Camry (XV70): Sliding Roof ECU Communication Stop (B1273)

DESCRIPTION

This DTC is stored when LIN communication between the sliding roof ECU (sliding roof drive gear sub-assembly)*1 or sliding roof ECU (sliding roof drive gear assembly)*2 and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B1273	Sliding Roof ECU Communication Stop	No communication between sliding roof ECU (sliding roof drive gear sub-assembly)*1 or sliding roof ECU (sliding roof drive gear assembly)*2 and main body ECU (multiplex network body ECU) for 10 seconds or more.	Main body ECU (multiplex network body ECU) Instrument panel junction block assembly Sliding roof ECU (sliding roof drive gear sub-assembly)*1 Sliding roof ECU (sliding roof drive gear assembly)*2 Wire harness or connector S/ROOF fuse

• *1: w/ Sliding Roof System
• *2: w/ Panoramic Moon Roof System

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

• Inspect the fuses for circuits related to this system before performing the following procedure.
• Before replacing the main body ECU (multiplex network body ECU), refer to Registration.*1

  Click here

• When the sliding roof ECU (sliding roof drive gear sub-assembly) is replaced or removed and reinstalled, it is necessary to perform initialization.*2

  Click here

• When the sliding roof ECU (sliding roof drive gear assembly) is replaced or removed and reinstalled, it is necessary to perform initialization.*3

  Click here

• *1: w/ Smart Key System
• *2: w/ Sliding Roof System
• *3: w/ Panoramic Moon Roof System

PROCEDURE

1.	INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here

*a

Component without harness connected (Instrument Panel Junction Block Assembly)

-

-

(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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

HINT:

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3B-17 - MB-16 (LIN2)	Always	Below 1 Ω

Result	Proceed to
OK (w/ Sliding Roof System)	A
OK (w/ Panoramic Moon Roof System)	B
NG	C

B

GO TO STEP 6

C

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

A

2.	CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY))

(a) Disconnect the V2 sliding roof ECU (sliding roof drive gear sub-assembly) connector.

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

NOTICE:

Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection	Condition	Specified Condition
3B-17 - V2-7 (MPX1)	Ignition switch off	Below 1 Ω
V2-7 (MPX1) or 3B-17 - Body ground	Ignition switch off	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.	CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) - BATTERY, BODY GROUND)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
V2-1 (B) - V2-2 (E)	Always	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
V2-2 (E) - Body ground	Always	Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.	REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)

(a) Replace the sliding roof ECU (sliding roof drive gear sub-assembly).

Click here

NEXT

5.	CHECK FOR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTC B1273 is not output.

OK

END (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY) WAS DEFECTIVE)

NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

6.	CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY))

(a) Disconnect the q1 sliding roof ECU (sliding roof drive gear assembly) connector.

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

NOTICE:

Make sure that each ECU is in sleep mode before performing the inspection. To enter sleep mode, turn the ignition switch from ON to off and wait for 180 seconds or more without operating any switches.

Standard Resistance:

Tester Connection	Condition	Specified Condition
3B-17 - q1-7 (LIN)	Ignition switch off	Below 1 Ω
q1-7 (LIN) or 3B-17 - Body ground	Ignition switch off	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

7.	CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) - BATTERY, BODY GROUND)

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
q1-1 (+B) - q1-2 (E)	Always	11 to 14 V

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
q1-2 (E) - Body ground	Always	Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

8.	REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

(a) Replace the sliding roof ECU (sliding roof drive gear assembly).

Click here

NEXT

9.	CHECK FOR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

(b) Recheck for DTCs.

Body Electrical > Main Body > Trouble Codes

OK:

DTC B1273 is not output.

OK

END (SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY) WAS DEFECTIVE)

NG

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

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