I'm sure that most of us have experienced the non-locking or non-unlocking doors. You press the button on the remote and hear the door lock actuator engaging but nothing happens. You would need to press the remote button a few times before the lock actually moves. The following is my solution to the problem. It should cost you less than $10 in materials and requires the following tools: flat and phillips screw drivers, 10mm and 12mm socket wrench, little bit of double sided tape, soldering iron and some lube/grease.
You would need to purchase 2 of the following motors (one for each door):
http://www.skycraftsurplus.com/smallflathobbymotor6-24vdc.aspxwww.skycraftsurplus.comItem Number: SK4113
Mfr: Mabuchi Motors
Mfr P/N: FK-280PA-1511A
You will need to either buy or steal 2 of the cheapest BIC clic pens from work, like these:
http://www.amazon.com/Clic-Retractable-Medium-Point-Black/dp/B00006IE7Z/ref=sr_1_2?ie=UTF8&qid=1383189373&sr=8-2&keywords=Bic+Clic+Stic+Retractable+Ball+Pen%2C+Medium+Point+%281.0+mm%29%2C+Black%2C+12+PensOr better yet go to the nearest TD Bank and take 2 of their pens which are readily available for the taking. Again, you will need 2, one for each door.
Now, lets take apart the door. The following pictures are from the passenger side door. (All descriptions are for the pictures that follow the said description)
1st you'll need to take off the door trim. You can see the plastic clip in the following picture. There are 2 more plastic clips were the blue arrows are pointing. Red arrows point to the 3 screws that need to be taken out. Once all is free you will need to pull on the bottom of the door trim to disconnect the clips and then it slides up and off.

The 2 clips as seen from the side of the door. These are the same ones pointed out by the blue arrows above.

The 2 hidden screws inside the door pull.

The screw behind the door lock

You will need to pull on the door lock to remove the black trim behind it

Ones the black trim comes off it reveals a screw behind it. We will deal with it later.

Once the door trim is off, the only thing holding it is the connection to the BOSE tweeter. It's an annoying one, but it is possible to disconnect at the marked location.

This is what the door looks like once the trim is off. Next we need to remove the screw marked with the arrow and the plastic barrier. I would highly recommend wearing disposable gloves when removing the plastic barrier as the black stuff that holds it in place will stick to everything. My method is to go slow, pull on the plastic while cutting the black stuff that will stretch between the door and the plastic with your finger. If you do get that back stuff over something that needs to be cleaned, use lighter or charcoal fluid to clean it up. Works like a charm. Also, if you need to replace that black stuff, you can buy rolls of it on amazon:
http://www.amazon.com/gp/product/B000PEZ1L4/ref=oh_details_o02_s00_i01?ie=UTF8&psc=1
Once the plastic barrier is off, this is what the door looks like

Next we need to remove the window. To do so, raise the window up until you can easily see and remove the window stoppers marked on the following picture

Phillips head screw driver should make an easy work of it. Once the stoppers are out it should look like so

Next raise the window some more until you can easily access and remove the 3 screws attaching the windows to the motor. They are marked in the following picture

Once you remove the 3 screws, just lift the window out from the door. Place the glass somewhere safe. The marked green window guide will need to be cleaned and re-lubed for proper window operation later

Next remove the Styrofoam block attached with 10mm nut and double sided tape

Next you need to remove the window guiding rail, marked with the blue arrow. It is held in place by two 12mm nuts as marked with the red circle and red arrow

The bottom 12mm nut as seen from the bottom

Once the rail is out, you can disconnect the 3 plastic clips holding the door lock cable down as well as disconnect the lock actuator electrical connection and the metal clip holding down the wires

Next you need to remove the 3 screws which attach the locking mechanism to the door. They can be hard to remove, but will eventually come loose

Now the only thing holding the door locking mechanism are two rods attaching the mechanism to the actual lock. They are attached via plastic clips which are really easy to push open. You can see one of the 2 clips in the following picture

Close up look at the top clip. This specific one needs to be pushed towards you to unclip

The 2nd clip. To release the metal rod, you need to push the clip in the direction of the arrow (to the left). Use a flat blade screw driver for extra push

And the clip will come loose

Once those 2 rods are free, you should have nothing in your way to remove the locking mechanism from the door. No fuss, no cursing

Locking mechanism out. To remove the actuator, you will need to remove the 2 marked screws and one more rod connected with the same type clip as above

Door locking actuator is out. Next we need to disassemble it. It is held together by 6 screws as marked. NOTE the position of the rod as marked with blue arrow. Actuator can be re-assemble with the rod in 2 positions. Only one of them is the correct one and only the correct position will make your door work

Again, note the position of the rod before you disassemble the actuator. The correct position is shown below

The insides of the actuator. Finally at the root of the problem. Everything just pulls out

The parts as labeled: 1) gear assembly 2) actuator spring 3) motor 4) capacitor soldered to the motor. Remove the black gear off the motor with a flat screw driver

New vs Old motor. They are virtually identical. You will need to resolder the wired from the old motor to the new one. Note the polarity of the old motor as soldering backwards will make your door unlock when you press the lock button

To quickly figure out which post of the new motor corresponds to the post of the old motor, position both motors side-by-side with the plastic notches in the motor casing facing you as seen in the picture. Now just transplant the wires over to the new motor. Do not reuse the capacitor, it is not needed

Once the wires are transplanted, reattach the black gear to the new motor. With the motor transplant complete, we just need to replace the super stiff and long spring which was inside the actuator. This is were the pens come in. Pick your poison, BIC vs TD Bank. I chose the TD Bank one

Remove the spring from your intended pen and replace the original spring in the actuator assembly. Picture shows the 3 different springs: 1) original actuator spring, 2) BIC pen spring, 3) TD Bank pen spring. TD Bank spring is a little stiffer than the BIC one, but it has less coils. Both work well

Reassemble the actuator and don't forget to grease up all the moving parts. Note the position of the rod, same as it was before disassembly. Note the new spring and note the lack of the capacitor on the new motor

Don't forget to lube all the moving parts inside the locking mechanism before you re-install it back in the door. Check the door lock for proper function. Love the new stronger locking and unlocking thud of the latch. Reassemble the window and door trim in the reverse order.
Simple and cheap fix to the crappy door lock actuator that comes from the factory. Good luck and email me with any questions.
- Vlad