Air Con Problem

[neil h]

Vehicle 2003 2.3 Galaxy Zetec Petrol.55,000 miles

Apologies if this problem has been addressed before. Have checked several aircon problem posts but none with exactly the same problem as mine.

My aircon had stopped working so took to my local garage for check/re-gas.

During the re-gas the Mechanic advised that system was overfilled as he took over 1000g out of the system, which is a single system had should have had around 700g.

Vacuum check went ok, but at the FINAL check he noted that no pressure was being delivered. As the undertray was already removed (dripping sump seal but that is another problem)he checked to see if the compressor was operating, which it wasn't. The clutch was not rotating with AC switched on.

He checked the power supply to the clutch which was ok, so has diagnosed either a clutch problem compressor problem or both.

He is getting me a price on monday to decide what i would like to do.

Firstly I am a bit peeved that he didn't check that the compressor was operating at the outset, as I have now forked out

[seatkid]

Double check by check you actually have 12v on your clutch (measure across the connector), you could even try a direct 12v feed to make sure.

 

Its unusual for a clutch to fail electrically. Note there is a 3-way pressure switch that supplies the 12v to the compressor. If its under or overfilled then the pressure switch stops the compressor engaging.

[neil h]

Thanks for your comments. I witnessed the mechanic removing the connector and putting his meter across the terminals thus saving me the job of checking fuses etc. Power supply was ok.

As there is 12v at the connector, does that mean the pressure switch is ok, or could it still be the pressure switch rather than the clutch or compressor.

any help appreciated.

 

thanks all

[chrispb123456]

Just to add to whats been suggested do your cooling fans come on when you switch on A/C? also when you check for voltage at the compressor plug try using a test light just incase that 12 volt drops to zero when connected to compressor.

What area of the south east are you? I know a good mobile aircon man in Maidstone area.

[seatkid]

Thanks for your comments. I witnessed the mechanic removing the connector and putting his meter across the terminals thus saving me the job of checking fuses etc. Power supply was ok.

As there is 12v at the connector, does that mean the pressure switch is ok, or could it still be the pressure switch rather than the clutch or compressor.

any help appreciated.

 

thanks all

That is not a good test - its possible for 12v to be present at a disconnected connector due to leakage (a high resistance) - but not actually capable of supplying sufficient current when plugged in.

 

Check for 12v at the connector when it is actually connected.

[neil h]

Thanks both for your suggestions. Will do both checks at the weekend or earlier if I get chance. The garage have quoted me

[neil h]

Thanks Chris & Seatkid,

 

I have just been under the car to confirm the part number etc and can confirm that the two cooling fans do start up when I switch the aircon on. What does that confirm?

I am just about to try to check for 12v whilst all connected probably by sticking a couple of pins through the insulation then re-sealing unless i can get my probes into the connector. Will let you know in half an hour, then summarise where I am.

thanks,

 

Neil

[neil h]

To summarise:- 2.3 galaxy petrol 2003 reg. 55,000 miles

 

Aircon wasn't working so took for re-gas.

Regassed ok but noted no pressure being delivered during pressure test phase. No leaks on system.

Both fans were cutting in but clutch not driving.

12v confirmed at terminals using meter and test-light.

 

I have resigned myself to fact that will be getting a new unit for

[chrispb123456]

Now you have confirmed you have a good 12 volt supply to the compressor and that the centre part of the clutch is not turning then yes you need to replace compressor.

It will be false economy just to do the clutch on it's own.

 

The pipes running through the wheel arch are prone to corrosion around pipe clips look for any tell tale signs (dye marks)

[neil h]

The guy said that the system held a good vacuum and also had much too much fluid in at the start of the test, so I think it is leak-tight.

 

What are your thoughts in having to replace the drier and expansion valve at the same time, as some of the compressor suppliers say that warranty is invalid if not?

 

Neil

[chrispb123456]

Thing is you have to draw the line somewhere not sure on price of expansion valve but the drier/condenser was

[ghr]

Is it possible to tell if there is any gas in the system and that it is not a faulty switch?

[seatkid]

Take it to Kwikfit - £49 to regas - if it doesn't work or has a leak then it'll cost you nothing - they'll tell you how much was in and leave you with the correct amount in even it doesn't work - unless of course if you've got a leak then the machine will not fill it up. (no cost) Edited June 20, 2011 by seatkid

[neil h]

The starting point to this sorry tale was that I had the system re-gassed, as I had just had my fiesta done successfully. It was on the last part of the re-gas that the mechanic noted that no pressure was being delivered and the clutch wasn't cutting in. See original post. Latest is that I have got a new compressor,

[Barlidge]

Have just changed my condenser/drier due to leakage but at the same time may have uncovered a blockage in the old condenser, I had oily residue and dye on the high pressure side and nothing on the drier side. I am taking to aircon guy tomorrow for vac/regas and see what he has to say, will let you know if anything seems relevant.

 

Do you know if the system has had leak sealer put in at any time?

 

Just to add, I think its unlikely that the drier alone is causing the problem, having disected mine and looking at the contruction it is just a plastic cage in a tube filled with moisture absorbing granules that the gas circulates around. Unless the complete cage collapses then I dont see how that alone can block the system, I can post some pics of mine if it helps.

Edited June 24, 2011 by Barlidge