Just come back from a week across the channel. Had problems with the climate control on two occasions.

First, when driving out of a city (Rouen), suddenly noticed that, with the temperature outside at 25 degrees, the fans were pumping out hot air (not at the 21 degrees set) and pumping it out just as fast as they could. Switched on Max A/C and it made no difference.

All the way in to Rouen the car had been pleasantly cool, and I hadn't snagged any obstructions on the underside of the car so I guessed I had a software problem.

Whenever my Microsoft products go a bit haywire I shut them down, count to ten seconds and restart ... so since Sync 2 is a Microsoft product I thought I'd do the same with the Focus, and sure enough, thereafter the a/c worked fine.

Coming back to Calais a day or two later there was a lengthy queue at the peage. About forty minutes crawl, bumper to bumper in the 24 or 25 degree heat. Car was pleasantly cool all the way ... when we got to the peage and my daughter had paid the toll we pulled away fast and there was a blast of hot, humid air ... I asked my daughter to put the window up (thinking it was outside air coming through her window) to which I got, "I have!"

Same problem as Rouen, except this time I was on a motorway ... eventually found somewhere to stop and, again, after a ten second break with the engine off the a/c behaved impeccably.

I have a new diesel Mk 3.5 and will of course take it in to the dealer to look at but thought I would ask if anyone else had experienced the same (software) problem.

Never heard of that before sorry. Keep us posted with what the dealer finds the problem to be.:)

Will do! She's booked in for the 27th ... dealer reckons it might take a long time to track down the source of the problem but I don't think he has heard of anyone else with the same problem.

ac requires cool air to pass through the condensor if the air isnt cool enough ie the car is sitting in traffic its inevitable it will struggle to cool the air down it sounds like it was struggling to cope and pumped out the hot air to clear itself

The traffic in the city was fairly free flowing and the temp was circa 25 degrees (which is pretty typical these days) ... no cause for struggle there ... the problem on the motorway only occurred when I moved away from the peage ... and it took us 5 - 10 mins to find somewhere to pull over so plenty of air was passing thru the condenser!

I reckon software ... but if you turn out to be right, artscot79, I'll be sure to let you know.

If there is insufficient air flow over condensor , thats where the coolant radiator fan comes into play, so whether your staionary or traveling shouldnt make any difference, unless the fan isnt working when required?

Could be interior temperature sensor issue thinking it detecting colder temp than it should, therefore increasing temp of air blown in, quite a few variables can cause this, you could be right on the climate control software though.

I wonder if a temperature sensor might be the cause ... whenever I get in and switch on the exterior temperature often shows a little higher than actual and it settles back a few degrees on driving. But the other day (a baking hot day) I got into the car and was surprised to see the exterior temperature showing as 12 degrees on starting up ... this was the first time I noticed this was distinctly lower than actual ... as I drove off this rose steadily to 24 degrees which is what I expect it was give or take.

Thanks for the input, iantt - I'll tell the dealer about this one odd reading when I take the car in. Although I can confirm that when we had the problem in both cases the exterior temperature was showing what I thought it should.

Well I've taken my car in for a check-up (had to leave it all day) when it was connected up and "interrogated" ... poor little car ... I checked it later for signs of torture but found none.

Anyway, the on-board system would not admit to any faults so come the end of the day the service team drew a complete blank. Despite all the so-called technology in the car they had to admit the only way they'll solve this is if I bring the car in to them while it is actually blowing hot and humid air (instead of cool and dry). Chances of that? In reality, one in a thousand ... no better!

One wonders why bother to have any technology ... I was able to give them precise timings but was told that information was a waste of time. So clearly there is no on-board logging system or if there is, it is completely inadequate.

Perhaps a case that Ford are "kidding us" that things are improving when the reality is they are still ... just Fords ... but with pretty (if somewhat unresponsive) screens!

Oh well, still enjoy driving the car when I'm not being boiled alive.

Ford seem to be pretty poor with fault logging, I've owned many Peugeots and VWs before, both of those log faults and give parameter measurements better than the Fords seem to! And of course the fault readers are only as good as the loggers!

I don't know if you have already but make sure the engine fan comes on when it should (usually constantly with air con on). Seems odd that a restart solves it though, maybe the climate system is just getting confused as you said earlier, if that's the case, the only hope of a fix is a software update.