B1245

MULTIPLEX COMMUNICATION SYSTEM: B1245: Wiper ECU Communication Stop

DTC B1245 - Wiper ECU Communication Stop

DESCRIPTION
- This DTC is detected when communication between the auto wiper ECU and multiplex network gateway ECU stops for more than 10 seconds.





WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: When "+B or GND short malfunction of communication bus" DTCs (B1266 and B1267) are detected at the same time as "communication stop" DTC B1245, repair the "+B or GND short malfunction of communication bus" DTCs first.

PROCEDURE

1. CHECK OPERATION
(a) Turn the ignition switch to the ON position.
(b) Check that the auto wiper can be operated using the wiper and washer switch.
HINT: With this inspection, the auto wiper ECU CPU can be diagnosed if it works normally or not.

OK:
Auto wiper can be operated using wiper and washer switch.
NG -- CHECK RESISTANCE OF COMMUNICATION LINE
OK -- Continue to next step.
2. INSPECT FUSE (FR WIP)
(a) Remove the FR WIP fuse from the instrument panel junction block.
(b) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (AUTO WIPER ECU - BATTERY AND BODY GROUND)





(a) Disconnect the A28 and A29 ECU connectors.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage of the wire harness side connector.
Standard voltage:





(d) Measure the resistance of the wire harness side connector.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK RESISTANCE OF COMMUNICATION LINE
(a) Disconnect the A8 and A20 ECU connectors.





(b) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE AUTO WIPER ECU