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Help !!!!!

Does anyone have any ideas why my air con keeps starting up in Economy mode when I switch the ignition on and won't come out of Econ until I've switched the ignition off and on a few times then it comes on and works ok.

Any suggestions much appreciated.

Is your battery OK? If the voltage drops below 9.5, your AC wont work properly.
Quote from ElsaWin: "If the vehicle's electrical system voltage (at connector -B-, contact -3-) drops to a value below 9.5 V, the compressor will be switched off for at least 25 s. It is switched back on only when the voltage has exceeded a value of 10.8 V."

I would check if the AC fan is starting when you switch the ECON off. If your vehicle is 2002 onwards, there is N25 magnetic clutch on the AC compressor, that may be playing up as well.
The best way would be to connect the vehicle to Vagcom and see if there is any fault recorded.

It now seems like the fans are running even when in Econ mode. ?

You could have a faulty temperature sender which could confuse the air con and make it switch off.

Bring up the coolant temp on the air con display to see. See FAQ.

Thanks I'll give it a try. Think I'm gonna invest in the obligatory vag-com.

Expensive but worth it. I have used mine to diagnose problems on 4 or 5 different cars since I got it at the end of last year. Once you get past the paranoia of using the program, it is a really useful tool.

So I've checked the coolant temp and it came up 65 which looks the same as coolant temp gauge, I noticed the outside temp on the DIS is showing 18 and I'm sure it's not much more than 13 or 14?

Ignore the outside temp. It's pure fantasy.

When it was reading 65 were you able to turn the air con on?

Vagcom will pay for itself quickly.

Shoppinit wrote:Ignore the outside temp. It's pure fantasy.

When it was reading 65 were you able to turn the air con on?

Vagcom will pay for itself quickly.

NO air con wouldn't turn on, fans still run when the engine is running.

Just about to order vagcom

Mine had a similar problem a while back which turned out to be a sensor/switch that was shorting out. Always effected me when it was raining, when the sun was out it would be fine.

Maximo wrote:Mine had a similar problem a while back which turned out to be a sensor/switch that was shorting out. Always effected me when it was raining, when the sun was out it would be fine.

Will have to investigate this as oddly enough we had a bit of rain down here at the weekend.

Do you recall which switch it was?

Do you recall which switch it was?

Sorry no, but it was near the condensor as MRC took off the front bumper to get at it. I think it was some kind of preasure sensor switch. I'm sure Shop will be able to tell us.

Right, plugged into Vagcom and came up with

00819 - High Pressure Sensor (G65)
29-00 - Short to Ground
01592 - Air Quality Sensor (G238)
57-00 - Electric Circuit Failure

So probably going to go for pressure switch to start with ??

The air quality sensor has nothing to do with your problem.

The other switch is the source of your problem. Phew.

Shoppinit wrote:The air quality sensor has nothing to do with your problem.

The other switch is the source of your problem. Phew.

That's what i thought, and i can get the sensor out without taking the bumper of which is a result.