Inspection Procedure 2

Inspection Procedure 2: The ignition key cannot be registered using scan tool.

TECHNICAL DESCRIPTION (COMMENT)

If only some ignition keys cannot be registered, the ignition key itself may be faulty.
If no ignition key can be registered, the key assembly may have already been registered for another vehicle, or the WCM may be faulty.

TROUBLESHOOTING HINTS

- Malfunction of the ignition key
- Damaged wiring harness and connectors
- Malfunction of WCM
- Ignition key registered for other vehicle

DIAGNOSIS

Required Special Tools:

- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Check the ignition key inserted in the key cylinder for interference.

Q. Are there other ignition keys or anything that interferes with the communication (things that generate radio waves such as magnets and an air-cleaning device that has a power plug) near the ignition key inserted in the key cylinder?

YES Move away or remove other ignition keys or things that interfere with the communication
(things that generate radio waves such as magnets and a air-cleaning device that has a power plug) near the ignition key. Then, go to step 2.
NO Go to Step 3.
STEP 2. Retest the system

Check that the ignition key can be registered.

Q. Is the ignition key that cannot be registered using scan tool?

YES Go to Step 3.
NO The procedure is complete.
STEP 3. Check which ignition key cannot be registered.

Q. Can any one of the ignition keys be registered?

YES (Only some keys) : Replace the key that cannot be registered and register the ID codes (Refer to ID registration procedure manual - ID codes registration judgement table). After registering the ID codes, go to Step 5 .
NO (All keys) : Go to Step 4.
STEP 4. Retest the system

Check the scan tool screen when the key was not able to be registered.

Q. Is the error message of scan tool screen "Abnormality in key" ?

YES (Abnormality in key) : Carry out DTC B1A25: Key ID unmatched and DTC B1A35: Transponder read error (Refer to Wireless Control Module (WCM) [B1A25], Wireless Control Module (WCM) [B1A35]). Then, go to Step 5 .
NO (ECU internal error) : Replace WCM and register the ID codes (Refer to ID registration procedure manual - ID codes registration judgement table).
STEP 5. Retest the system

Check that the ignition key can be registered.

Q. Is the ignition key that cannot be registered using scan tool?

YES Replace WCM and register the ID codes (Refer to ID registration procedure manual - ID codes registration judgement table).
NO The procedure is complete.