[AllBlackBimmer]

I'm looking to get a battery tender... It's winter in the NE, and I just bought a truck and my e90 has been sitting in my garage untouched the last 2 weeks.

Most likely will get the BMW branded one, I know it is just a ctek unit (or deltech forget which one) with the bmw logo and premium.... Anyway...

They seem to make two different kinds... One that uses the cigarette lighter as the plugin and one with the tradition black/red clamps that connect directly to the battery...

Which one is needed for our e90s?

...also, I assume wherher it's the door or truck, there is no issue with closing either/or and crushing the wire correct? I don't want my door or trunk hanging open...

Thanks.

[parabola]

You should connect to the battery jump terminals under the front hood, not directly to the battery.

[OP3NAIR]

Connect to the jump terminals under the hood, and you can close the hood on the wire. Just make sure its not in the hood latches.

[AllBlackBimmer]

Originally Posted by parabola

You should connect to the battery jump terminals under the front hood, not directly to the battery.

Yea, sorry, this is correct, not directly to the battery in the trunk.. Wasn't really thinking when I posted earlier...

Anyway, I guess I should get the one with the clamps and not cig lighter.

[parabola]

Originally Posted by AllBlackBimmer

Yea, sorry, this is correct, not directly to the battery in the trunk.. Wasn't really thinking when I posted earlier...

Anyway, I guess I should get the one with the clamps and not cig lighter.

Yes, I'd get something that has alligator clips / clamps.

[Efthreeoh]

I'm not sure why you can't connect directly to the battery terminals, which is what I would do. I get it that the IBS and BST are basically on the battery posts, but I see no difference in the power coming down from the hood terminals. The Deltran unit comes with a harness that allows direct, permanent connection to the battery terminals that you can connect right to the clamp hold-down bolts. Not sure why you'd want to run the power all the way back to the battery from the trunk since it could slightly change the way the unit monitors the battery.

Just some thoughts.

[parabola]

Originally Posted by Efthreeoh

I'm not sure why you can't connect directly to the battery terminals, which is what I would do. I get it that the IBS and BST are basically on the battery posts, but I see no difference in the power coming down from the hood terminals. The Deltran unit comes with a harness that allows direct, permanent connection to the battery terminals that you can connect right to the clamp hold-down bolts. Not sure why you'd want to run the power all the way back to the battery from the trunk since it could slightly change the way the unit monitors the battery.

Just some thoughts.

You can probably hook it to the battery without problems, however, I'd rather do it from the engine bay since it's rather easy to connect and there is less chance of damaging IBS. Lines from the battery jump terminals should be of substantial size and it's a short distance, so voltage drop should be minimal. After all, circuit is designed to handle high current loads during jump starts and to limit the power input to the battery to prevent overcharging or voltage spikes or some other anomalies.

If you connect directly to the battery, would you disconnect battery terminals completely before hooking up the charger or leave them on? Not sure how IBS behaves if you leave terminals and battery charger on directly on the battery..

[Efthreeoh]

Originally Posted by parabola

You can probably hook it to the battery without problems, however, I'd rather do it from the engine bay since it's rather easy to connect and there is less chance of damaging IBS. Lines from the battery jump terminals should be of substantial size and it's a short distance, so voltage drop should be minimal. After all, circuit is designed to handle high current loads during jump starts and to limit the power input to the battery to prevent overcharging or voltage spikes or some other anomalies.

If you connect directly to the battery, would you disconnect battery terminals completely before hooking up the charger or leave them on? Not sure how IBS behaves if you leave terminals and battery charger on directly on the battery..

I'd leave them on. My issue is the Tender is going to "see" the resistance of the long cables, which may affect how it treats the battery.

[chillbil79]

http://www.amazon.com/Deltran-Batter.../dp/B00068XCQU

Pop hood, hook it up to connections, go drink a beer

Done!! Simple as that. Thread closed

[BMWinAZ]

Originally Posted by chillbil79

http://www.amazon.com/Deltran-Batter.../dp/B00068XCQU

Pop hood, hook it up to connections, go drink a beer

Done!! Simple as that. Thread closed

I have used this battery tender for a number of years on our X3 and 328i for two months every summer. I hook them to the connections under the hood. They work great with no ill effects.

[parabola]

I did a bit of digging on this subject through the BMW service documentation...read at your pleasure

[AllBlackBimmer]

After I hooked up the tender, and say I want to drive the car a few days later... Just pop them off and start car normally?

No issue with putting my car on and off the tender?

I'm not storing my car long term, I just don't want to drive my car when it snows or tons of salt on the road, but I'd still drive it once or twice a week even if it's just cold.

Reason I want a tender is, I started my car today for the first time in two weeks and it struggled. Took it on a 40 min highway drive right after. It has been below 20-30 degrees for over a week which is why I really want a tender.

... Anyone know any venders or dealerships running promos or discounts?

[chillbil79]

Originally Posted by AllBlackBimmer

After I hooked up the tender, and say I want to drive the car a few days later... Just pop them off and start car normally?

No issue with putting my car on and off the tender?

I'm not storing my car long term, I just don't want to drive my car when it snows or tons of salt on the road, but I'd still drive it once or twice a week even if it's just cold.

Reason I want a tender is, I started my car today for the first time in two weeks and it struggled. Took it on a 40 min highway drive right after. It has been below 20-30 degrees for over a week which is why I really want a tender.

... Anyone know any venders or dealerships running promos or discounts?

Your fine

Buy the tender I showed in link. I drive my BMW on weekends and barely in winter months

No issues with taking it off and on tender. My BMW is 2008 and on same battery

[riczon.335i]

I purchased a Deltran Battery Tender from Costco. I have it hooked up under the hood, I don't drive it much during the winter, I usually just unhook and drive off then after all the fun is over I just hook it right back up and she sits for another few weeks to a Month depending on weather.

No issues whatsoever!
I have 2007 e92 335i still on original battery with 35k miles.

[stevenh44]

I recommend ctek 4.3 battery charger/maintainer

[AllBlackBimmer]

Originally Posted by chillbil79

Your fine

Buy the tender I showed in link. I drive my BMW on weekends and barely in winter months

No issues with taking it off and on tender. My BMW is 2008 and on same battery

Ok thanks...

Sry for so many questions, but that's just how I am.... But just hook it up and good to go? Don't have to do anything special right?

If you drive your car that little... How often do you have yours hooked up?

I will def use the under the hood connection...easily accessible I assume... No covers or anything? Red to red, black to black and done... Can you latch the hood when connected or does it just just to be slightly open?

My car is garaged, but my garage is not insulated and not heated... No issues with the deltran changer hooked up in cold weather?

[riczon.335i]

Originally Posted by AllBlackBimmer

Ok thanks...

Sry for so many questions, but that's just how I am.... But just hook it up and good to go? Don't have to do anything special right?

If you drive your car that little... How often do you have yours hooked up?

I will def use the under the hood connection...easily accessible I assume... No covers or anything? Red to red, black to black and done... Can you latch the hood when connected or does it just just to be slightly open?

My car is garaged, but my garage is not insulated and not heated... No issues with the deltran changer hooked up in cold weather?

Yes pretty much just hook and let sit, also would like to add my connection was not red to red or black to black it had reverse polarity but it might vary on your car. I can take pics on how mine is set up in my garage.

My Garage is not heated or insulated very well but like I stated no issues. You can close the hood just enough for clearance of all the wires and connectors.

[AllBlackBimmer]

Originally Posted by riczonh

Yes pretty much just hook and let sit, also would like to add my connection was not red to red or black to black it had reverse polarity but it might vary on your car. I can take pics on how mine is set up in my garage.

My Garage is not heated or insulated very well but like I stated no issues. You can close the hood just enough for clearance of all the wires and connectors.

Yea,I'd be interested to see your connection..I'm not really sure what you mean when you say your car had reverse polarity? ... I have an '08 328 sedan...

Oh, and how long are the cables?

I'm doing some googling now,mans seems some guys,like the CTEKs better, but is mostly a toss up...mid prob get the deltran just because that's what BMW uses as theirs.

[ctuna]

ctek 3300 or better usually recommended here
more than any other . See what J has to say.

[Jamaro]

I use a Deltran, connected under the hood. Works great.

[riczon.335i]

Originally Posted by AllBlackBimmer

Yea,I'd be interested to see your connection..I'm not really sure what you mean when you say your car had reverse polarity? ... I have an '08 328 sedan...

Oh, and how long are the cables?

I'm doing some googling now,mans seems some guys,like the CTEKs better, but is mostly a toss up...mid prob get the deltran just because that's what BMW uses as theirs.

Here's some pics! What I meant by reverse polarity was mine is hooked up black to red and red to black. See photo!

[riczon.335i]

Pics