Water getting into battery compartment

[beastmodeM5]

Has anyone else experience this? I have noticed every time my car gets a wash or it rains water fills into my battery compartment with the other modules! I already had to replace my battery and 2 of the modules due to water $1600 ! I called BMW North America and told me it could be from the sunroof drain plug and that's normal "maintenance".

[SapphireM5]

I believe you can blow out the drains for the sunroof or take weed wacker trimming line and push it through the drains to clear any blockages. GL water leaks are the worst.

Edit for more info:

If you look in the rear quarter panels I believe the roof drains dump out behind the rear wheels. I think the hose may run right past the battery. Try to find this hose I bet it's clogged. You should be able to see it behind the tire. Good luck

[M5Rick]

How would it get through when sealed shut washing the car; Zanderza a while ago had the same problem of water ingress into the trunk though it was coming through an after market boot spoiler.Water caused a diff control problem with no dsc available which he eventually rectified.

[SapphireM5]

Originally Posted by M5theonlyone

How would it get through when sealed shut washing the car; Zanderza a while ago had the same problem of water ingress into the trunk though it was coming through an after market boot spoiler.Water caused a diff control problem with no dsc available which he eventually rectified.

When the sunroof is closed it still allows water past the seal. That water gets channeled with the roof drains and drain out. Not an issue until they clog or get disconnected somehow.

[M5Rick]

Originally Posted by SapphireM5

When the sunroof is closed it still allows water past the seal. That water gets channeled with the roof drains and drain out. Not an issue until they clog or get disconnected somehow.

It's so tight there closed that I'm surprised any water gets through.

[Herofmine]

Originally Posted by beastmodeM5

Has anyone else experience this? I have noticed every time my car gets a wash or it rains water fills into my battery compartment with the other modules! I already had to replace my battery and 2 of the modules due to water $1600 ! I called BMW North America and told me it could be from the sunroof drain plug and that's normal "maintenance".

Have you ever been on rear end accident?

[Craze]

Open the boot and above taillight there is plastic piece, often clip is broken and water goes down clip hole and tracks along wire harness

Either replace them or silicon them back down

[M5Rick]

Next time I wash the M and after drying will open the roof to see if there are any water trickles present in the channels.

[M5Rick]

Left the beast outside and it's been raining all night.After wiping water away from the sun roof area and on opening it there was no sign whatsoever of water ingress not even a trickle in the channels there.

[TLK]

In past BMWs clogged sunroof drain usually leads to dampness in the back seat floor, bench or B/C pillar. Battery area flood I haven't seen but I've not dealt with this on F10. Usually water in trunk is from lid or taillight cluster seals going bad