When the weather gets colder, car doors may get hard to close. Symptoms: the car door not fully latching in the second catch, having to slam the door really hard to get it to close, or the door not closing at all. There are some possible causes: wear and tear of the mechanism, the door lock can be out of adjustment, or the lubrication in the lock is old. On my Peugeot 205 I already fixed the door lock adjustment, so I decided to thoroughly clean the lock and re-lubricate. This guide shows the the passenger side door.

Supplies

Torx screwdriver

Philips screwdriver

Mirror

Old tooth brush

Brake cleaner

Sewing machine oil or equivalent

Water Pump Pliers

Needle nose pliers

Locking pliers

Punch and a hammer

Step 1: Remove the Door Card

Gently pry the bezel around the locking stalk loose in a 45 degree upward motion
Pry the cover of the arm rest and remove two torx screws
Pry away the door latch bezel
Unscrew two torx screws from the speaker cover. Slide forward to remove.
Unscrew the torx screws holding the power window switch and storage tray.
Unplug the power window wire from the switch
Pry the door card loose. It is held with plastic clips that should just pop loose.
Feed the power window wire through the door card.
Put the door card aside.

Step 2: Remove the Locking Assembly

Unplug the power door lock actuator
Remove the locking stalk by rotating the small white clip that holds the rod in place.
Remove the inside door latch by sliding it forward and pulling.
Using a mirror, maneuver the rod that goes to the inside door latch such that it comes undone from the lock assembly. It must be rotated 90 degrees.
Remove the outside door handle rod by rotating the small white clip that holds the rod in place.
Pop off the plastic rotating assembly from the outside door lock (which is controlled by the key).
Unscrew 3 short screws in the side of the door. This releases the door lock mechanism.
Also unscrew the fourth screw in the side of the door which holds the window channel.
Maneuver the lock assembly past the window channel and take it out.

Step 3: Disassembling the Lock Assembly for Thorough Cleaning

The lock assembly is not really made to be serviced, but with a careful application of force can be opened up. Be sure to catch all the springs!

Remove the remote door lock actuator by rotating it.
Using pliers, straighten the two tabs marked in blue.
Slide the plastic cover of. It may need a little bit of wiggling and careful bending because it is still held in by a small trapezoid shaped tab and the edge around the catch. Don't lose the three springs.
Using pliers, flatten one side of the metal where the trapezoid tab falls in. This will aid in reassembly.
Clean the inside of the lock assembly using brake cleaner and a toothbrush. Optionally dry using
Lube all the moving parts liberally with a thin oil or grease like sewing machine oil.

Step 4: Reassemble the Lock Assembly

On the plastic cover: locate the springs such that their ends protrude through the top.
Using a tie-wrap and the locking pliers, keep the catch mechanism under tension and out of the way.
Replace the plastic cover, ensuring the springs locate correctly.
Bend one of the tabs back to keep the cover in place temporarily
Tension the two springs by taking their protruding end with needle nose pliers and rotating them until they fall into the notch.
Insert the third spring in its hole and locate using a screwdriver. Be careful not to launch it across your workshop.
Remove the tie-wrap and locking pliers.
Fully bend the two tabs back into their original position.
Lock the trapezoid tab by indenting the metal we bent in the previous step by using a hammer and punch.

Step 5: Reinstallation ...

... is the reverse of disassembly.

Check your door catch adjustment. The lock assembly should be inline the door catch (ensure the door does not lean on the door catch). Also check that the door gaps are even and the door is snug against the door rubbers (but not too tight, or the door becomes difficult to close again). Loosen the two big torx screws if the door catch needs adjusting.

You should now have a nicely closing door again.