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 power switch power source supply line is open or shorted.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

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




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






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
2. CHECK POWER SWITCH (OPERATION)
(a) Temporarily replace the power switch with a new or normally functioning one Removal.
(b) Check for DTC.
OK:
DTC B278A output does not reoccur.
NG -- REPLACE CERTIFICATION ECU
OK -- END (POWER SWITCH IS DEFECTIVE)