Pinpoint Test W: Manual Door Lock Cylinder Inoperative

2010 Mercury Mariner 2WD V6-3.0LSECTION Pinpoint Test W: Manual Door Lock Cylinder Inoperative



Handles, Locks, Latches and Entry Systems







Pinpoint Tests

Pinpoint Test W: Manual Door Lock Cylinder Inoperative

Normal Operation

The door lock cylinder is connected to the door latch via a lock rod and can be used to manually lock/unlock a door.

This pinpoint test is intended to diagnose the following:

- Bent or binding lock rod and lever
- Door lock cylinder
- Door latch




PINPOINT TEST W: MANUAL DOOR LOCK CYLINDER INOPERATIVE

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W1 CHECK THE LOCK CYLINDER OPERATION AFTER LUBRICATION



- Spray a lock lubricant such as Motorcraft XL-1 into the lock cylinder opening for a couple seconds.
- Operate the door lock cylinder with the key.
- Does the door lock and unlock using the door lock cylinder?

Yes
The concern was caused by an insufficiently lubricated lock cylinder. Spray a multi-purpose grease such as Motorcraft XL-5 into the lock cylinder for a couple seconds to provide long term lubrication.

No
GO to W2.

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W2 CHECK THE DOOR LOCK CYLINDER



- Remove the door lock cylinder. Refer to Door Lock Cylinder Service and Repair.
- Operate the door lock cylinder with the key.
- Does the door lock cylinder rotate freely to both lock and unlock positions?

Yes
GO to W3.

No
INSTALL a new door lock cylinder. REFER to Door Lock Cylinder Service and Repair. TEST the system for normal operation.

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W3 CHECK THE DOOR LOCK CYLINDER LINKAGE



- Operate the door lock cylinder while observing the linkage.
- Is the door lock cylinder rod and lever bent or binding?

Yes
REPAIR as necessary. TEST the system for normal operation.

No
INSTALL a new door latch. REFER to Front Door Latch Front Door Latch. TEST the system for normal operation.

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RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.