B1280

DESCRIPTION

This DTC is detected when communication between the main body ECU LH (cowl side J/B LH) and gateway ECU stops for more than 10 seconds.

DTC No.	DTC Detection Condition	Trouble Area
B1280	Left side J/B ECU communication stops	Main body ECU LH (cowl side J/B LH) Wire harness

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

When "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1280, repair the "+B or GND short malfunction of communication bus" DTCs first.

1. INSPECT FUSE (MPX-B)

1. Remove the MPX-B from the engine room J/B No. 1.

2. Measure the resistance of the fuse.

   Standard resistance:

   Below 1 Ω
   

NG	REPLACE FUSE

OK

2. CHECK WIRE HARNESS (MAIN BODY ECU LH - BATTERY AND BODY GROUND)

1. Disconnect the LD ECU connector.

2. Measure the voltage and resistance of the wire harness side connector.

   Standard voltage:

   Tester Connection	Condition	Specified Condition
   MPX-B (LD-18) - Body ground	Always	10 to 14 V

   Standard resistance:

   Tester Connection	Specified Condition
   GND (LD-3) - Body ground	Below 1 Ω

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3. CHECK RESISTANCE OF COMMUNICATION LINE

1. Disconnect the Q3, A30, M7 and 2F ECU connectors (for LHD).

2. Disconnect the Q3, A30, P33 and 2F ECU connectors (for RHD).
   

3. Measure the resistance between the specified terminals on the wire harness side connectors.

   Standard resistance:

   Tester Connection	Specified Condition
   *1MPX1 (Q3-15) - MPX1 (M7-7) *2MPX1 (Q3-15) - MPX1 (P33-28)	Below 1 Ω
   *1MPX2 (A30-17) - 2F-6 *2MPX2 (A30-7) - 2F-6	Below 1 Ω

   HINT:

   1. *1: LHD
      
   2. *2: RHD
      

   Result:

   Result	Proceed to
   Both are OK	A
   One is OK	B
   Both are NG	C

B	REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE MAIN BODY ECU LH
C	REPAIR OR REPLACE HARNESS OR CONNECTOR

A
REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)