1999 C70 coupe driver's door lock refuses to engage at times. This includes both the switch and the factory keyless entry remote. Yes you could use the key, but this is just plain annoying.

List of replacement parts needed:
1. after-market door lock actuator (any brand will do, common model is DEI 524N, this is a Directed electronics model, cost is anywhere from 6-20 US. dollars)

2. Relays to power actuator (I used a DEI 451M, this is an inexpensive lock relay that will provide power. Stop by a Best Buy or Circuit City, the install shop should have a box of them lying around. I got this for 1 dollar at Circuit City, probably the only thing that was cheap there =)

Tools needed for install:
1. Flat head screwdriver
2. Phillips head screwdriver
3. Soldering iron or crimp connectors, either method works for connections, you decide which route you want to go.
4. Power drill or electric screwdriver, this includes a small drill bit or a self tapping screw used as a drill bit.
5. Dremel cut off tool, or a hacksaw.
6. Torx screw set
7. Super Glue

First you must remove the door panel, following instructions are for a 99 C70 coupe only, but I am sure you could adapt it to any Volvo with minor modifications.

Removal of door panel:
1. Remove trim piece from back of mirror. Just pull this straight out with your hand, if you want to use the screwdriver to pry it loose, that is ok.








2. Remove small cover located in handle pocket. Underneath is a torx screw you must remove.




3. Remove door panel clips located on bottom of door. Use the flat blade screwdriver to push the center in slightly to unlock the pin, then pry out. They will come out very easily. These are along the bottom and on the door side by hinge.





4. Gently pull bottom of panel away from door this will release bottom clips of door handle bezel. Now gently pry rest of bezel off using the flat head screwdriver. I find this method works best as it does not leave any pry marks on plastic.





5. Remove Phillips screw located on top of door panel by the window. This is located under a rubber seal that will need to be glued back on for re-installation.






6. Pull door outward from bottom releasing all the clips, then lift entire door panel up
from window ledge. You can now start unplugging all the electronics to completely remove panel.






7. Now mount the motor by the door lock. The actuator does not have to be perfectly vertical. Not gonna go into specifics, pictures should be self explanatory. Be careful when drilling into door, there are other components just inside the door. Tap metal to make sure it is hollow where you are drilling into.






Not included is how I bent the connecting rod to go to door lock pin, this will be unique to the installation since each motor will be mounted slightly different.

8. Wire relay , again this is a DEI 451M procedure, if you want to use other relays that is your choice.

Lock wire- Yellow (connect small green wire from relay)
Unlock wire-Brown/Blue (connect small blue wire from relay)
Power wire- Red (connect purple wire from relay)
These are located in the middle of the door.



Connect white/black, brown/black, and small red wire together to ground.



9. Clean up wiring and do final adjustments to lock motor actuator and connecting rod.

Note: you may choose to keep both the factory motor and after market working simultaneously, or just cut the yellow and brown/blue from factory motor. This lock will now work with both the remote and the lock switch.

10. Reverse steps to reattach door panel. This is a cheap fix, cost me 7 dollars and some time. If you have any cheap DIY fixes feel free to add. Please include instructions for others to follow. Good Luck!








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