Door won't lock on a hot day

[TheMrX]

Hi all

Wonder if anyone can offer any advice on this one please? On a hot day the central locking wont lock the driver door.  Sometimes, if I give it a real hard slam then it may work.  But when its really hot, no amount of slamming will make it work.  It seems to me that some sort of connection or unit is expanding in the heat and stopping something from working.  If I press the central locking button on the remote it just makes the noise like it doesn't.  As soon as it cools down then it works. 

I've done some googling and cant find anyone else talking about the problem so thought I'd try here.

Its a Mk6.5

Any ideas very welcome.

Thanks

[fiestaecoboostman]

Any central locking problem involving the drivers door I would always suspect the wiring loom where it goes into the door. If you pull the rubber wiring cover back and inspect them you can usually see the damage where the opening and closing over the years has taken a toll on the wires. Like you say the heat must be making something expand slightly, but the wiring is the most likely suspect.

Any other cable bent back and forwards repeatedly for years would do the same thing. Its often evident by damage to the insulation but it can be just the copper wire inside that has seperated.Sometimes you can cut out a couple of wires and replace just using bullet connectors, If a few are gone usually better to but a new loom part. Overpriced obviously.

[Bobr]

If it was the wiring loom then surely it would happen regardless of the temperature.

[fiestaecoboostman]

On a 2007 car that's where I'd start looking. i'm struggling to think why its the heat, but when you find the fault it might be apparent. The expansion in a copper wire is going to be very small, so yes, I can see what your saying - but where else would you look?