Major Condensation & Interior Ice Issues

[grantwils]

Hi Folks

I've got a 2001 IS200 which is really begining to annoy me. The interior glass is covered in condensation really badly when it's left overnight. With the cold weather it has been turning to ice so I've had to scrape the inside of my screen. Today I left the car parked up at work and when I got in tonight the outside of the glass was fine but the inside was frozen!

At first I thought I must have a leak but there are no damp carpets anywhere - I can't find any damp patches in the cabin or the boot. Does anyone have any idea what it could be? It's driving me nuts!

[sparkystav]

Use the aircon, itll dry the air out creating less moisture in the car

[grantwils]

Use the aircon, itll dry the air out creating less moisture in the car

Thanks for the reply however I do use the aircon. I don't think I've got across how bad the condensation is - it's not something like recirculating the air or not using the air con.

[The-Acre]

Hi Folks

I've got a 2001 IS200 which is really begining to annoy me. The interior glass is covered in condensation really badly when it's left overnight. With the cold weather it has been turning to ice so I've had to scrape the inside of my screen. Today I left the car parked up at work and when I got in tonight the outside of the glass was fine but the inside was frozen!

At first I thought I must have a leak but there are no damp carpets anywhere - I can't find any damp patches in the cabin or the boot. Does anyone have any idea what it could be? It's driving me nuts

I have to say, whenever I've had condesation problems to that extent it's always been from a leak, and it doesn't have to be a major leak. I don't know if the IS has a sunroof as standard but with my LS water was coming in from the sunroof because the drainage holes were blocked, a common problem it seems, it caused really bad condesation. Worth checking maybe. Does it get worse when it's been raining?

[kev dood]

Check the rear wells in the boot. The sunroof drains run into there I think and there is a little drain hole/pipe that can get bunged with dirt. It does sound like there is a minor leak somewhere to get that much condensation.

You ever had a windscreen replaced?

[Mr.Rudus]

has the car been damage reapaired at any point?

there is a leak from somewhere that is causing this.

you could have a minor crack on the matrix unit under the dash.

[lexynik]

could be leaking from the windscreen like KEVS

[grantwils]

Thanks for the above feedback guys - it's certainly given me some likely candidates.

It's the original screen - I'll double check for cracks.

It's never been accident repaired other than a smart repair for a scuff on the bumper.

I'll check the rear wheel wells in the boot for any moisture to see if it's the sunroof.

I also noticed that the headlights were acting a bit strange recently when I parked up - the link to KEVS post mentions water leaking into the headlight relay so this is a definate suspect. This also seems to confirm that I didn't imagine the lights flickering on and off so I'm not going insane which is good!

[lexynik]

bit more info here from a past thread HERE

[MorrIS200]

try taking your floor mats out if they are wet. mine where soaking and caused this problem, took them out the next night and no problem.

[grantwils]

Thank you again to lexynik - should that be disconik now? I've had a look over the 2nd link and definately think I need to look into the fusebox with a torch and sort it.

Some symptoms I've noticed...

Interior condensation so bad that I have to use an ice scraper on interior windows.

Lights flickering just after I turn them to off (normally leave them at auto so it's not a problem)

Remote locking/unlocking not working occasionally (really annoys the neighbours when I set the alarm off as I leave for work)

To be honest I've had the sunroof blind shut the last few days and not had any issues. Think there will be a bit of trial and error with this over the next few days to find the cause and fix the problem. Will report back with how I get on. Any more advice would be great. This thread has given me a few useful things to check - gotta love internet forums!

[kev dood]

The main issue with the headlights is that the front ones (not rear also) will come on and you can't turn them off. Only way is to take out the relay under the bonnet. I think from memory its the blue one - standing facing front of car is under the plastic cover on the left rear - near Battery.

Culprit is water running down the cable harness behind the drivers side kick penal which comes off fairly easily. Plastic nut at back end near accelerator pedal. The unclip the bottom door seal trip and it will pull out towards the back of the car.

There is (I think) a grey connector towards the back of the main relay control board which is the culprit. If its not grey then its blue!!

Pull it out and check connector pins etc for water. Also see if you can look into connector it plugs into. If there is, dry it out with kitchen towel and a hairdryer. If you are lucky, then this will cure it and once windscreen sorted you will be fine. If not, then relay is not cheap (if its knackered - which is probably rare) or worse, the main control board is knackered which is £500+!!

Other common water faults from leaky screen is the alarm/locking ECU acting odd and either being very slow at locking, or not disabling the alarm when it does unlock. Even when put key in and start the car it will go off until times out (fairly quick).

All the dash gauges can also start playing up and not working, or lights flashing at you when shouldn't. An E can appear where the outside temp gauge is.

On mine, I had all of that, but couldn't work out where the water was coming in from for the alarm/dash issues. But, after disconnecting the batteryh overnight which will reset the ECUs it was all fine. Fingers crossed there has been no permenant damage - I dont think so.

The other area worth checking is that there are no damp leaves under the back of the bonnet where the air vent intakes are. That can often be a cause in other cars.