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 shorted.






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTE:
If the certification ECU is replaced, register the key and ECU communication ID Engine Immobilizer System.

PROCEDURE

1. CHECK DTC OUTPUT
(a) Delete the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Recheck for DTCs Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- USE SIMULATION METHOD TO CHECK
A -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ENGINE SWITCH)




(a) Disconnect the E13 ECU and E68 switch connectors.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH POWER SOURCE)




(a) Reconnect the E13 ECU and E68 switch connectors.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE CERTIFICATION ECU
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (ENGINE SWITCH BODY GROUND)




(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE CERTIFICATION ECU
OK -- REPLACE ENGINE SWITCH