Air Con

[JoAnn merkur]

HELP HELP HELP Okay I am still searching for the answers of the "Mysterious Aircon" problem. They have done a full computer check on the car and it shows no problem areas at all. Well , some might say this is good. However, the air con still cuts in and out. We have replaced the compressor, but it has not fixed the problem. Is there some one some where who has had the same problem, or is there a contact for emailing the manufacturers?
Getting desperate, hot summer is on the way.
JoAnn

[KennEls]

Originally Posted by JoAnn merkur

HELP HELP HELP Okay I am still searching for the answers of the "Mysterious Aircon" problem. They have done a full computer check on the car and it shows no problem areas at all. Well , some might say this is good. However, the air con still cuts in and out. We have replaced the compressor, but it has not fixed the problem. Is there some one some where who has had the same problem, or is there a contact for emailing the manufacturers?
Getting desperate, hot summer is on the way.
JoAnn

Don't know your exact problem our even if I had similar, I tend to think that Brisbane weather does strange things to Air Con's, but I could probably suggest that maybe you contact Pavilion Motors in Ipswich, they stripped and fixed mine for a reasonable cost.

They also had employed there mechanics who had been trained on SVX and the then owner of the car yard had one. Unfortunately the business was sold about two years ago, but I think one or two of the original staff are still there. (Ray I think was the main mechanics name if that helps)

Kenn

[JDW-SVX]

This may sound like a silly question.........

......but do both cooling fans start when the A/C is switched on, and does their speed change in accordance with the refrigerant pressure?

If the refrigerant pressure (on the high pressure side of the compressor) exceeds approximately 1569 kPa, then the cooling fans should increase in speed.

If it exceeds 2648 kPa, the compressor will shut off.

If the fans are not running, or are running too slowly, then it is feasible that the refrigerant pressure will exceed this limit, and the compressor will shut off until it drops again.

................other than that, I have no idea what could be happening!



Jason.

[Dessertrunner]

Joann,
I am new to the problem so I need more info did this happen after you had the unit recharged. Are we talking about the compressor turning on and off of the fans as I all the feed back is not clear.
Tony

[Earthworm]

So if there are no error codes then it's possible that they are not charging the system properly.

Mine cycles but I know the evaporator temperature sensor is defective because of the error code.

[JoAnn merkur]

Thanks guys,
I will pass on every bit of information I get from you to the aircon expert. They have spent many hours trying to fix it. He also joined this site a few months back for the purpose of helping me.

Dessert runner, the problem is a mystery.The subaru people spent hours with the aircon tech going through the operation.
What seems to be happening is: the aircon comes on and runs for approx. 80 seconds. it turns itself off for approx. another 80 seconds . and we continue in this circle. With the bonnet up, you can actually hear the switch at the compressor click off. The replacement of the compressor was not successful.
They now feel we should try a new interior switch board.I know someone who has a spare, but he is reluctant to lend it to us, for fear of us breaking it.
The temperature does go down to 11 degrees as it should.

JoAnn

[JDW-SVX]

Originally Posted by JoAnn merkur

With the bonnet up, you can actually hear the switch at the compressor click off.

Since we know that the compressor clutch is being repeatedly engaged and dis-engaged, the next step that I would take is to find which device is causing that.

There are three possibilities here - either the Trinary Switch (located on the high-pressure side of the compressor) is tripping due to abnormally high or low pressure. When either of these events occur, the switch will not allow the compressor clutch relay to close. This event cannot be over-ridden by any other system (such as the ECU or climate control computer).

The second possibility is that the ECU could (for whatever reason) not be allowing the compressor clutch relay to stay closed. I am fairly sure that the actual command to activate the compressor clutch comes from the ECU, not the climate control computer. This explains how the ECU can shut off the compressor when the throttle is opened fully, for extra power.

The third possibility is that the climate control computer is (for whatever reason) not allowing the compressor clutch relay to stay closed.

What I would be doing is obtaining a wiring diagram of the ECU and Climate Control system, and working out what wires are causing the signal to the compressor clutch relay to be broken.

I will check my wiring diagram when I get home tonight, but I am almost certain that the climate control computer sends a signal to the ECU, which then sends a signal to the compressor clutch relay. Between the ECU and the relay is the Trinary Switch, which breaks the connection if the pressures are too high or low.

Jason.

[Dessertrunner]

JoAnn
I once had a problem with my unit and it turned out to be to much gas apprantly it causes the unit to switch of and on, suggest you get them to remove osme of the gas and see if the duration of on off changes. My understanding it is real easy to over charge the units on the SVX. The other issue I have had was when you first get in the car and start up there is a short period before the fan in the dash turns on. If you notice this doesn't happen the same as before then I suggest you give Jasons suggestions a go.
Tony

[JDW-SVX]

Originally Posted by Dessertrunner

The other issue I have had was when you first get in the car and start up there is a short period before the fan in the dash turns on.

This is normal behaviour. The climate control will start the fan at low speed, and automatically increase the fan speed once the engine coolant has warmed up (in heating mode), or until the evaporator has cooled down (in cooling mode)

Jason.

[dynomatt]

Joann,

don't forget I have the dash switch for you too.

I said to Ziggy that if the compressor didn't work, we could give you the switch instead.

Matt