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 and main body ECU (cowl side junction block LH) stops for 10 seconds or more.

WIRING DIAGRAM

INSPECTION PROCEDURE
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.
HINT:
DTC B2325 is stored when the communication between the sliding roof ECU and main body ECU (cowl side junction block LH) 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 DTCs 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 ECU)

(a) Disconnect the E3 and R5 ECU connectors.
(b) Measure the resistance and voltage according to the value(s) in the tables below.
Standard Resistance:

Standard Voltage:

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

(a) Disconnect the R5 ECU connector.
(b) Measure the resistance and voltage according to the value(s) in the tables below.
Standard Resistance:

Standard Voltage:

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

Result

B -- REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)
A -- END (SLIDING ROOF ECU IS DEFECTIVE)