Disconnected Cable by Battery

I swapped out the battery on my 05 325xi last night only to find that 1) the previous owner didn't connect the vent on the old battery (yikes) and that 2) there seems to be a cable of some kind that was hanging loose behind the battery and I have no idea what it belongs to.

Any thoughts?

Originally Posted by dvation

I swapped out the battery on my 05 325xi last night only to find that 1) the previous owner didn't connect the vent on the old battery (yikes) and that 2) there seems to be a cable of some kind that was hanging loose behind the battery and I have no idea what it belongs to.

Any thoughts?

I am almost certain that it connects to the tilt sensor for cars that have the factory alarm.

My vehicle doesn't have the factory alarm, does that help to confirm or deny your suspicion?

Originally Posted by dvation

My vehicle doesn't have the factory alarm, does that help to confirm or deny your suspicion?

It doesn`t "confirm or deny" anything, but don`t lose any sleep over it....BMWs are pre-wired for lots of things that may or may not currently be in your vehicle.

The owner has what looks like the same replacement battery I wrote about for my battery replacement DIY:
- Pictorial discussion of charging, testing, removing, & replacing the bimmer battery



EDIT: Presumably you re-connected the vent.

Here's what reputedly can happen if you don't:

Originally Posted by Fast Bob

It doesn`t "confirm or deny" anything, but don`t lose any sleep over it....BMWs are pre-wired for lots of things that may or may not currently be in your vehicle.

Great, thanks. Nothing appears to be out of order so I'll just tuck it back in.

Originally Posted by bluebee

The owner has what looks like the same replacement battery I wrote about for my battery replacement DIY:

EDIT: Presumably you re-connected the vent.

I did reconnect the vent but didn't take notice on whether I crushed the hose when clamping down the battery - I'll check that now. Thanks for the tip!

Originally Posted by dvation

I did reconnect the vent but didn't take notice on whether I crushed the hose when clamping down the battery - I'll check that now. Thanks for the tip!

Wow. I'm heartened. Someone actually read the link referenced!

Thanks!

Here's a picture from another DIY showing the hose most clearly for that battery in a bimmer.
The danger is the hose can EASILY become crimped by the heavy battery against the fenderwall.

Originally Posted by SJBimmer

I am almost certain that it connects to the tilt sensor for cars that have the factory alarm.

The tilt sensor actually uses a six-pin connector. That's most likely one of the two "mystery connectors" DIYers tend to find. This one was supposedly used to disconnect the battery during shipping. The other is located below the rear seat cushion and was used to monitor the battery condition while the car was shipped from the factory.

Originally Posted by G. P. Burdell

The tilt sensor actually uses a six-pin connector. That's most one of the two "mystery connectors" DIYers tend to find. This one was supposedly used to disconnect the battery during shipping. The other is located below the rear seat cushion and was used to monitor the battery condition while the car was shipped from the factory.

Good to know! Thanks for the info! I tend to believe that alarms are almost useless anyway, so I never installed one in my car.

Originally Posted by G. P. Burdell

two "mystery connectors" DIYers tend to find.

Now THAT is interesting!

We have a "mystery connector" in the E39 (inside the driver's side front door) that I've been trying to track down - which might have something to do with the factory.

How DID you find this information out about the 'factory mystery connectors' (which is a new topic to me)?

Is there a list of them somewhere?

Originally Posted by bluebee

How DID you find this information out about the 'factory mystery connectors' (which is a new topic to me)?

Is there a list of them somewhere?

There's no list, but forum members are constantly starting new threads about them. Folks usually find (and post about) the connectors when they change the battery, replace the fuel level senders, or install aftermarket stereo equipment.