I'd say a combination of cold weather and moisture.....not being facetious here....They make lock de-icers you spray into the cylinder that will both cure this and prevent it happening again. Once it's warm out again you can spray a little WD-40 (water displacer) to keep it lubed and from happening again.
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1994 SPi Project Mini
Yea. Tried all that. Have used propellant deicer and it worked for a while but that is even failing.
Because it is chronic thing we found a battery operated heat deicer that he used last night. Like a small lighter with a toothpick sized elec element that you slide into the lock set and that worked.
Everything I've read on locksmith stuff says graphite only on tumblers. That grease or wd40 etc will pull dirt in.
I haven't pulled the panel off this year but did in the past and no obvious rust etc.
Starting to think maybe the mechanism has a helper spring that is rusted and failed maybe. Therefore the fob gets no assistance in turning the latch over. The key would be in the same boat and you are putting all the torque onto that key and cylinder.
2006 R53 | Hyper Blue | 6 speed | formerly belonging to member: http://www.motoringalliance.com/foru...-cooper-s.html
2014 VW GTI Candy White | Drivers Edition | DSG | Leather | Sunroof | Nav | Flappy Paddles
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WD-40 is the kiss of death if you want to keep water out - sure, it 'displaces' water initially but it does that by sucking water into itself, so it will pull water in even from the atmosphere and that can then freeze.
I used to run Italian cars through British salt-laden winters, including a 1980s Alfasud flat-four engine with those long plug leads from distributor to spark plugs, so I claim 'expert' status when it comes to keeping water out of things. Every autumn the plug leads came out of the car, were scrubbed in detergent, dried in the oven, put back on the car and sprayed with ignition sealer (which is just lacquer, or hair spray, really) to keep them working.
Newbies are often told to spray WD-40 on damp ignitions but that creates a bigger problem once the WD-40 has collected moisture and holds it next to the plug leads, so after a day or two, more WD-40 is needed to get the engine to start.
Of course, another 'cure' is not to buy cars with Italian electrics, though they are a lot better these days.
In the days before remotes graphite in the lock cured the problem. But from you've said the remote is having trouble popping the lock which may indicate the problem isn't in the lock but in the assorted linkage.
Unfortunately that means pulling the panel to solve the problem. There are some "dry" lubes out now like the one used for bike chains that don't attract more grime.