Happy New Year all.
I’m in the southeast and we’ve experienced a cold spell for a few days. It was then this issue first cropped up. Found I could not unlock doors with fob. Manual unlock and car start up w/o problems. By the time I reach my destination fob works as expected (lock/unlocks). But issue arise again when parked overnight (warmer weather now). Swapped battery, even though original tests good. What is causing this?
How old is the car battery?
I would first suspect the switch contacts for the switch that closes and operates the door locks. The contacts may be dirty. Especially if you can hear the solenoid operate but the locks don’t move.
Battery about 6mos old.
Only time I hear anything is when the fob is actually working. Am told the driver side window doesn’t auto roll up; have to hold switch (haven’t personally experienced this yet). Also, the knob on door to manually lock/unlock feels loose; not as secure at other ones (at least the rear left one; didn’t tug on the others)
The contacts in the fob may just be worn out. Do you have another one?
Beyond all the other suggestions you may also be nearing the end of the fob battery’s life. It won’t hurt or cost much to replace it.
Might need a little slip and slide on the mechanism.
Fob was replaced and programmed this past spring. Battery recently replaced. Not sure I understand “slip and slide on the mechanism”