I have a strange electrical problem that is effecting my aircon system, water level warning light & my wipers. (& its doing my head in!!)

I bought my 02 polo 9n about a month ago. Everything was working as it should do, aircon was fine until the water level warning light started flashing up, the coolant level is above the line, I then replaced the expansion tank to which this did not resolve the light flashing up. I by passed the connector, which seemed to work for a while but went back to the warning light flashing up again.

Whilst this coolant warning light flashes up, the aircon doesn't blow cold air & the intermittent wipers go really fast on all settings.

I booked it in to an auto electrician last week & they said they'd had a similar problem on a polo before & said they could fix it. They said it was a dry joint on some connector either on the steering column or under the dash somewhere.

Its been fine all week, & everything has been working apart from the aircon BUT up until today when the bloody coolant warning light went off again! but now the aircon has started working again, blowing cold air & the wipers still swipe fast on a low setting!!!!!!!!!!!!!!!!!!!

Has anyone else had this issue or similar & fixed it? or does anyone know why these 3 systems are playing up at the same time?

PLEASE HELP

I don't have a wiring diagram for a 9N, so am trying to work out what the problem may be.

The fact that the air con only works when the other problems are present, seems to suggest that there is some high resistance somewhere.

As it seems to be an intermittent fault, finding it will be more difficult, but you need to find the common denominator between all of the faults.

Does the 9N have one of those fuse boxes over the battery? If it does, there are probably some metal fuse links in there (these look more like strips of flat metal, rather than a conventional fuse) These fuse links are prone to cracking, and can in fact continue to work and even test out as having continuity BUT, when they have cracked and you remove them from the fuse box, they fall in two in your hand!! So, IF they are fitted, I would suggest that you remove them and inspect them.

Should one of these be faulty, be sure to buy the correct value as a replacement and DON'T be tempted to make them out of sheet metal - the fuse rating would almost certainly be incorrect.

Regards.

As abive, but also check the positive terminal is clamped securely to the post AND the nut that holds the metal track going into the fuse board is tightened down firmly. I would get a socket or spanner on it and try to turn it if it's hard, then leave it. But if it turns, as it no doubt will, then you would need to use a m6 bolt through one of the other holes next to it as the threads on the stud usually strip on the 6 and 12v engines because of the excessive vibration.

I think I've finally found out why the low level warning light keeps coming on!! I didn't realise that this has 2 functions & when its red & flashing means excessive coolant temperature.

Thing is this was coming on with just the ignition on!!!

I thought i'd start at the instrument panel as everything seems to start at the control module. Whilst I was trying to twist the clocks around to get the plugs at the back, & one of the warning lights come on, on the instrument panel & yet the keys weren't even in the ignition!

After removing the clocks & taking the cover off the back, I checked the soldered joints on the connectors & found that nearly everyone had cracked!!

I resoldered all the joints & so far the light hasn't come back on!

The air con still isn't working so maybe its just a coincidence that this was happening at the same time.

I'll definitely try the positive terminal clamp & check the fuses above the battery. Do you think it might be worth taking off the earth points & cleaning that too?

that is strange. its a good find as nobody else wouldn't' have checked that. could well be a common fail as i have heard of a few of these in the past.

cleaning the earth definably wont hurt, and can only make things better.

Touch wood, so far no warning light or buzzer has gone off yet today.

I got my vcds lite registration through today with ross tech, did an auto scan & it bought this up;

00818 - Sensor for Evaporator Outlet Temperature (G263): Open or Short to Plus

01598 - Drive Battery Voltage: Signal to Low

I did a search for the 00818 - Sensor for Evaporator Outlet Temperature (G263): Open or Short to Plus & it refers to a sensor somewhere buried amongst heater system. Would this cause my air con not to work properly? does anyone have a link for a guide to replace it?

Edited 27 August, 201313 yr by Pwheels

According to elsawin it's a complete dash out to get at that sensor (G 263)

Removing

– Remove dash panel → Rep. gr.70.

– Remove left cross member support.

– Pull connector off evaporator output temperature sender -G263-.

– Pull out evaporator output temperature sender -G263-.

Edited 27 August, 201313 yr by nige8021

Oh bugger!! typical, not sure i want to go down that road of taking the dash out!

so no one's found an easier way to get to this sensor other than to take the whole dash out?

What's elsawin?

Elsawin is what VW use to see how stuff comes apart. Can get a copy online if you know where to look, it's really handy!

I doubt it, you might be able to get to it with the glovebox out, but that's my only thought, maybe from underneath.

Ask Nige to upload the images so you can see where it is, it might give a little insight on how to get to it.. Otherwise, dash out..

Thanks Adam for the info, Yes I know of a few places I might be able to get elsawin lol! It's gotta be better than the Haynes manual anyway!

That would be hady if nige can link me to some pics so I can see what I'm looking at.

Just the air con to sort & that'll everything that didn't work properly, done.

Did you ever solve this? I have the same car and error... I figured it was just the AC needed refilling (had run empty from least owner) but it's still popping up...

After the hot weather we've been having, I want to see if I can get my aircon working by replacing the evaporator sensor (g263) where is the cheapest place to buy one?

Bought mine on eBay, 10 minute job to fit, no need to take out the dash at all, just that footwell vent.

Your aircon should work even with a broken sensor though, just not as effectively... have you had it topped up recently?

its not been topped up since I bought the car about a year ago. It work spot on back then but now it only blows out the same temp as out side. Do they need recharging regularly?

When I plug my vcds in it keeps bring up the same issue 00818 - Sensor for Evaporator Outlet Temperature (G263): Open or Short to Plus which is what I thought was causing it not to work.

I tried pressing a fill valve for a short period & the system seems to be under pressure. Any other thoughts?

Edited 26 July, 201412 yr by Pwheels

its not been topped up since I bought the car about a year ago. It work spot on back then but now it only blows out the same temp as out side. Do they need recharging regularly?

When I plug my vcds in it keeps bring up the same issue 00818 - Sensor for Evaporator Outlet Temperature (G263): Open or Short to Plus which is what I thought was causing it not to work.

I tried pressing a fill valve for a short period & the system seems to be under pressure. Any other thoughts?

I had to have mine topped up 8 months after I had it last done... Not entirely sure why, it should last longer than that. I wasn't able to find any obvious leaks though and it held vacuum well apparently... *shrug*

Definitely replace that sensor though, it's easy peasey to do. 20mins tops. Only a T20 bit required to remove the vent.

Hi,

I have the same issue, I took the passenger glove-box out and couldn't see it as I thought it was on the passenger side... when you say footwell vent which side? and do you have a picture of it? I tried searching on the ElsaWin online manual and didn't find anything for "footwell vent"

It's on the driver side, it's got a single T20 screw to remove. It's towards the left hand side and the pipe has a kind of clip that holds it to the main air vent duct. To remove it, undo the screw, then pulling to the right, wiggle the duct up and down to free the clip. It may require a fair amount of force...

Just had a look today, couldn't see it, I have removed the vent.. and have the picture here http://i.imgur.com/LCEkK2v.png , I believe this is a air sensor?

the T20 Screw was on the air vent correct? I also can't see any pipes, I have tried looking for pictures to help locate it but none helped.

But more annoyingly I have now a air bag warning light appear on my dash.

Just had a look today, couldn't see it, I have removed the vent.. and have the picture here http://i.imgur.com/LCEkK2v.png , I believe this is a air sensor?

the T20 Screw was on the air vent correct? I also can't see any pipes, I have tried looking for pictures to help locate it but none helped.

But more annoyingly I have now a air bag warning light appear on my dash.

That is probably a temp sensor that you can see there. The sensor you're looking for isn't inside that duct, you've only removed it to get access to the sensor above it. It's quite far up, but pops out reasonably easily.

The airbag light is a difficult one, not many people will touch airbag systems, you may have to ask a few garages. Or have a go yourself with vag-com (as I do)

Good luck :)

I will have to have another look I left some of the panels off for ease of access.

I think I know how I tripped the airbag light, when i couldn't see the sensor on the driver side, I thought I'd have another look passenger side as I later found out about this torx on the other vent so I thought i'd take that out as well. However in the process of this I took the glovebox out and this required pulling the connector off the "passenger airbag switch".. (which I have done before but I did turn it to off, this time I left this to on)...

So today I looked with no luck did you have to remove anything else other than the vent? from where I think it is, it looks awkward to access... did you take any of the connectors off the clutch or brake switches (to move the wires out of the way?)

I do have one clear pic of straight up from the vent http://i.imgur.com/XDDSCig.jpg

Also one video where I look around with the camera , http://public-access.mathewkeeton.co.uk/car-stuff/the_g263_mission/VID_20140820_121900.mp4

Oh man, that video brought back some bad memories of being down there... I have however remembered a step... You have to remove the bracket holding the CCU in place (Detailed in your video at 0:45, might be worth removing that switch also from the pedal). I've actually detailed how to do this in another thread and provided pictures of the CCU bracket. I was able to leave the CCU connected, but dangling (it's a really difficult connector to disconnect anyway).

Here is my post on removing the CCU and footwell vent:

http://www.clubpolo.co.uk/forum/index.php?showtopic=204921&p=2596534

Give me a shout if you get stuck again, sorry I forgot that bit!!