Keyless Operation System (KOS)

DTC B1A24: Key ID not registered

CAUTION:

- When the DTC B1A24 is set, be sure to diagnose the CAN bus line.
- When replacing the ECU, always check that the communication circuit is normal.

DTC SET CONDITION

KOS-ECU sets the DTC B1A24 when the key ID was not registered in it.

TECHNICAL DESCRIPTION (COMMENT)

KOS-ECU determines that the abnormality is present, if the key ID is not registered in it when the power supply mode of the engine switch is turned ON.

TROUBLESHOOTING HINTS

- Key ID not registered
- Malfunction of the keyless operation key
- Malfunction of KOS-ECU

DIAGNOSIS

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.

(1)
CAUTION:
To prevent damage to scan tool (MB991958), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (MB991958).

Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."

(2)Turn the power supply mode of the engine switch to ON.

(3)Diagnose the CAN bus line.

(4)Turn the power supply mode of the engine switch to OFF.

Q. Is the CAN bus line found to be normal?

YES Go to Step 2.
NO Repair the CAN bus line CAN Bus Diagnostics Chart).
STEP 2. Register the key ID and recheck the diagnostic trouble code.

Register the key ID and keyless operation key ID of the keyless operation key by which the DTC is set (refer to ID Codes Registration Procedure), and recheck if the DTC is set.

(1)Turn the power supply mode of the engine switch from OFF to ON.

(2)Check if the DTC is set.

Q. Is the diagnostic trouble code set?

YES Replace KOS-ECU and register the ID codes (Refer to ID Codes Registration Procedure).
NO The procedure is complete.