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Discussion Starter #1
Back to the forums with another query...

When I start my car and switch on the air con, the air con runs really cold.

After about 15 minutes of driving it stops blowing cold. Consequently the speed of the blower gets faster because the system is trying to cool down the cabin temperature. But it never comes cold again.

The only way to get the air con to run cold again is to stop the car, shut it down (engine off, ignition off), and then re-start the engine. Then hey presto the air con runs cold again!

I just wondered if this is because it’s a self protection “feature” or if something else is wrong? It's annoying having to keep "rebooting" your car to get the air con running cold again!

Thanks
 

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It could be slightly low on gas.

When air con systems get low on gas they shut down the compressor which means no air con.

Get it checked and see what they say.
 

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Discussion Starter #3
Thanks mikesmith2

Had the system re-gassed today at Kwik-Fit. The mechanic said it wasn't low on gas but thought the gas might be old. Anyway...

Still does the same thing!

When it's working, if you press the aircon button on and off you can hear something kicking in, in the engine bay, and an extra fan comes on. And then off when you press again.

If you leave things running until it stops working, pressing the air con button makes no difference - i.e. no noise changes.

It's almost like there's a solenoid or something which usually works which stops working. That's my completely non-technical view!

It's just a bit weird that after shutting down the engine and ignitition, then starting the engine again, it behaves perfectly. That's what made me think it might be an overide somewhere stopping it from working.

Any other ideas or is it time to book in?

Thanks again
 

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that your aux fan kicking in when the air con is switched on. It also could be your ac pressure switch which might be playing up its located behind the drivers side headlights. Get fault codes read see what comes up. Or you could just change the pressure switch its about £50.
 

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Discussion Starter #5
Car is going in on Thursday to have any faults read. Will get back with results.

However the air con has been running fine this last few days and it hasn't been as hot outside. So I'm thinking it may be some kind of self protection mechanism to stop the coolant boiling.
 

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Discussion Starter #6
Had the air con system checked over by a specialist today and guess what - they could not find a fault!!
 
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