Hi. There is a definite line up the centre of the front screen - clear on one side and fogged the other. Will deffo check the wire as quite a few people have mentioned this. Thanks Peter

Just an update. Had an auto electrician out. Within 5 mins he had found that the earth lead at the top of the tailgate was faulty. It had snapped in the rubber casing.... the only way you could tell it was broken was by pulling the cable and it stretched !!! He has ordered a new one and we agreed to see what effect this has (he picked up on this as one of the other faults was the radio started hissing when the heated rear screen was on....

Thanks for the update mate, always good to hear what's happening with different faults.

OK, a further update. The auto electrical 'expert' has fitted the earth cable on the tailgate but it hasn't made any real difference. He also fixed the heated screen problem (loose connection at the screen).

He took the car away (for a week) and removed and refurbished the alternator as he said it wasn't pushing out sufficient charge. When he brought it back he sheepishly said that whilst he had fixed the output the warning light was still on but the heated seats were working. It was late on a Friday during one of our big storms so I didn'r check - guess what the heated seats weren't working!! Called him and he said he was 'at a loss'. So £ 190 later it's pretty much in the same state as when I started!!! He 'think' it might be the engine management board - but to be honest I've lost confidence in him.

Any ideas - anyone ???!!

Have you properly checked the earthing (body end, not battery end, and the earth cable itself) as per my post of 19/1? Several people have had problems with this corroding, resulting in various electrical problems. IF the alternator (and regulator?) is 'now' OK, and IF the battery is OK it only really leaves the wiring, as I find it hard to believe that something is continuously pulling sufficient current from a 180A alternator to prevent charging without there being some evidence of it.

What is the voltage at the battery with the engine running now? Is it still low?

Have you checked for any stored fault codes?

Don't start replacing the electronics unless you're sure they're at fault!

Going by the voltages you have posted I would say your battery needs attention first, is it still the original? 
Hung like Einstein, smart as a horse.

According to the original post the battery has been tested and is OK. But I too still wonder, hence the bold 'IF' above!