Inspection Procedure 2

Registering the Ignition Key is Impossible.

TECHNICAL DESCRIPTION (COMMENT)
The transponder built-in ignition key or the immobilizer-ECU is suspected to be defective.

TROUBLESHOOTING HINTS
- Malfunction of ignition key
- Malfunction of immobilizer-ECU.

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: MUT-III USB Cable
- MB991911: Main Harness B (Vehicles without CAN communication system)

STEP 1. Using scan tool MB991958, read the diagnostic trouble code.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool.

Use scan tool MB991958 to check if DTC 11 is set.




1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch "ON" position.
3. Read the immobilizer system diagnostic trouble code.

Q: Does DTC 11 reset?

YES: Refer to DTC 11.

NO: Replace the ignition key that cannot be registered. Then re-register the encrypted code (Refer to How To Register Encrypted Code). Verify that the ignition key can be registered, then Go to Step 2.

STEP 2. Recheck for malfunction

Q: Is a malfunction eliminated?

YES: This diagnosis is complete. (If no malfunction are not found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.)

NO: Replace the immobilizer-ECU.