water collecting in battery compartment

**Topcat65** · 01-06-2008,10:02 PM

I have just noticed a lot of water in the battery compartment, and I am concerned this will rot steel or leak into the cabin. Should there be a drain hole and if so, where is it?

**a8 tech** · 01-06-2008,10:16 PM

https://www.vwaudiforum.co.uk/forum/s...er+leak&page=2 unblock the grommet and clean out the drain channels

**Crasher** · 01-06-2008,11:06 PM

A huge problem on the Passat, Superb, A4 and A6. If it gets high enough it will spill over into the heater inlet, flood the floor on the passenger’s side and cause problems with the central locking system. If the servo sits in water (as it does when this happens) it will slowly draw water in and this will cause the brakes to jam on, starting with the left front. Cleaning the drain tubes out (one under the battery tray and one under the servo) takes about half an hour.

**98passat** · 01-06-2008,11:58 PM

I had the same problem, you need to remove battery & battery tray. There are two drain holes, one under battery the other underneath brake servo. Both can block with debris, leaves etc.

**exaisle** · 02-06-2008,09:46 AM

Tell tale signs are dampness in the passenger footwell....OR more condensation than normaal on the windscreen. It's one of those things that if checked during services can save £££ later on..

**tone70** · 02-06-2008,10:23 PM

Warning, i had exactly this problem on my 1.8t 2000 w Passat saloon shortly after getting it and took the battery out to unplug one of the holes and when connected it back up the car went in to limp mode, the VAG technician from the dealer i bought it from said that with 2000 models some cars do this, which is a pain so if i need a new battery i have to go to VW and then get them to reset the engine!! This is not in owners manual as i checked what things needed to be reset. Good luck hope yours isn't one that limps!

**Crasher** · 02-06-2008,11:03 PM

Only the petrol models get upset by disconnecting the battery due to the adaptation of the throttle body being lost and it will be worse if the throttle body is very dirty.

**MalcQV** · 03-06-2008,07:49 AM

Originally Posted by Crasher

Only the petrol models get upset by disconnecting the battery due to the adaptation of the throttle body being lost and it will be worse if the throttle body is very dirty.

Last time I had the problem I did dis-connect the battery to remove it. It was off for about 1/2 hour but never had any problems afterwards. Is it just hit and miss or is there a time limit on the battery being disconnected?