water in battery compartment 3 series E92

[moboga]

I had a problem with my 3 series E92 coupe a week ago. The car would not start one morning and I called BMW assist. The chap that came out to me was able to start the car with his own battery but when he opened up the battery compartment in my boot there was 3 inches of water in the battery housing area.

Car was then towed to dealer. The dealer said the battery and cabling was all corroded etc and has to be replaced. They have not identified where or how this water got in.

I would like to know if there are any cases similar to mine how the water might have got in. The dealer are telling me that it is v unlikely to be covered by my warranty ( extended) as the damage is due to water. Does this sound right? They said they MIGHT be able to do a goodwill request with BMW but this is still up in the air. They have qouted me nearly £1900 to fix this problem.

All comments and feeback much appreciated!

[moboga]

Not had any shunts/ damage. It is very odd how this water has got in. No external/ internal damage, no water damage elsewhere in the boot!