Disabling Unlimited Key Mode

2010 Mercury Mariner Hybrid, AWDSECTION Disabling Unlimited Key Mode
WARNING: This page is about a different car, the 2005 Mercury Montego, 2005 Ford Freestyle, and 2005 Ford Five Hundred. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: By disabling the unlimited key mode with a random 8-digit number the previous access code no longer operates the vehicle.
  1. Using a diagnostic tool, select PCM from the menu. Select SECURITY ACCESS to obtain security access. For additional information, refer to ANTI-THEFT SECURITY ACCESSΒ .
  2. Select: DISABLE UNLIMITED KEY MODE.
  3. Select: PROGRAM UNLIMITED TRANSPONDER SECURITY KEY.
  4. Enter an 8-digit random number (not 00000000 or 00000001).
  5. Select: IGNITION KEY CODE ERASE.
  6. Disconnect the diagnostic tool and turn the ignition key to OFF.
  7. Program 2 keys to enable the vehicle.
  8. Program any additional keys using either Key Programming Using Two Programmed KeysΒ  or Key Programming Using Diagnostic EquipmentΒ .
RENDER: 1.0x

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