STEP 1. Sufficiently insert the keyless operation key into the key slot, and then check the trouble symptom.
STEP 2. Interference check of keyless operation key when it is inserted in the key slot
STEP 3. Retest the system
STEP 4. Using scan tool MB991958, read the diagnostic trouble code.
Check the DTC is set to the KOS-ECU.(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 too (M.U.T.-III)
."
(2) Turn the power supply mode of the engine switch to ON.
(3) Check if DTC is set.
(4) Turn the power supply mode of the engine switch to OFF.
Is the DTC is set?
Refer to diagnostic trouble code chart . Go to Step 5.
STEP 5. Using scan tool MB991958, read the other system diagnostic trouble code.
Check the DTC is set to the OSS-ECU.(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 too (M.U.T.-III)
."
(2) Turn the power supply mode of the engine switch to ON.
(3) Check if DTC is set.
(4) Turn the power supply mode of the engine switch to OFF.
Is the DTC is set?
Refer to diagnostic trouble code chart . Go to Step 6.
STEP 6. Check which keyless operation key cannot be registered.
Can any one of the keyless operation keys be registered?
(All keys) :
Go to Step 7.
STEP 7. Retest the system
Check the scan tool screen MB991958 when the key was not able to be registered.Is the error message of scan tool screen "Abnormality in key" ?
(Abnormality in key) :
Carry out DTC B1A25: Key ID unmatched (Refer to ). (ECU internal error) :
Replace KOS-ECU and register the ID codes (Refer to ).
STEP 8. Retest the system