BlueHorse

Need to replace battery on 2004 525i. Battery was factory OEM build Jan 2004.

But I can't find a way to disconnect the positive terminal, which is burried under a few plastic/metal pieces, as you can see in the picture below I copied from another memeber. The yellow circle is where I think I need access in order to disconnect the positive terminal from the cables. I can open the plastic cover in the green circle, and underneath it there is a nut securing the vertical red cable above.

How do I disconnect the positive terminal though? Do I have to unscrew the bolt in green circle first? And then what?

Thanks.

Scott2007

There is a little red flap that you lift, then you can use 8mm? socket to loosen the clamp. (going from memory). Be darn careful with shorts - you hit ground - you likely will do damage.

Scott

healthservices

Remove the ground first so you do not have to worry about touching the positive to a ground source.

luigi524td

+1

The red plastic cover over the positive battery terminal can be deceiving. Only the small red cover/tab (it's about 1/2" square) at the very edge of the battery cable cover needs to be lifted to get access to the bolt that will allow removal of the battery cable.


It is VERY IMPORTANT to disconnect the NEGATIVE cable FIRST!!!

BlueHorse

Still confused. I can only see one nut (in the green cirle of my photo). But that nut seems to be away from where the positive terminal is located (the latter should be 1 inch further out toward the edge of the battery, if it is symetric to where the negative terminal is located). Is the nut in the green cirle the one and only one I need to unscrew?

Thanks.

healthservices

And yes when removing a battery always remove all negative battery connections first.

When reinstalling always put the negative connections last.

pauliehcfr

remove the smaller nut on that terminal. be sure to disconnect the negative 1st or you'll get quite a spark show!

jaycal3

Your confusion scares me... let a friend help or let the dealer do it so they can register the new battery...

BlueHorse

Don't be scared. Only thing I am not sure here is how to access that "smaller nut" in the photo, i.e. the one to the left. Mine is covered by red plastic flap that I didn't seem to be able to open earlier today. Will try tomorrow.

I have gone through more than 10 threads here regarding registering battery, and talked to dealer, independent mechanics and Sears. I have decided to go without battery registration. The money saved will be enough to pay for another new battery.

Thanks.