2002 Passat comfort control unit?

celica1994

Hey hows it going, the last while my Passats alarm has randomly being going off at night, and now even more recent randomly the interior light will come on inside the car for no reason, I inspected the passengers footwell and it seems rather damp undernet when I lifed the rubber matt off the floor. ive heard this can be a problem with moisture getting into the comfort control unit, How would I fix this problem, any suggestions is welcomed!

randy hickey

Have you had your upholstery valeted recently?

If not, the prime suspect in the cases is the pollen filter below the glovebox. Probably €15 to €20 and you can do it yourself.

MugMugs

Could be a bit late to be honest and could require a new unit.

There's wee drain holes under the bonnet around the battery area from memory that backs up with gunk. This causes water to back up into the pollen filter and back into the car. Solve this issue first and vax the carpet. The unit if completely goosed can be a pricey fix from memory.

celica1994

cheers for the replays. so ill try changing the pollen filter, should I lift the carpet and check out if theres any more water under it?

randy hickey

Had this on a relatives W202 last week. Replaced the pollen filter,no change after a few days.Started to panic thinking it was the drain tube from the a/c evaporator.

Turns out we were overthinking it-as above, it turned out the windscreen drains were blocked with moss.Guess what was directly beneath the tray full of water on the passenger side?Yep, the air intake to the cabin heater- so this water was overflowing down around the blower motor, heater matrix etc, and down into the passenger footwell.
Took approx half an hour to unblock and cost nothing.She's dried out now, but there appear to be some electrical issues showing up today- so I must check if the cabin control unit is in the same position as yours OP.

celica1994

just looking at videos of pollen filters there, is there suppose to be anything covering the pollen filter while its sitting there? I looked at mine the other day and you can lift it out without having to remove anything?

Educate

From unfortunate personal experience there are a number of potential causes of water getting into the footwells of the B5/5.5 passats - check this out for a breakdown.

By what you've described it sounds like the pollen filter seal that requires you removing the pollen filter housing (DIY of this here - scroll to post #9) and replacing the crappy original seal at the bottom of it with a new one (~€25 from VW for seal + ~€25 for the foam seal). Mine was resealed with silicon instead of the replacement seal and it's worked very nicely (famous last words).

If you're DIY inclined you would want to get the CCM out from under the carpet and dried out pretty rapid if it isn't too late already (you can pull it out a certain distance while still wired up to get it out of any puddle of water it could be currently sitting in and then dried as best you can). This means lifting the carpets, which can be done by first removing the plastic covering just to the left of where the passengers left foot would be (if memory serves me - it's a single screw, then about 4 inches above this is a clasp that pops out, then you have to sort of pull the part as if you are twisting it clockwise around the axis of the screw just to release it from another catch) and then getting your fingers under the plastic trim running down the length of the car to pop it up to release the carpet so you can then get a look under it (to entirely remove the carpet requires seats and center console being removed - I didn't do this and just got towels and whatnot under the carpets to get the water out).

If you need to lift the trim all the way to the back seats this may require lifting out the rear seats as there is a screw holding it in place that is underneath these seats - I didn't have to remove the seats as I lifted the trim enough to pull out the carpet out from under the trim so you should be able to do this also.

From my experience I'd suggest that you don't go near the side plastic trim unless it's a warm enough day (pretty unlikely at the moment of course) or you've had the aircon on hot for a long time to warm up the plastics inside the car (probably difficult for you since it would seem the CCM is already wet) - the plastics snap very easily when cold...or maybe I was just too rough but did notice they were much more pliable when I'd left the aircon for a long time attempting to dry out the car and nothing snapped until I went at them on a cold morning.

Sames goes for the windshield cowl which you'll have to remove to get the battery out to check the drain holes beneath it which is something I'd suggest you do regardless - I'd suggest this because I had blocked drains, a perished pollen filter seal and a damaged bonnet release cable seal which all together let a lot of water into the car on both sides. Put a towel around the pollen filter as best you can, close the bonnet and pour hot water over the cowl to help it bend rather than snap (replacement was €26 from VW) - removing the cowl will also require first removing the wipers which can be a serious pain to remove if they've never been off before and also removing two clips that keep it in place.

Plenty about the various issues in the linked threads above so hope you get it sorted - best of luck.

Educate

celica1994 wrote: »

just looking at videos of pollen filters there, is there suppose to be anything covering the pollen filter while its sitting there? I looked at mine the other day and you can lift it out without having to remove anything?

I think on some B5 models there was no plastic cover over the pollen filter / battery area (the thing the yellow arrow points to but I could be wrong as I have a memory of reading this somewhere) but to my knowledge a 2002 passat would be a B5.5 anyway. There may also be a small plastic covering that catches water that might leak between the windshield cowl and the engine bay battery cover "thing" (plastic covering the yellow arrow points to above) but other than that there is no plastic covering on the pollen filter itself (at least there wasn't on mine).