Keyless Operation System (KOS)

DTC B1A10 Keyless/KOS key 1 low battery
DTC B1A11 Keyless/KOS key 2 low battery
DTC B1A12 Keyless/KOS key 3 low battery
DTC B1A13 Keyless/KOS key 4 low battery

CAUTION:
When replacing the ECU, always check that the communication circuit is normal.

DTC SET CONDITION

If KOS-ECU receives the keyless operation key low battery voltage signal, KOS-ECU sets the DTC B1A10, B1A11, B1A12, or B1A13.

TECHNICAL DESCRIPTION (COMMENT)

- B1A10: If KOS-ECU receives the keyless operation key 1 (the first keyless operation key registered with KOS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.

- B1A11: If KOS-ECU receives the keyless operation key 2 (the second keyless operation key registered with KOS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.

- B1A12: If KOS-ECU receives the keyless operation key 3 (the third keyless operation key registered with KOS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.

- B1A13: If KOS-ECU receives the keyless operation key 4 (the fourth keyless operation key registered with KOS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.

TROUBLESHOOTING HINTS

- Malfunction of the keyless operation key battery

- Malfunction of the keyless operation key

- Malfunction of KOS-ECU

DIAGNOSIS

STEP 1. Replace the battery in the keyless operation key and recheck the diagnostic trouble code.

Replace the battery of the keyless operation key for which the DTC is set, and check whether the DTC is reset.
(1)Replace the battery of the keyless operation key for which the DTC is set.

(2)Erase the DTC.

(3)Turn the ignition switch from the LOCK (OFF) position to the ON position.

(4)Lock or unlock the keyless operation key.

(5)Check if the DTC is set.

Q. Is the DTC set?

YES Go to Step 2.

NO The procedure is complete. (Discharged battery)

STEP 2. Replace the keyless operation key and recheck the diagnostic trouble code.

Replace the keyless operation key for which the DTC is set with a new one, register the encrypted code and keyless operation key ID (Refer to ID registration procedure manual - ID codes registration judgement table), and check whether the DTC is reset.
(1)Erase the DTC.

(2)Turn the ignition switch from the LOCK (OFF) position to the ON position.

(3)Check if the DTC is set.

Q. Is the DTC set?

YES Replace KOS-ECU and register the ID codes (Refer to ID registration procedure manual
- ID codes registration judgement table).

NO The procedure is complete.