B2784

THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM: B2784: Antenna Coil Open / Short
B2784 - Antenna Coil Open / Short

DESCRIPTION

When an open or short circuit is detected in the transponder key amplifier coil built into the power switch, the certification ECU (smart key ECU assembly) stores this DTC. This DTC is also stored as a past DTC.





* *: Only output while a malfunction is present.

Vehicle Condition and Fail-safe Operation when Malfunction Detected





Related Data List and Active Test





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Before replacing the certification ECU (smart key ECU assembly), refer to Registration Engine Immobilizer System.
* The certification ECU (smart key ECU assembly) outputs a fixed 5 V power source voltage through a resistance from terminal CODE. The power switch grounds or does not ground this power source voltage accordingly.
* The certification ECU (smart key ECU assembly) outputs a fixed 5 V power source voltage through a resistance and transistor. The power switch grounds or does not ground this signal accordingly.
* After performing repair, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

PROCEDURE

1. CLEAR DTC

(a) Clear the DTCs Engine Immobilizer System.

NEXT -- Continue to next step.

2. CHECK FOR DTC

(a) Perform the operation that fulfills the DTC output confirmation operation.

(b) Check for DTCs Engine Immobilizer System.

OK:

DTC B2784 is not output.

NG -- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER SWITCH)

OK -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

3. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - POWER SWITCH)

(a) Disconnect the H1 ECU connector.

(b) Disconnect the H78 switch connector.

(c) 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.

4. REPLACE POWER SWITCH

(a) Temporarily replace the power switch with a new or known good one Removal.

NEXT -- Continue to next step.

5. CLEAR DTC

(a) Clear the DTCs Engine Immobilizer System.

NEXT -- Continue to next step.

6. CHECK FOR DTC

(a) Perform the operation that fulfills the DTC output confirmation operation.

(b) Check for DTCs Engine Immobilizer System.

OK:

DTC B2784 is not output.

NG -- REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Removal

OK -- END (POWER SWITCH WAS DEFECTIVE)