Air-Conditioner Problem

[remigi]

Hi Guys

I had an accident in Dec 2012 where part of the front of my car was damaged. Since then i have had problems with the AC; however, since the compressor was not 'physically' damaged during the accident and the condenser only slightly dented the insurance company is refusing to fix it. The condenser has been pressure tested and has come back fine and so they will not replace it.

The problem I am having is that when I turn on my car and its in idle, if I turn on the AC the compressor will not kick in and therefore there will not be any cold air until I rev the engine to at least 3000rpm for 5 seconds. Once I do that the compressor kicks in and the air starts to get cold. However, I have also noticed that at traffic lights when the car is idling the compressor will stop and warm/humid air will start coming out of the vents until I either start driving again or rev the engine and keep it at approx 3000rpms. The repair shop have re-gassed the AC system; however, this has not fixed the problem. It has fixed this horrible whine/grinding noise that it was making; however, I am still having this idle problem.

Any suggestions on what it could be, or do you guys have this too in your MKV?

[wai]

Make sure that power is getting to the clutch actuator.

Next, Check is that the compressor clutch is engaging.

[Umai Naa!!]

Also worth checking the refridgerant pressure sensor.

[remigi]

Make sure that power is getting to the clutch actuator.

Next, Check is that the compressor clutch is engaging.

I am pretty novice when it comes to cars, is there anyway that I can check this without being a Guru?

Thanks guys

[wai]

I am pretty novice when it comes to cars, is there anyway that I can check this without being a Guru?

Thanks guys

To check for power, you will need a test light (basically a screwdriver with a light in it and a lead you connect to earth). You then need to locate the compressor and check with the test light that it lights up when you touch the power supply contacts. This can be a little daunting, so you might want to leave this to whoever will be looking at it.

You can check if the compressor clutch is engaging by listening for the click as it engages. You will have to have the bonnet open and with the engine idling have someone turn the AC on. You should hear a distinct click as the clutch engages.

Having to rev the engine up to 3,000 rpm is not good as it does indicate that the clutch is having difficulty engaging and then holding.There can be two windings. One to pull the clutch in, and the another (much lower current draw) to hold it in.

It could even be a damaged power lead that is not making proper contact.

It may need to be looked at by someone who understands the ins and outs of the VW unit.