Mk2 Focus ST air conditioning problem

[m444ttb]

Wondered if anyone could lend their thoughts to what could be up with the A/C on my wife’s 2006 ST3. We’ve found the A/C will blow ice cold when you start the car and run fine for about 15 minutes then it cuts out. The switch remains illuminated but it’s as if you’ve turned it off. If you do then turn it off and leave it for 10mins you get it blowing cold again for maybe another 10 mins before it cuts out again. Repeat ad infinitum.

We took the car to Halford for a free gas check and they said it was ok and no point topping up. It went to the local Ford dealer today who found the same issue (they let it run outside for 15 mins then it cut as they drove it into the workshop). They found there was 300g of gas in the system (works from 250g up apparently) so removed that and refilled with 600g. Checked for leaks etc and none found. They also checked to see if any electrical faults were present and none were found.

So all good and the car was sent on it’s way. Naturally it cut out before we got the car home. It’s going back on 17th but wanted to see if the brains of PH had any thoughts. The issue appears consistently and I’m wondering if there’s a sensor issue (but not showing on diagnostics) or an issue with the compressor (overheating perhaps?). Whatever it is it causes the clutch mechanism to disengage.

[haggishunter]

Low gas would make it go on and off again quite quickly so it isn’t that. Check the fan is coming on to cool the condenser, if it isn’t coming on it’ll sense high temp and switch off to save the compressor.

[m444ttb]

That makes sense. I’ll put that forward to the Ford technician. The same guy is meant to be looking at it and having gone over what he has looked at so far that wasn’t on the list. Would that be an issue at speed still? Or when the engine fan (if they aren’t one and the same) wouldn’t be running?

[Maxrebo]

I had this on my ST it was the compressor their is a magnetic plate and the spring gets weaker over time they out out a spacer and cleaned the plate up which cured the problem

[Howard-]

Condenser fan not kicking in, partially blocked condenser, or weak compressor clutch would be my guesses.

[Emeye]

I am having a similar issue with the aircon on my XC90 - if you turn the aircon off for 5 mins, it may come back on again.

This is a common thing on an XC90/Volvos in general, and is a problem with the aircon clutch overheating - my 2003 Volvo uses a lot of Ford parts, so it could even be a similar model. There is a bread clip / zip tie bodge fix, or you can take it apart and adjust the clutch with shims. Depending on the access, this may be possible to do with it still n the car to save you having to regas the system. I think you can take it off and have it refurbed or even buy a replacement.

I can imagine that under the bonnet is pretty crammed on a Focus ST.

[Podie]

This is what gets brought up on the Focus ST forums...

[m444ttb]

The car was back at Ford today. My wife collected it but they’re fairly hopeless at giving any information anyway. So all that has come back is ‘needs a new compressor for £815 fitted’. Naturally I’ll be looking at the alternatives. Not least as it’s less of a problem on cooler days as it takes longer before it begins cutting out and you don’t feel hot in the cabin once it has initially cooled it down (which it never fails to do). It’s only when it’s over 20degC you begin to notice there’s an issue.