When replacing the ECU, always check that the communication circuit is normal.
DIAGNOSTIC FUNCTION
If KOS&OSS-ECU receives the keyless operation key low battery voltage signal, KOS&OSS-ECU sets DTC B1A10, B1A11, B1A12, or B1A13.
JUDGMENT CRITERIA
B1A10: If KOS&OSS-ECU receives the keyless operation key 1 (the first keyless operation key registered with KOS&OSS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.
B1A11: If KOS&OSS-ECU receives the keyless operation key 2 (the second keyless operation key registered with KOS&OSS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.
B1A12: If KOS&OSS-ECU receives the keyless operation key 3 (the third keyless operation key registered with KOS&OSS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.
B1A13: If KOS&OSS-ECU receives the keyless operation key 4 (the fourth keyless operation key registered with KOS&OSS-ECU) low battery voltage signal in five consecutive times, it is judged as abnormal.
PROBABLE CAUSES
Malfunction of the keyless operation key battery
Battery drain of keyless operation key
Malfunction of the keyless operation key
Malfunction of KOS&OSS-ECU
DIAGNOSIS
STEP 1. Replace the battery in the keyless operation key and recheck the DTC.
(1) Replace the battery in the keyless operation key.
(2) Push the lock switch or unlock switch of keyless operation key.
(3) Check if the DTC is set.
Is the DTC set?
Perform troubleshooting if KOS&OSS-ECU DTC except No.B1A10, B1A11, B1A12 or B1A13 is set. Then go to Step 2.
The diagnosis is complete.
STEP 2. Check whether the DTC is set again.
Replace the keyless operation key for which the DTC is set with a new one, register the key (Refer to ), and then check whether the DTC is set again.
Is the DTC set?
Replace KOS&OSS-ECU and register the ID codes (Refer to ).