B1245 Auto wiper ECU Communication stops

DESCRIPTION

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

DTC No.	DTC Detection Condition	Trouble Area
B1245	Auto wiper ECU Communication stops	Auto wiper ECU Wire harness

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

When "+B of 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.

1. CHECK OPERATION

1. Turn the ignition switch on.

2. 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	Go to step 4

OK

2. INSPECT FUSE (FR WIP)

1. Remove the FR WIP fuse from the instrument panel junction block.

2. Measure the resistance of the fuse.

   Standard resistance:

   Below 1 Ω
   

NG	REPLACE FUSE

OK

3. CHECK WIRE HARNESS (AUTO WIPER ECU - BATTERY AND BODY GROUND)

1. Disconnect the A31 and A30 ECU connectors.

2. Turn the ignition switch on.

3. Measure the voltage of the wire harness side connector.

   Standard voltage:

   Tester Connection	Connection	Specified Connection
   A30-10 (WIG) - Body ground	Ignition switch ON	10 to 14 V

4. Measure the resistance of the wire harness side connector.

   Standard resistance:

   Tester Connection	Specified Connection
   A31-12 (E) - Body ground	Below 1 Ω

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4. CHECK RESISTANCE OF COMMUNICATION LINE

1. Disconnect the A11 and A24 ECU connectors.
   

2. Measure the resistance of the wire harness side connectors.

Standard resistance:

Tester Connection	Specified Condition
A31-1 (MPX1) - A11-3 (MPX+)	Below 1 Ω
A31-1 (MPX1) - A24-22 (MPX2)	Below 1 Ω

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE AUTO WIPER ECU