Relay 109 replaced still have a stopping problem

[dandia]

Hi Further to my post earlier I have replaced the 109 relay as it felt the right and simplest place to start after reading the forum....thank you. ..... but I still have a problem.
It started Tuesday evening. Drove for about 5 minutes and the car died as I was turning left, I managed to bump it up a kerb and glided to a stop. The only light on was the battery light. Car would turn over but not fire. So I left it. Went back the next morning and it started!. Drove it around for 15/20 minutes no problems. Looked on the internet, spoke to a friend who suggested a key problem and realized I had used an old key so put the problem down to that.
Saturday went out in the car and had exactly the same problem, went round a corner car died I glided to a halt. This time whilst I was sat in car cursing, the car locked itself. Then the alarm went off. (Because I was sat in it?)
So pushed the button to stop it and got out the car, locked it and walked home.
Went back Sunday. No go. Turning over no fire.
Went back today with the aim to phone the breakdown guy from the breakdown, tried the car and it started. So drove it home.
Did some searching (thank you, to all previous posters) and found about the 109 Relay. So changed that.
Car started first turn. Left it running, it ran for about 10 minutes then shut itself off. Now it won't start again.
So what next? Things that may be relevant. We've run low on diesel twice in the last 5 weeks. The car on a couple of times has had a struggle to start. The wing mirrors folded themselves in after the first stall.
I've done some more looking around the forum and come up with these
Could it be sludgy jelly stuff in the filter of the fuel pump?
Change relay 53?
Is it the cam(?) something sensor? I read the post but can't find it now!
Why does the car start after being left stood for a period of time?
All help welcome.
Thank you in advance
Debbie

[bouncypete]

It could be dozens of things but as you say the doors locked and the alarm went off, then on another occasion the mirrors folded, it seems like the immobilizer is being triggered.

The door wiring looms are well known to causes all sorts of weird and wonderful issues due to broken wires and short circuits. This won't explain why it starts after its been left a while so I may very well be completely off track with this suggestion but I wonder if a door wiring fault could be triggering your immobilizer.

https://www.fordmpv.com/smf2/ford-galaxy-common-faults-and-problems/ford-galaxy-repairing-broken-door-wiring/

[dandia]

Thank you. Whilst doing the relay yesterday I did notice that the gaiter is badly split and wires were exposed so I think this has got to be the next 'repair'. Maybe not today...we'll wait for the snow to melt 
I'll let you know how I get on.
Thanks again