Major Contributor
I fitted a second battery under my rear seat (my main battery is next to the engine). I took a feed from the unloader relay (blue wire I think) to a lovely illuminated switch on the sunroof panel, which switches a 30A fused relay under the rear seat. This relay connects the 2nd battery to the main live cable as shown is Shogun's diagram above. The great thing about doing it like this is the 2nd battery can only be charged when the engine is running and the overhead switch is illuminated. Pure genius!
4 Grand Master
Mini-fridge? One of those electronic jobs without moving parts?
I have one, it SUCKS power. If you want this thing to run 24/7 be prepared to install a fork lift battery.
I bought one for a road trip thinking it would be nice to have a little food, okay beverage, available without stopping. Ever look to jump start a German car in the hotel parking lot that is hosting the Buick GS club national meet?
"The gas pedal wouldn't go to the floor if it weren't meant to be there"
whatever you do do not just wire it up in parallel.
anything large enough to be worth the effort will 'fight' the primary battery.
in essence they will take turns dragging each other down in voltage (or trying to charge up the other one) when the car is off, and you'll kill both of them (although maybe if lucky just the secondary) in short order.
Been there and even matched twins don;t last more than a couple of years or three, even with daily driving.
Use an isolator wired to ignition. Then the battery is only connected when the key is on, ie driving, starting, etc. IF you drain the primary and the secondary is large enough you'll get a couple of chances to start the car when you flip the ignition on which connects them together again.
Ignition lead on alarm prewire cars is in the 12 pin alarm connector, and readily accessible.
Again this is only useful if you are going to be having a lot of key off accessories ( like the lighter/power port always in use, the BMW phone or the vent timer) running, or plan on running a large load in accessory (large amp draw amplifiers for example).
It is kind of a built in jumper cable. it isn't for more key off time.
Last edited by ladiesman217; 01-22-2009 at 07:15 PM.
Attack Eagle's alter Ego.
Ross, some e32s had an actual refrigerator option. coils, condensor, freon, i forget if they ran off an electric compressor or the engine compressor. Leaning towards engine compressor, but been a while since I read the install .pdf
Probably still archived on AE's .pdf collection.
Attack Eagle's alter Ego.
Super Moderator
yes, BMW had them for the E32, even one for the center concole, maker was WAECO. that was with compressor and run by electricity. See here pics from Herby under der Kuehlschrank
http://freenet-homepage.de/Herbie01/
That was a standard accessory from WAECO, and there should be a TI = technical info or EBA Einbauanleitung = installation instruction for that in the CD.
http://www.7-forum.com/forum/14/neua...6-a-65258.html
The Highline version is different, that has a complete separate cooler system driven by compressor
http://bmwe32.masscom.net/johan/ihka/ihka.html
and if you have 2 batteries, do the installation of that system as per the TI I posted earlier.
you can't do parallel or else the secondary and primary will discharge each other as they try to find a common voltage and amperage float point.
You must have an isolator.
Last edited by shogun; 01-22-2009 at 09:44 PM.
Major Contributor
understood... that is why i want a second battery that is isolated from the main system but that will charge. i like 520ise's unloader relay rig thing but i don't know if i ever want to go anywhere near the unloader relay again... (charge trek VII) i have one that plugs into the lighter socket and the draw isn't so bad, but it's tiny. that's the idea... not 24/7 but just enough for milk in my coffee if i am camping, maybe a bevvy or 2, stick o' butter, u get the idea.Originally Posted by Ross
main purpose is to switch it on to unlock the doors when batt#1 dies (methinks it's dead right now) so i can pop the hood and boost... or just a straight boost... i seriously never want to do that license plate light thing ever again and i hate crawling under the car to get to the starter. believe it or not i hate working on cars.
heyyyy... what happens when the obc alarm is set and the battery dies enough to get no start but still power the obc? i think i will find out soon...
great link shogun u r like god to me. (but i am an atheist)
Major Contributor
oh man i am so dumb sometimes
Green Beret Special Ops
Tim you have to sort this problem soon, you have like 3 more months of winter hell there, this is mind numbing that your battery dies this fast. As a temporary solution have you considered a battery tender or such to keep it topped off so you can get in and start every day?
95 E34 530I V2.37
===========
Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy
Green Beret Special Ops
Amazing theory except the E31 comes factory with 2 batteries. Problem is that the E31 drains so much upon being parked that the need to charge within a month is required whereas the E34 does not. Batts are matched and "at least" 5 years old so that part holds no grounds on my personal vehicle.
whatever you do do not just wire it up in parallel.
anything large enough to be worth the effort will 'fight' the primary battery.
in essence they will take turns dragging each other down in voltage (or trying to charge up the other one) when the car is off, and you'll kill both of them (although maybe if lucky just the secondary) in short order.
Voltage and amperes are just as stated and will charge as required without any trickery, 2 batteries are better than one in a less then adequate environment.
Been there and even matched twins don;t last more than a couple of years or three, even with daily driving.
see above 5 year claim.
Use an isolator wired to ignition. Then the battery is only connected when the key is on, ie driving, starting, etc. IF you drain the primary and the secondary is large enough you'll get a couple of chances to start the car when you flip the ignition on which connects them together again.
Ignition lead on alarm prewire cars is in the 12 pin alarm connector, and readily accessible.
You do know about circuits and my boy would be proud.
Again this is only useful if you are going to be having a lot of key off accessories ( like the lighter/power port always in use, the BMW phone or the vent timer) running, or plan on running a large load in accessory (large amp draw amplifiers for example).
It is kind of a built in jumper cable. it isn't for more key off time.
Agree the vent timer is a big drain but if not used in excess an additional battery should simply not be required in said vehicle.
95 E34 530I V2.37
===========
Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy
Major Contributor
no it's not what you think... battery is holding charge now. when it gets this cold my starter is really really slow i am amazed it catches but it always does. i am sure it is the corroded wire... it's just i haven't touched the car in 2 weeks and i suspect i will need 100% charge to get it going and it's been sitting in -20'c the whole time. i haven't needed a boost yet this winter, i keep the obc on the voltmeter all the time and make sure it never ever goes below 13.5v. if it gets worse i will borrow a garage for a day but otherwise i'm trying to keep my 'all outdoors' streak going and waiting for spring.
i have considered a solar panel but then i hit the snooze button, besides i blew all my car budget for '08/'09 in '07... have to wait for a sale
thanks for the concernsorry for the hijack
man i really am dumb
Posting Permissions
Reply With Quote