Car initially started first press as usual.

When I turned on the heated front screen, rear screen and fan there was a momentary blip  (misfire perhaps) of the engine, but then ran it normally.

When reversing across my carpark the engine cut out and wouldn't restart. 

Quickly took a look at Forscan and it's showing codes I've not seen before.

Any suggestions would be appreciated. Will check the fuses first.

Nb. The P0420 code was already known. Battery ok. Fuel level ok.

 

Just did some basic checks of connectors, earth points, fuses in the engine compartment all ok.

12v checked ok at F33 location (ignition coils).

All other electrical equipment, headlights etc ok.

Battery voltage ok and still turning engine over as normal.

No sign of firing on any cylinder.

Too cold and wet to tinker around too much. I need a plan to isolate the problem.

11 minutes ago, RayC333 said:

I need a plan to isolate the problem.

I have the Ford wiring schematics for the Focus 2011 and the 2014 if they would be of any help ?

Just let me know if you need them.

Just now, unofix said:

I have the Ford wiring schematics for the Focus 2011 and the 2014 if they would be of any help ?

Just let me know if you need them.

Thanks, but already have them from a previous post of yours.

This thread suggests a bad earth, though a bit vague as to which one.

Ford Focus 1.0 Ecoboost ignition problem after engine rebuild - MHH AUTO - Page 1

2 minutes ago, TomsFocus said:

This thread suggests a bad earth, though a bit vague as to which one.

Ford Focus 1.0 Ecoboost ignition problem after engine rebuild - MHH AUTO - Page 1

Thanks Tom, I saw that thread and although the person confuses the exhaust and inlet side I know which earth point that he means. 

In view of that I'll aim to remove the air induction pipe for access and check it. 

P'ing down here now and no cover in the car park so will report back later.

Unofix, unless I'm reading it wrong, I don't seem to have the correct wiring schematic for the 1.0

Can I please take up your offer so I can be sure.

2 minutes ago, RayC333 said:

Can I please take up your offer so I can be sure.

No problem Ray.

Attached is the pdf file of the Focus 2011 (not an easy schematic to read). Also attached is a download link to the Focus 2014 schematic.

https://drive.google.com/file/d/1-GuVIWeFP7_8Dk_FYYQbyLCIDzHgggZ6/view?usp=sharing

These are the only two schematics I have for a Focus of around your model.

Focus EU_C346 2011.pdf

6 minutes ago, unofix said:

Focus 2011 (not an easy schematic to read).

You kid me not. Every time I think I've found the right scheme, either the fuse numbers don't match or it's got 4 or 5 ignition coils!

Used one of the 2014 sketches to devise a simple earth/ground test at each coil plug. The colour scheme isn't right unfortunately but each of the three wires has an (apparently) good earth connection. Will still check the actual earthing point.

 

Pleased to say the problem is now resolved.

It was indeed the earth connection (location: rear of cylinder head, RH side).

Not easy to access but just about doable with the air inlet pipes removed (section from the air filter box and the crossover pipe) and engine lifting bracket unbolted and moved out of the way.

My magnetic retrieval tool came in handy as kept dropping things down onto the undertray.

It's a mystery to me why it never caused a problem in the months since the engine was fixed - I'll blame the weather 😀