B1273

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

DTC B1273 - Sliding Roof ECU Communication Stop

DESCRIPTION

This DTC is output when LIN communication between the sliding roof drive gear and main body ECU stops for 10 seconds or more.






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTE: When using the intelligent tester or Techstream with the power switch OFF to troubleshoot:

Connect the intelligent tester or Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.
HINT: DTC B2325 is output when the communication between all of the following components and main body ECU (driver side junction block) stops.

PROCEDURE

1. CLEAR DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
2. CHECK FOR DTC
(a) Recheck for DTC Reading and Clearing Diagnostic Trouble Codes.

Result:





B -- USE SIMULATION METHOD TO CHECK
A -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SLIDING ROOF DRIVE GEAR)





(a) Disconnect the L11 ECU connector.
(b) Disconnect the X5 gear connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (SLIDING ROOF DRIVE GEAR - BATTERY AND BODY GROUND)





(a) Disconnect the X5 gear connector.
(b) Measure the resistance and voltage according to the value(s) in the table below.
Standard resistance:






Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. CHECK SLIDING ROOF DRIVE GEAR SUB-ASSEMBLY (OPERATION)
(a) Temporarily replace the sliding roof gear with a new or normally functioning one Disassembly.
(b) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
NEXT -- Continue to next step.
6. CHECK FOR DTC
(a) Recheck for DTC Reading and Clearing Diagnostic Trouble Codes.

Result:





B -- REPLACE MAIN BODY ECU
A -- END (SLIDING ROOF DRIVE GEAR IS DEFECTIVE)