Dtc B278A Short To Gnd In Immobiliser System Power Source Circuit

Vehicle Interior. Land Cruiser. Urj200, 202 Grj200 Vdj200
Theft Deterrent Keyless Entry. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH)

REPLACE ENGINE SWITCH

CLEAR DTC

CHECK FOR DTC

DTC B278A Short to GND in Immobiliser System Power Source Circuit


DESCRIPTION

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

DTC Code
DTC Detection Condition
Trouble Area
B278A
The engine switch power source supply line is open or shorted.
  1. Harness or connector
  1. Engine switch
  1. Certification ECU (Smart key ECU)

WIRING DIAGRAM


Land Cruiser. Urj200, 202 Grj200 Vdj200.Theft Deterrent Keyless Entry.Entry And Start System (For Entry Function). Dtc B278A Short To Gnd In Immobiliser System Power Source Circuit


INSPECTION PROCEDURE

1.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH)

Land Cruiser. Urj200, 202 Grj200 Vdj200.Theft Deterrent Keyless Entry.Entry And Start System (For Entry Function). Dtc B278A Short To Gnd In Immobiliser System Power Source Circuit

  1. Disconnect the E29 ECU connector.

  1. Disconnect the E18 switch connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E29-30 (VC5) - E18-14 (VC5)
    		Always
    		Below 1 Ω
    E29-40 (AGND) - E18-8 (AGND)
    E29-30 (VC5) or E18-14 (VC5) - Body ground
    		Always
    		10 kΩ or higher
    E29-40 (AGND) or E18-8 (AGND) - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.REPLACE ENGINE SWITCH

  1. for 1GR-FE

    1. Temporarily replace the engine switch with a new one (Click here).

  1. for 1UR-FE

    1. Temporarily replace the engine switch with a new one (Click here).

  1. for 1VD-FTV

    1. Temporarily replace the engine switch with a new one (Click here).

  1. for 3UR-FE

    1. Temporarily replace the engine switch with a new one (Click here).


NEXT


3.CLEAR DTC

  1. Clear the DTCs (Click here).


NEXT


4.CHECK FOR DTC

  1. Check for DTCs (Click here).

    OK:
    DTC B278A is not output.


NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK

END (ENGINE SWITCH IS DEFECTIVE)