Dear Car Talk:
Our 2008 Hyundai Entourage van, which we purchased new, has always had electric door locks that will not function in cold weather. Not sure of the exact temperature, but once winter rolls around, we have to manually unlock the doors; we can't open the locks with the remote. I took it to the dealer when this first occurred, and got some mumbo-jumbo but no solution. I should have been more persistent, but now it is too late. Other than buying warm gloves, do you have any suggestions? -- David
How 'bout a heated garage? Actually, you're lucky that you can't open the doors, David. A lot of Entourage owners from the 2008 era complained that their sliding rear doors would open on their own -- sometimes at highway speeds! I think Hyundai tried to convince those owners that was part of the "James Bond" package.
As for your door locks, there are several possibilities. One is that the linkage itself is getting frozen. Moisture is always present inside the doors, since those cavities are not airtight. So that moisture could be freezing the linkage that connects the "locking button" on the inside of your door to the lock mechanism itself. Is it difficult to unlock the car manually? Or do you see the locks "straining" to open when you press "unlock"?
If so, that suggests that the problem is mechanical; perhaps a bound up or frozen linkage.
In that case, you can have someone remove the inside door panels and spray the linkage with a desiccant, like WD-40. You can try it on one door first, to see if it helps.
Another possibility is that the problem is electronic, and the signal to each door's unlocking motor (solenoid) is not getting through. That could be because of a bad connection somewhere that opens up only in cold weather. We know that wires, like everything else, shrink when they get cold, right, David? If you don't believe things shrink when they get cold, check the next time you go swimming in the ocean.
So it could be a random wiring or connection problem, or there also could be something wrong with the body-control module, which is a computer that operates things like the power door locks.
If absolutely nothing happens when you hit the "unlock" button, and you can manually unlock the doors with no more effort than usual, that would suggest that something more central and electronic is causing the problem.
If it's mechanical, it's probably worth trying to fix. If it's electronic (and there were a number of issues with this vehicle's electronics), you'll have to decide if you're willing to pay a mechanic to try to track it down. And then compare that expense to the cost of a heated garage. Good luck, David.