2006 buick lucerne back doors won't open - 2006 Buick Lucerne

My friend just had this problem and he reached in and pulled the inside door handle back as far as it would go, and then let it go, allowing it to 'snap' back. For some reason this fixed it. We have no idea why. By doing this on one door, both rear door locks freed up and the rear locks are now working. Before, both rear locks were stuck and you could not open the doors from the inside nor the outside. Not sure why it works, but maybe it will work for you!

If your door isn't opening when you pull the handles it is most likely because the hinge on your actuator is stuck in the open position from the last time you pulled the handle, therefore the cable attached to your handles cannot pull the hinge again to open the latch that is clamped on the door jamb plate.
Here is a video I did showing how I fixed mine.
https://youtu.be/YvXUNHxMB50

I have a 2006 Buick Lucerne back doors won't open from the inside or out what can I do to get them open without spending a fortune

Same thing just happened today on our 2006 Buick Lucerne where the only the back driver side door won't open by pulling the door latch handle from the inside or outside. Quick fix was to pull (don't let go/keep it pulling) the inside door latch (back driver side) from the inside while another person from the front driver side press the lock then unlock button and then release the inside door latch (back driver side). You will be able to open the door now from the inside or outside door latch.

If you mean, wont open from the inside, it is most likely the child safety feature on the door locks. There is a switch inside the door jam to turn them on or off. Some models have a switch on driver's side window/door lock controls to use this feature also.
Please vote! Thanks, Mike