Battery kill switch

[X5Sport]

Correct in that case.

[jeegnesh]

Silly question as per usual. I got the ODB 2.4 watt solar charger and result the car started 3 days later, would normally be dead. So my dad has a solar charger doing nothing is there any harm in using the 2 together so I'd use his visa the cigarette plug?

FYI - Cables and switch ordered.

[jeegnesh]

Parts still not here for kill switch.  ::)

Solar charger going back, after previous success, 24 hours later it would not start.

Note when i turn car off after a decent run, it shows 12.2v, in less then 60 seconds it drop to 11.8, then steady downwards from there, I assume its safe to say the battery is toast?

Did not see an answer if AGM battery can be dropped in no issues? If I plan to use the negative switch, does AGM or non-AGM hold charge longer doing nothing or they are the same?

[Horizon]

AGM need a larger charge voltage than lead acid batteries, hence E70's having a battery registration via software to tell the charging system if it's AGM or Lead acid.
Stick to lead acid to be on the safe side, get a long warranty one, then replace it on warranty if low use kills it

edit, sorry for the miss information

[X5Sport]

I think you mean a ‘wet or flooded’ battery as AGM are still Lead/Acid.

AGM have better self-discharge performance than conventional flooded cells and both need the correct charging system.  My E53 had an AGM battery from new and lasted 6 years at least (I sold it with the original on board).  It depends upon what BMW fitted at the time.  Some did have AGM and some didn’t though I have no idea why!  Realoem shows AGM as standard for my 2005 model year.

The E70 (and newer) have Intelligent Battery Systems which are part of the Efficient Dynamics package and also monitor battery charge-ability..... ie can they hold a proper charge.  I believe the alternator charge system also does more work on the overrun to help with fuel economy - but don’t quote me on that!

Cars with Stop/Start (like the F15] need AGM because they handle deep discharge better - though in my experience that was far from true when my Škoda battery completely failed (dropped to under 5V) at less that 2 years from brand new!

You can get 6-year Warranty AGM as well as for flooded.

@Jeeg.....yes your battery is toast if it is decaying that fast.  You have one (or more cells) dying.  You should be looking at 1 month of the car standing before the battery goes flat.

[jeegnesh]

So my logic was that as I will be using negative kill switch ALOT.  Hence new battery I buy I'd like one that holds charge for the longest duration, if there nothing much in it then obviously pleased to save the money on non-AGM.  Plan is use kill switch and plug in a solar charger via the front clamps (2.4 watts has diode to prevent reverse charge).  In hope that I don't kill yet another battery.

FYI - Tempted with the Duracell battery ECP are selling has 5 year, anyone heard anything regards Duracell and car batteries?

Switch and Cables arrived today (maybe install later today).  FYI - The cables are PHAT would recommend if anyone needs to buy, sold in loads of sizes:

https://www.ebay.co.uk/itm/48-1200mm-50 ... 2776851883

[jeegnesh]

Kill switch installed and working, not much use as the battery is too low, will wait for ECP Easter discount before I pickup the battery.

So the wires being so thick did present problems, the cable is a little thicker then the OEM lead, was tough getting 2 of them throw the metal plate and under the seat, managed that.  Also being so thick they are quite tight when taking the seat down, so they don't move easily, so screwing the switch too the back seat could be a problem.  Need to get a little velcro on the switch plate that should do the job nicely.

[lezmtaylor]

Well done, glad it works ok.

Lez

[jeegnesh]

[quote="lezmtaylor"]
Well done, glad it works ok.

Lez
[/quote]

BTW - I can’t charge via the front terminals if the switch is off.

[jaynana]

[quote="jeegnesh"]
Kill switch installed and working, not much use as the battery is too low, will wait for ECP Easter discount before I pickup the battery.

So the wires being so thick did present problems, the cable is a little thicker then the OEM lead, was tough getting 2 of them throw the metal plate and under the seat, managed that.  Also being so thick they are quite tight when taking the seat down, so they don't move easily, so screwing the switch too the back seat could be a problem.  Need to get a little velcro on the switch plate that should do the job nicely.
[/quote]

well done, and u did it urself not Sanj? lol, where are the 

[lezmtaylor]

well mine does, perhaps it is different as mine is petrol (4.4) and yours is diesel.

Lez

[jaynana]

huh? meaning your kill switch doesn't exactly 'kill' everything? - how else do the front terminals have connectivity with the battery?

[henrym3]

Surely you must loose all your presets

[jeegnesh]

Yes you lose presets, better the car starts then have presets.  Actually the worse thing is my head unit gone back to the 1960's menu system, anyway to get this back and keep it? Or will disconnecting the battery not allow this?

Duracell battery on order.

@jaynana pic for you but not very interesting and not stuck down either.  And yes I done it all by myself 

[henrym3]

So, how does this work, you open the drivers door with the key, climb over the seat, drop the rear seat backrest and operate switch or can you just reach the rear door and open it from the inside?