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Odyzeus

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Discussion starter · #1 ·
Since my Ody sometimes sits for several weeks (or longer) I am thinking about adding a Battery Disconnect switch to keep the battery from draining during those times.

Anything I should be aware of? Security codes? Audio system?

Thinking of just getting a very simple master switch like they use for campers rather than one of those remote controlled ones. Just to keep it simple.

Thoughts?
 
Discussion starter · #3 ·
K...
Not to overthink this, but say I disconnect the battery and close the hood... How do I ever get in again with the locks now disabled? Does the little manual key override this, or is that still requiring battery power?
 
Disconnecting the battery will reset your audio setting and driver memory functions if your model has that. It can also reset adaptive settings like transmission shift points and fuel trims.
If you are parking it close to an outlet for storage you would be better off with a smart battery maintainer like a BatteryTender or Noco Genius than unhooking the battery.
 
@Odyzeus
The pull out key from the key FOB will unlock only the drivers door. And yes you will be able to open the engine hood.

On the kill switch, yes you will lose some settings, but nothing to be concerned about. Do not install a knife style switch. If the blade does not match the side contact portions well, it will heat up and corrode or not have enough contact area to start your ODY. I do not see a good remote high current kill switch most of them are under 240 AMPS. Your starter can draw that if engine is cold and oil has separated from bearings on start up. I like the idea of a remote one, but they say to keep under a 4 Liter engine only. They would probably would be using a scr to turn it off and on by. Good luck on your choice... let us know what you will use and after a year of use to see how it does.
 
Discussion starter · #6 ·
@Odyzeus
I had looked at Amazon as well before answering your question. This one would require you to take your battery post clamp off your negative battery cable and crimp on a copper lug. and build another cable with another copper lug and a new battery post clamp.

If you was to try one that had the 2 separate built on battery post and clamp like this:
Ampper Top Post Battery Disconnect Switch, 12-48 V Battery Power Cut Master Switch Disconnect Isolator for Car, Vehicle, RV and Boat (Negative, On/Off)

Image

if it failed you could put the negative battery cable back onto your battery right then. Assuming there is enough room in the engine compartment for this to work.
 
So the key lock cylinder is no longer physically linked to the lock? :unsure: Then if the battery dies or is disconnected there's no longer a way to unlock the door!o_O
 
Discussion starter · #10 ·
@Odyzeus
I had looked at Amazon as well before answering your question. This one would require you to take your battery post clamp off your negative battery cable and crimp on a copper lug. and build another cable with another copper lug and a new battery post clamp.

If you was to try one that had the 2 separate built on battery post and clamp like this:
Ampper Top Post Battery Disconnect Switch, 12-48 V Battery Power Cut Master Switch Disconnect Isolator for Car, Vehicle, RV and Boat (Negative, On/Off)

View attachment 186734
if it failed you could put the negative battery cable back onto your battery right then. Assuming there is enough room in the engine compartment for this to work.
Thanks again DJ, very good point! Although I have an Elite version and the battery cable goes to some sort of clamp/bracket/distributor plus the whole thing is covered with a plastic cover which makes this undertaking difficult whatever form factor the switch has.

Is there perhaps a "Master Fuse" one could pull to cut off the battery from everything else?
 
Discussion starter · #11 ·
So the key lock cylinder is no longer physically linked to the lock? :unsure: Then if the battery dies or is disconnected there's no longer a way to unlock the door!o_O
🤪
Thank you for pointing out my mental limitations.
Good to know I will still be able to get in without a coat hanger even with the battery disconnected.
 
Looking at the PDI inspection sheet you could also try and remove the #18 "Back up" fuse from the fuse panel.
"To lower battery drain during shipping, the No. 18 BACK UP (10A) fuse is removed from the under-hood fuse/relay box and stored in the glovebox. Make sure to turn the ignition OFF and wait at least 1 minute before installing the fuse."

BTW: This summer we were gone for 3.5 weeks and our 21' Touring with the factory installed battery started immediately when we got home.
 
Discussion starter · #14 ·
Looking at the PDI inspection sheet you could also try and remove the #18 "Back up" fuse from the fuse panel.
"To lower battery drain during shipping, the No. 18 BACK UP (10A) fuse is removed from the under-hood fuse/relay box and stored in the glovebox. Make sure to turn the ignition OFF and wait at least 1 minute before installing the fuse."

BTW: This summer we were gone for 3.5 weeks and our 21' Touring with the factory installed battery started immediately when we got home.
Thank you, it's a thought, but I doubt a single 10A fuse will help much to separate the battery. It is probably something like the entertainment system which may still draw small currents while the vehicle is off.

The weird thing is that it's not just vampire draws that drag down the battery SOC. For some reason, and I assume it's an issue with my specific vehicles computer or charging setup, when I start to drive it charges the battery with ~14V, but after a while, maybe an hour or so, drops it down to 12V. It then goes up and down a bit, but it seems like the maintenance/float charge (after the battery is sensed as full) is incorrect.

And so what happens is that when arriving after a long drive, the battery is often at around 12.3V which is not good, and then over a few days discharges more (than I am comfy with).

I am going to check for parasitic draws though. I don't feel comfortable letting the car stand for 3 weeks without recharging it. Don't want to damage the newly installed AGM battery by going below 12V. I do have a solar panel on top and top off the battery via a charge controller as needed. It's just stupid that I arrive with a near empty battery after a long drive.
 
The weird thing is that it's not just vampire draws that drag down the battery SOC. For some reason, and I assume it's an issue with my specific vehicles computer or charging setup, when I start to drive it charges the battery with ~14V, but after a while, maybe an hour or so, drops it down to 12V. It then goes up and down a bit, but it seems like the maintenance/float charge (after the battery is sensed as full) is incorrect.
So it's dropping down to 12 volts even or is it like 12.6, 12.8, something like that? Because that sounds more normal.
 
Discussion starter · #17 ·
So it's dropping down to 12 volts even or is it like 12.6, 12.8, something like that? Because that sounds more normal.
Yep, drops down all the way to 11.8V, climbs to 12.2, then jumps up to 13.8 then back down, really Oddy to watch.

A faulty charge sensor sounds likely. Going to see what changing this involves.
 
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