B278A

ENGINE IMMOBILIZER: ENGINE IMMOBILIZER SYSTEM: B278A: Short to GND in Immobilizer System Power Source Circuit

DTC B278A - Short to GND in Immobilizer System Power Source Circuit

DESCRIPTION

This DTC is output when the engine switch power source supply line is open or short.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK WIRE HARNESS (CERTIFICATION ECU - ENGINE SWITCH)




(a) Disconnect the U28 and K29 switch connectors.
(b) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

2. CHECK OPERATION OF ENGINE SWITCH
(a) After replacing the engine switch with a normal one, check that the engine starts Engine Immobilizer System.
OK:
Engine starts.
NG -- REPLACE CERTIFICATION ECU
OK -- REPLACE ENGINE SWITCH