Curiosii for ever!: Car repair manuals for everyone.

Inspection Procedure 2

The Ignition Key cannot be Registered.

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

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

Required Special Tools:
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: MUT-III USB Cable
- MB991911: MUT-III Main Harness A (Vehicles with 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 DTC11 reset?

YES: Refer to DTC 11.

NO: Replace the ignition key that cannot be registered. Then go to Step 2.

STEP 2. Retest the system.

Register the ignition key.

Q: Does registered ignition key function properly?

YES: The procedure is complete.

NO: Replace the immobilizer-ECU.