The battery DIY, without losing settings

[gregs210]

Originally Posted by keyhole

Hope this isn't a dumb question, gregs - but why can't I just turn the ignition switch to pos 1 ?

Hey, Keyhole. I just saw this; my apologies for not answering sooner. I don't know if it's in the WIS or what, but my default understanding is that if the battery is being disconnected, the key should be not only off but in your pocket. Just having it in the ignition energizes some circuits and with it in POS 1 lots of stuff is hot, that would likely overload a 9V battery plugged into the cigarette lighter, with all sorts of potentially ugly results ... the least of which is that it would drain flat and you'd end up resetting everything.

My default position when I post tips and DIYs on here is to post things that (1) work and (2) are generally safe (both from a personal as well as a car standpoint) if done as suggested. They may not necessarily be the easiest or shortest or fastest or (fill-in-the-blank), but they fit that general framework. If you want to go test the key-on-cigarette-lighter-device-plugged-in and post your results, let us know. Myself, I'm not excited about the possible downside.

Originally Posted by texholdem

it may sound trivial but I suppose it would also work for saving the settings if using an AC-DC converter with 12V output instead of the 9V-Monoblock too, right?

Hi, Tex. With a couple of caveats, I don't know any reason that shouldn't work. I know I wouldn't try an automatic battery charger, for example, as those look for load, resistance, etc. and vary output; I don't even want to guess what those might do when the battery was disconnected. Also, when the battery is disconnected there is an "open" loop in the circuitry; a 9V battery isn't enough to do any damage to anything (even if you let the positive cable hit the frame), depending on the current available a 12V output conceivably might. Again, I can't think of any specific reason it shouldn't work ... but refer to my default position above.

Gents, thanks for the thoughts and, as always,
Take care and enjoy the ride.
Greg

[SamirD]

Hate to bump an old thread, as I'm probably missing something simple.

How do you use the latch? I've tried pushing on it and pulling on it. Looking at it, it even seems like it could slide to the side. I don't want to break anything, so any assistance is welcome.

I really want to get this e55 back on the road. It's been sitting in a nice climate controlled garage for two years now, but it deserves to see the road.

[Matt L]

By "latch" do you mean the latch that holds the rear seat onto the car?

If so, reach in, find the lever, and pull straight up.

[SamirD]

Thank you, that's exactly the latch I was posting about. I should have been more clear.

I will try pulling straight up towards the roof.

[SamirD]

Thank you! That did the trick. I'm usually so much more mechanically inclined. Battery is out and ready for replacement.

[Matt L]

Don't feel bad. I had to look at the owner's manual the first time because I couldn't figure it out either.

[SamirD]

And if anyone is interested, the torque required to take off the battery hold down clamp is 20ft/lbs. I plan to tighten it back to the same spec.

[SamirD]

Originally Posted by Matt L

Don't feel bad. I had to look at the owner's manual the first time because I couldn't figure it out either.

It was in the owner's manual?!? Now I feel like a real idiot. Yep, right there on page 297.

[dave e320]

:QUOTE=gregs210;2328708]It's been a while coming, but here is the post for how to change your battery yourself. With pictures, of course.

This includes a setup that will help you avoid having to reset everything, which was probably the more enjoyable part of this exercise for me. If you don't want to make it yourself, I'll sell you one for $15 including the 9V battery (a new alkaline, not the one from my smoke detector!).

Take care and -- as always -- enjoy the ride,
Greg[/quote]

brilliant . thanks for the time to post this piece of info most helpful..:

[jlbarnes]

Why not just use jumper cables from another car to hold the voltage while changing the battery? Of course, no key in the ignition switch while doing this. I have not tryed this but may someday when needed if there is not a known problem.