Battery kill switch, which one and where in car ?

[Rombbb]

For long term storage of e86.

There are master switches that hook up on the battery itself. Probably the easiest route but a bit annoying removing the battery cover each time.

Not a track car so can't just drill holes in the interior with a big red switch. I thought maybe somewhere in the engine bay, but would like to still be able to connect trickle charger to the battery +/- connections in the bay, while battery is disconnected from the rest of the car.

Not sure that's possible.

Anyone good ideas / product suggestions ?

[Salty Dog]

Trickle charger?

[Don L]

Use this. Plugs into cigarette lighter plug in ash tray. http://www.batterytender.com

Don

[Rombbb]

Originally Posted by Salty Dog

Trickle charger?

Thanks, yes will do trickle but thought it best to simply also cut car electronics if long not in use, but probably I'm fuzzing over nothing.

Will maybe put this on :

https://www.grandado.com/products/au...SABEgLPRvD_BwE

[Rombbb]

Originally Posted by Don L

Use this. Plugs into cigarette lighter plug in ash tray. http://www.batterytender.com

Don

Thanks, looks good, just ordered the Noco G3500 earlier today

[Salty Dog]

Originally Posted by Rombbb

Thanks, yes will do trickle but thought it best to simply also cut car electronics if long not in use, but probably I'm fuzzing over nothing.

Will maybe put this on :

https://www.grandado.com/products/au...SABEgLPRvD_BwE

I have two older cars, a 79 Mini (my wifes car) and a 96 Porsche 911. Both go away around the beginning of November and don't come out until about the end of March. Both just go on a trickle charger. Never an issue, I find if you keep the battery on a trickle charge (tender) they last longer before they need to be replaced.

[Rombbb]

Originally Posted by Salty Dog

I have two older cars, a 79 Mini (my wifes car) and a 96 Porsche 911. Both go away around the beginning of November and don't come out until about the end of March. Both just go on a trickle charger. Never an issue, I find if you keep the battery on a trickle charge (tender) they last longer before they need to be replaced.

Thanks, for sure the trickle extends baterylife especially in low temps. At least thats what I read everywhere.

But BMW Z4 Manual does say to disconnect the battery if storing >3 months, so hence I'd like a cut off switch, to avoid wrenching the clamps each time.

[Salty Dog]

Originally Posted by Rombbb

Thanks, for sure the trickle extends baterylife especially in low temps. At least thats what I read everywhere.

But BMW Z4 Manual does say to disconnect the battery if storing >3 months, so hence I'd like a cut off switch, to avoid wrenching the clamps each time.

When I had my Z4MC I just put it on the tender, my bad I guess but I never had any issues. Mind you I'd usually start it up once a month, bring it up to temp and move it up and down the driveway. I know there are lots of different views on how to put a car away for the winter months and many would say that was wrong but some say it's ok. That was just my thing.

[Efthreeoh]

Just want to be precise here. I think Salty is referring to a "battery maintainer" and not an actual trickle charger. There is a difference. Trickle chargers slowly and constantly charge an auto battery, and if left on the battery for a long period of time can eventually boil off all the acid. The term "trickle charger" is a bit out dated and is a device that is a slow-rate charger versus a fast-rate charger that many service shops use to rapidly recharge an auto battery.

A battery maintainer controls the voltage level of the battery and maintains the proper state of charge of the battery without over-charging it.

That said, Salty's advice is spot on. OP, just get one of the several brands of battery maintainers, hook the leads up to the under-hood terminals either with the alligator clips most units come with, or the permanent pigtail leads that can be affixed to the under-hood terminals. Most brands come with both types of leads. IMO, I think most modern cars do better with attaching a battery maintainer to the vehicle rather than leave the control modules and other electronics without electric power of long periods of time.

[Salty Dog]

Originally Posted by Efthreeoh

Just want to be precise here. I think Salty is referring to a "battery maintainer" and not an actual trickle charger. There is a difference. Trickle chargers slowly and constantly charge an auto battery, and if left on the battery for a long period of time can eventually boil off all the acid. The term "trickle charger" is a bit out dated and is a device that is a slow-rate charger rather than a fast-rate charger that many service shops use to rapidly recharge an auto battery.

A battery maintainer controls the voltage level of the battery and maintains the proper state of charge of the battery without over-charging it.

That said, Salty's advice is spot on. OP, just get one of the several brands of battery maintainers, hook the leads up to the under-hood terminals either with the alligator clips most units come with, or the permanent pigtail leads that can be affixed to the under-hood terminals. Most brands come with both types of leads.

You are correct, I'm old school. I always referred to them as trickle chargers, but a battery maintainer is what I meant.

[Efthreeoh]

Originally Posted by Salty Dog

You are correct, I'm old school. I always referred to them as trickle chargers, but a battery maintainer is what I meant.

Yeah, me too. Old school because I'm.. well... I'm OLD (doctor confirmed ). I just wanted to be clear in case a fresh out reads the thread and gets the wrong device. Heck, I'm not even sure they are still made.

[wdb]

Many modern battery chargers do both recovery charging and maintenance charging. I use CTEK brand, MUS 4.3 specifically, and I'm very happy with them. I even recovered the battery in my E93 with one, which easily saved the cost of the charger.

[Rombbb]

Originally Posted by Efthreeoh

IMO, I think most modern cars do better with attaching a battery maintainer to the vehicle rather than leave the control modules and other electronics without electric power of long periods of time.

I do tend to agree, but then again the manual says to remove the battery if storing >3 months and you know how thorough ze germans are :-)

Just a bit confusing.

Wouldn't it actually slow down degrading of electrical components if there is no power to them at all ?
Or does that potentially mess with the delicate (im)balances in tiny transistors etc.

Thanks for feedback to all by the way, appreciate it

[Efthreeoh]

Originally Posted by Rombbb

I do tend to agree, but then again the manual says to remove the battery if storing >3 months and you know how thorough ze germans are :-)

Just a bit confusing.

Wouldn't it actually slow down degrading of electrical components if there is no power to them at all ?
Or does that potentially mess with the delicate (im)balances in tiny transistors etc.

Thanks for feedback to all by the way, appreciate it

I'm not saying that disconnecting the battery will damage the various Z4 control units, but I seem to remember reading for the E90 at least, that leaving the battery out for long periods of time can screw up some of the accounting routines in the CBS and mess up the service intervals. The Z4 CBS is one generation back from the E90, so it may not matter.

But over the 30 or so years I've kept batteries on a maintainer (mostly brainless motorcycles and my diesel tractor), the batteries have lasted very long periods of time.

[Rombbb]

Learning moment : what is the CBS ?

(Googling didn't really help out )

[Efthreeoh]

Originally Posted by Rombbb

Learning moment : what is the CBS ?

(Googling didn't really help out )

Condition-Based Service. The car uses sensors, and/or time-based algorithms to notify you of maintenance items due. The E86 Coupe really just has engine oil change notification and Inspection I & II notifications. Other BMWs, especially ones a decade newer have more sophisticated CBS systems; while at the same time dropping the maintenance technical data published in the manual set that comes with the car...

[Rombbb]

Originally Posted by Efthreeoh

Condition-Based Service. The car uses sensors, and/or time-based algorithms to notify you of maintenance items due. The E86 Coupe really just has engine oil change notification and Inspection I & II notifications. Other BMWs, especially ones a decade newer have more sophisticated CBS systems; while at the same time dropping the maintenance technical data published in the manual set that comes with the car...

Nice, thanks !

[rsutoratosu]

I left my battery off one winter (nov - march) while parking in garage with no outlets.. 0 issues.