Hi folks, me again with the highly tempremental Focus. 

This time the boot refused to open. Got it down to a very corroded and broken pin in the boot release mechanism and the connector for it on the loom. Tried attaching a new lock and connector - no dice. Same with replacing the loom for a known good one along with the matching mechanism (I literally watched the guy at the scrappy open the boot and helped to remove the loom and the lock) however the loom from the scrappy has code BV6T 17N400 AGG, the original one in the car has BV6T 17N400 AAJ. Would this make any difference when I'm trying to just get the boot to open, or would I have to plug in all connectors (rear window demist, brake light etc)?

My only remaining thought would be the switch, but that has no signs of corrosion and also the number plate light connected to it still lights up.

I've been chasing my tail about this for the last 2/3 weeks, any help would be appreciated

 

EDIT: in the car originally there are boot looms. BV6T 17N400 AAJ and BAH. BAH has the boot release button on its circuit, and AAJ has the lock on it. Would F1ET 17N400 AAJ and ACH looms be compatible with a 2013/14 focus when they come from a 2015+ model? All the connectors and grounding wires look the same

Hello Rich, the last two letters are the batch/manufacturing date/revision and are of no importance.

Have you checked the BCM part of the fusebox under the glovebox? The boot release is controlled by the BCM which is known to have water penetration  problems on your model

Hi unofix, there's no water penetration from what I can see. It's all bone dry and we've had a fair chunk of rain the last few days. That was where I first checked to see if it was a fuse that had blown. All fuses are fine though. 

The boot isn't opening by the button or by either key fob.

So if I was to get hold of the newer version of the loom, (the f1et version) should that be a straight swap over?

Hello Rich, the wiring loom should be a straight swap but I must admit I don't think it will fix your problem.

The water getting in to the BCM comes from a fault with the design of the screen wash pump. The internal seal of the pump leaks and water gets inside of the actual wire and is then drawn by capillary action through the wire until it ends up inside the BCM connector.

I suspect the actual boot lock switch as being the problem and when faulty can even cause the keyfob button not to work.