Air Con Vag Com

[marinabrid]

hi all

can anyone tell me which module you ask about faults with the switches to do with the air con, unless anyone else has similar prob, was fine then just dont get cold had a regass everything seems in good order yet still no cold air thanks

[marinabrid]

forgot to mention although everythings gassed up i noticed the compressor noise when it kicks into action isnt as loud and powerful as it used to be. could this be the problem ? is there any other way to test it thanks

[marinabrid]

going mad today forgot also this may help thoses in the know.. all the pipes from the compressor were not cold, the ones up to the bulkhead the fat one was hot and the other warm no condensation or coldness on them is it compressor even though its cliking in albeit very queitly

[matt1003]

got the same problem but if the fans dont switch on when you turn a/c on

it wont get cold ( this is the problem im having ) vag com controller

should be the climatic controller but mine didnt bring any fault codes up !

im going to have a look at the whole car next week so ill let you know

if i can find the problem

matt

[marinabrid]

thanks my fan is running all seems well except no cool air, no leaks, fully gassed , new dryer, but the compressor only clicks queitlwhen turned on although its engaging the clutch and spinning

[matt1003]

did you have it regased at a garage or one of the top up cans ,

if it was done at a garage they should of checked the centre vent tempratures

if the fans come on 10 seconds after the ac is switched on then you

should get cold air threw the only other part of the ac system that

would stop it getting cold would be the dryer as far as i know

( if it doesnt dry the air enough it doesnt flow round the condenser

propley) i know you can do output tests with vag com but has to be registered and

not sure about ac tests ( by the way on vag com its auto havc controller sorry )

matt

[marinabrid]

regassed by a mobile professional known him many years, one odd thing though although the compressor clicking in and turning none of the pipes are cold up to the bulkhead very odd

[MrT]

Possible broken compressor shaft? The compressor centre should turn by hand with a resistance (obviously turn the engine off), if it turns freely the shaft may be broken.

[marinabrid]

when engine off i can turn the compressor inner there is some resistance there it does spin when the engines running why arnt the pipes getting cold ?

[MrT]

Vagcom will only tell you if your pressure (over/under) has been activated and various readings for the climate control sensors and distribution flaps. Whilst the climate control electronics make lots of decisions as to how the air is distributed in the car, the only decision it makes as to the refrigeration operation is compressor engaged or not.

 

If you do not have cooling when the clutch is engaged, either you have lost gas, the compressor is not compressing or you have some other obstruction in the system.

 

A pressure test on only the low side may well show a reasonable pressure when there is in fact too little gas for the cooling system to work. There may be enough pressure for the low pressure lock out not to be triggered. The only real way to tell how much gas you have is to vacuum it out and weight it.

 

When my system failed to cool the car anymore, the low pressure side still gave an adequate reading. A combined high pressure and low pressure test would show if the compressor was working properly, but this needs more than the DIY kit commonly available. When mine had failed it still passed all the leak pressure tests, but still kept on very slowly losing gas at the top of the condenser/dryer which did not show any dye.

 

If yours is an early Mk2, years 2000-2002 the corroded condenser/dryer is very likely the problem.

 

All your symptoms are the same as my failure.

[marinabrid]

does thae fact that none of the pipes are cold mean the compressor is not working right even though its clicking into action ?

[seatkid]

Yes

[marinabrid]

so as i respect your judgement seatkid through many items causing worry or annoyance do you think i should swop the compressor as ive a spare one here doing nothing, what i cant fathom is why the engineer didnt feel the pipes and diagnose , he had a window gauge between two gauges and showed me the green gas in there i dont know

[seatkid]

he had a window gauge between two gauges and showed me the green gas in there

 

Don't know what chicanery this is, R134A is a colourless gas, Might be dye he put in. His gauges doesn't sound like any setup I've seen.

 

 

On the evidence, I would say that the problem lies in the electromagnetic clutch. It may have worn out, or have an electrical problem, or be contaminated with oil - basically the compressor isn't being driven when engaged - the clue being the quiet click instead of the loud clack! On the other hand the compressor may have seized causing the a/c clutch to burn out.

 

Options:

 

1. First check the voltage to the compressor, too low a voltage maybe the reason the clutch is working correctly.

 

2. You could go to kwikfit for an a/con topup @

[marinabrid]

thinks i will do nothing as the summers gone ! the compressor was second hand last year and the guy said then it was a noisy one and may not last, but its done a year even my bodged up pipes are still holding the pressure, just annoying ive had it regassed at Edited July 21, 2007 by motorcareman