air con help

[pwheels]

Hello all I've just joined the site so my apologies if this in the wrong place. I bought a 02 9n 1.9tdi sport on Thursday & im have an intermittent fault with the air con.
It all started on Saturday when i went for a drive & the aircon had been working fine the day before. while driving the low water level light came on with 3 bleeps from a buzzer & the aircon was blowing outside temperature.
I googled the problem & it suggested checking the expansion tank level sensor so I unplugged the connector & plugged it back in & the water level was just above the full line.
Going through the history on the polo, it had a new expansion tank + sensor last year & the aircon was recharged last week.
The light has now gone off so I assume it was a dodgy connection. The aircon was working fine this morning blowing nice cold air but driving home from work, it has gone back to blowing warm air from outside!!


If someone could help me out, it would be much appreciated or at least tell me where to start looking for faults.

cheers, paul

[pwheels]

Just fitted a new expansion tank & im still getting a red flashing low water level warning light!!

Is there anything else that triggers this light?? Its driving me NUTS!!!!!!!!!!

[alexperkins]

The sensor can fail often on these. It could be that. Try shorting the sensor wires together and see if the fault clears.

[pwheels]

I will give it a try! Can't understand why it's still doing it after fitting a new expansion tank! If this doesn't work an expensive trip to VW I think.

[alexperkins]

To add, the water level and the air con are likely unrelated and the fact your air con is misbehaving could well be coincidence

The air con uses refrigerant on a different circuit - the water beeping is relating to the engine cooling.

[pwheels]

oh ok, it was only that I read some where that if the expansion tank level is low & the warning light comes on, it shuts the aircon off via the ecu? or something like that.

The strange thing is I made up a bypass (2 connectors & a bit of wire) this morning & put it in the plug for the expansion tank sensor connector. I took the car out on a long drive & its been working fine with no bleeps or warning light. Plus the aircon is blowing cold air again. I think im gonna leave it like this & just keep an eye on the water level every so often

Thanks for the tips & advice, its always a bit daunting when you buy a new car & something starts playing up.

[alexperkins]

I would look to replace the sensor in any case, as its quite possibly faulty if bridging the wires works ok

[pwheels]

I left the bypass wire connected to the expansion tank connector for a couple of days but the light has come back on now!
I've got my polo booked into a garage this morning, maybe they can figure out what's wrong with it.

[wildman_33]

I get the coolant level light come on after every service due to the coolant being replaced and filled up to half way between the two marks, I just get it topped up to the max marker and it goes away until my next service.

[pwheels]

I topped it up to just above the full line but it still comes on but it's too inconsistent to be a fault with the level sensor. I took my car to a local garage where I bought the car but low & behold no light came on & the air con was working lol!
But as soon as I got in it, the light came on, so maybe my car doesn't like me!
It's booked in with an auto electrician next Friday who say they've had a polo in before with a similar issue.
Fingers crossed they can sort it & I'll post what the problem was for future use!

[pwheels]

update after the auto electricians had a look, they said it was a dry joint on a connector under the dash somewhere & the warning light has stayed off ever since but the aircon hasn't worked either
Now for the strange bit, a couple of days ago the warning light came on yet again but this time the aircon started working!!! The next day the warning light didn't come on & guess what, the aircon doesn't work again!!!

This is starting to sound more like a broken connection or bad earth & not so much of a bad coincidence!

I've been reading lots of posts from different forums where people have had the same issue, replaced nearly everything from the expansion tank to both temp sensor & still not solved this problem.

So if im understanding this right, the light on the dash which looks like a thermometer with water at the bottom, flashes yellow or orange for low water level & red for excessive engine temperature??
if so my car runs fine, no over heating, the temp gauge gets up to temp 90 degrees with no problems & no over heating. From this the warning light on the dash must run to the engine temp sensor & the low level warning light, via the ECU?
Could it be possible that this is stopping my aircon from working properly?

Im not very good with tracing problems to do with electronics & wiring so if some could let me know that this is possible then that would be great & I can start trying to solve this problem once & for all!!!!

[pwheels]

I now have a vcds-lite registered from ross-tech & these 2 errors came up;


00818 - Sensor for Evaporator Outlet Temperature (G263): Open or Short to Plus
01598 - Drive Battery Voltage: Signal to Low


does anyone have a guide or a link to replace the Sensor for Evaporator Outlet Temperature? or can tell me where I can find it?

Im guessing the battery error is just a case of replacing the battery?

[RUM4MO]

I think that there are guides to replacing the evaporator sensor, that could be the one that is stopping your chiller working I'd guess. Now where to find this guide, not in here I would imagine, you will need to hop over to forums where people actually work on their cars a lot, ie www.briskoda.net and www.seatcupra.net Fabia and Ibiza 6L are similar to these cars.

[pwheels]

so I finally got to the bottom as to why my stupid light kept coming on, on the dash. The coolant level sensor shows up as orange or amber but when its red & flashing & the buzzer goes off means "excessive coolant temperature" which was quite amazing seeing as it went off after only just starting the engine.

I looked through lots of electrical diagrams as to where these 2 warning lights run to & they both go to the control module in the instrument panel.
Whether or not that is correct but whilst removing the instrument panel & trying to remove the 2 connectors at the back, one of the warning lights came on, which made me think its a loose connection somewhere.

after close inspection on the circuit board at the back of the instrument panel where these 2 connectors are I noticed nearly every soldered joint had cracked!!


Its now been a couple of weeks since I resoldered all these including the ones the other end of the board & the light hasn't been on since......

My aircon still isn't working, so when I get five minutes & can replace the Evaporator Outlet sensor without taking the whole dash out then hopefully that'll be all everything working as it should & I can start looking at some engine mods!
if anyone else is having similar issues, it might be worth looking at these soldered joints!!

[RUM4MO]

Good for you! Dealer would want a few hundred pounds for buying in a new pod and then some more for programming it, and some more for fitting it!!

The multi-gauge pods on the Ibiza seem to be the worst offenders, I'd guess that the cable harnesses are too short or tight and end up pulling that connector's pins out of the PCB.

Oh, remember these cars are built in Spain using parts manufactured here there and everywhere!

No sign of that fault yet with my wife's 2003MY 1.4SE, one other cheeky fault can be the brake pedal switch, that one brings quite a lot of lights on, as can a faulty brake light bulb. I'd reckon quite a few people have put their car in only to get hit for £50+ for diagnosis, and £0.59 for the faulty bulb OUCH!!