B1273

NETWORKING: LIN COMMUNICATION SYSTEM: B1273: Sliding Roof ECU Communication Stop

DTC B1273 - Sliding Roof ECU Communication Stop

DESCRIPTION

This DTC is stored when LIN communication between the sliding roof ECU (sliding roof drive gear sub-assembly) and main body ECU (driver side junction block assembly) stops for more than 10 seconds.





WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
- When the sliding roof ECU (sliding roof drive gear sub-assembly) is replaced or removed and reinstalled, it requires initialization Programming and Relearning.
- When using the Techstream to troubleshoot with the ignition switch off:
Connect the Techstream to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the Techstream and vehicle begins.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU - BATTERY AND BODY GROUND)




(a) Disconnect the P4 ECU connector.
(b) Measure the resistance and voltage according to the value(s) in the table below.
Standard Resistance:





Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SLIDING ROOF ECU)




(a) Disconnect the D48 ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

3. REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY)
(a) Replace the sliding roof ECU (sliding roof drive gear sub-assembly) Removal.
NEXT -- Continue to next step.

4. CHECK DTC OUTPUT
(a) Clear the DTC Initial Inspection and Diagnostic Overview.
(b) Recheck for DTCs.
OK:
DTC B1273 is not output.

NG -- REPLACE MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)
OK -- END (SLIDING ROOF ECU WAS DEFECTIVE)