B1262

MULTIPLEX COMMUNICATION: 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 A/C No. 2 amplifier (A/C ECU) and network gateway ECU stops for more than 10 seconds.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OPERATION
(a) Check that the A/C switch can operate the A/C normally.
OK:
A/C switch can operate A/C normally.
OK -- REPLACE AIR CONDITIONING NO. 2 AMPLIFIER
NG -- Continue to next step.
2.
CHECK WIRE HARNESS (AIR CONDITIONING NO. 2 AMPLIFIER - BATTERY AND BODY GROUND)




(a) Disconnect the K52 ECU connector.
(b) Measure the resistance and voltage of the wire harness side connector.
Standard resistance:





Standard voltage





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK RESISTANCE OF COMMUNICATION LINE




(a) Disconnect the K52 ECU connector.
(b) Disconnect the K12 panel connector.
(c) Disconnect the K44 sensor connector.
(d) Measure the resistance of the wire harness side connectors.
Standard resistance:






Result





C -- REPAIR OR REPLACE HARNESS OR CONNECTOR
B -- REPAIR OR REPLACE AIR CONDITIONING NO. 2 AMPLIFIER AND WIRE HARNESS OR CONNECTOR
A -- REPLACE AIR CONDITIONING NO. 2 AMPLIFIER