B1262

MULTIPLEX COMMUNICATION SYSTEM: B1262: A/C ECU Communication Stop

DTC B1262 - A/C ECU Communication Stop

DESCRIPTION
- This DTC is detected when communication between the air conditioning amplifier (A/C 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 B1262, repair the "+B or GND short malfunction of communication bus" DTCs first.

PROCEDURE

1. CHECK FUSE (ECU-IG NO. 1)
(a) Remove the ECU-IG No. 1 fuse from the fusible link block.
(b) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER ASSEMBLY - BATTERY AND BODY GROUND)

(a) Disconnect the A8 ECU connector.
(b) Measure the voltage of the wire harness side connector.
Standard voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK RESISTANCE OF COMMUNICATION LINE
(a) Disconnect the G3 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 AIR CONDITIONING AMPLIFIER ASSEMBLY