I've had a number of electrical issues since last year.
I've taken it to a garage but they couldn't find the issue. So a list of
the issues:

1. Battery light comes on after 25-30 seconds.
2. Front
passenger central locking doesn't work. If it is unlocked, global
unlocking doesn't work (all locks close and then open, like if you tried
to lock the car when a door was open). Only when it is locked does
global locking/unlocking work with the keyfob.
3. Issues with ignition (car had poor idle, replaced ignition coil - not sure if it was due to electrics).

4. Starting issues (the biggest problem). When I try to start the car
all electrics shut off. I have to open and close the drivers door
several times and turn over before the car will actually start and even then it sounds
like the car might not start. This happens both after leaving the car
overnight and if I switch it off and turn it on after a while (so when
the cars still hot).

5. This just started happening, engine power starts cutting out when I'm driving at low speed!

Attached a link to show 4. http://1drv.ms/1QraVin

1) Battery light will come on if the battery is not charging correctly, or, if the car has Smart Charge, the voltage is probably not being regulated correctly. What year is it?

2) The door module is not connected to the central locking system, or, the locking mechanism is jammed. Try locking just that one door manually, if it locks, then the mechanism is fine, check if you have a fuse per door, if you do, you may find the fuse needs replacing. If the fuse is fine, its probably a wiring issue, that will be fun,

3) Define "Ignition" - are you referring to the act of starting the car, or are you referring to something else?

4) Their are two probably causes here, either the crankshaft sensor is giving a bad reading (wiring, or faulty sensor) or you have a further electrical issue, given issue 1) I would suggest this may be related. The battery probably needs replacing, and I would also clean up the main earth point next to the battery.

5) I think this probably is related to the electrical issue.

Final piece of advice, whichever garage you went too, dont waste your time going back. if they cannot diagnose those issues with the car in front of them, yet I can give you the above without seeing it, then I wouldnt trust them to urinate on my car, let alone diagnose and resolve it!

1) Car is an X reg 2000. Checked battery voltage using a voltmeter: 12.6V when off, 13.4V when idling.

2) Door locks manually, will check the fuses.

3) Ignition - sorry I meant idling. Idle feels rough and like its going to cut out.

4) I think wiring was loose. Tightened it up, it should be OK I think. However, I think the earth cable is frayed or something because of the battery light.

3) If its a 1.8 petrol, check the crankcase breather pipe hasn't split and is sucking in air. May also be the idle control valve. Had to replace both on my mk1 focus this year.

Battery may be faulty 13.4v on idle should be 14v or higher starting and rough running could be idle control valve