When replacing the ECU, always
check that the communication circuit is normal.
DIAGNOSTIC FUNCTION
If KOS-ECU receives the keyless operation key low battery voltage signal, KOS-ECU sets
the diagnosis code No. B1A10, B1A11, B1A12, or B1A13.
JUDGEMENT CRITERIA
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.
PROBABLE CAUSES
Malfunction of the keyless operation key battery
Malfunction of the keyless operation key
Malfunction of KOS-ECU
DIAGNOSTIC PROCEDURE
STEP 1. Replace the battery in the keyless operation key
and recheck the diagnosis code.
Replace the battery of the keyless operation key for which the diagnosis code is set,
and check whether the diagnosis code is reset.
(1)Replace the battery of the keyless operation key for which the diagnosis code is
set.
(2)Erase the diagnosis code.
(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 diagnosis code is set.
Q.
Is the diagnosis code set?
Go to Step 2.
The diagnosis is complete (Discharged battery).
STEP 2. Replace the keyless operation key and recheck the diagnosis
code.
Replace the keyless operation key for which the diagnosis code is set with a new one,
register the encrypted code and keyless operation key ID (refer to ),
and check whether the diagnosis code is reset.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from the LOCK (OFF) position to the ON position.
(3)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace KOS-ECU and register the ID codes (Refer to ).
The diagnosis is complete (Discharged battery).
),
and check whether the diagnosis code is reset.