[derek0480]

So I store my car throughout the winter under a cover in a garage and I do try to start it up at least once every 2 weeks and let it idle for 5-10 minutes but the last 2 times I'm getting a battery charge warning light that tells me to drive for an extended time to charge it.

Problem is I'm not going to take it out on the pothole and salt ridden roads right now just to charge it and risk paint chips or a broken rim.

I know why the battery is losing power, but shouldn't it hold a charge a little better or do i just need to let it idle for longer so the alternator does its job?

Dealer said not to unhook the battery as it's powering systems even when the car is not running.

Thoughts?

2015 550i with 21k miles so the battery is still in great shape.

[mrashton]

Originally Posted by derek0480

So I store my car throughout the winter under a cover in a garage and I do try to start it up at least once every 2 weeks and let it idle for 5-10 minutes but the last 2 times I'm getting a battery charge warning light that tells me to drive for an extended time to charge it.

Problem is I'm not going to take it out on the pothole and salt ridden roads right now just to charge it and risk paint chips or a broken rim.

I know why the battery is losing power, but shouldn't it hold a charge a little better or do i just need to let it idle for longer so the alternator does its job?

Dealer said not to unhook the battery as it's powering systems even when the car is not running.

Thoughts?

2015 550i with 21k miles so the battery is still in great shape.

Leaving the engine to idle for 5 or 10 minutes is not good for the engine and is discouraged. You will do more harm than good. Idling the car is never going to charge the battery and the battery should not be disconnected.

Get yourself a battery tender such as the CTEK MXS 5.0 and leave that attached to the charge points under the bonnet while you are not driving the car for an extended period. It will fully charge the battery then continue topping up the charge and is quite safe. If not the model I mention, make sure it has a setting specifically for AGM batteries which is the type fitted to our cars.

[snj1013]

Get this one
https://www.amazon.com/CTEK-56-864-A...&keywords=ctek

[derek0480]

Originally Posted by snj1013

Get this one
https://www.amazon.com/CTEK-56-864-A...&keywords=ctek

What's the difference between the 4.3 and the 5.0?

[lsturbointeg]

car has to be driven in order for the battery to charge. letting it idle won't charge the battery at all. my car was like yours...during the winters it would sit in storage but i would make it a point to start it up and drive it around for 30 min. i hear ya about the road salt but a quick wash will help prevent any corosion

[EL Jeffe 5]

I store my car over winter as well
Letting your car idle wont do nothing but get engine warmed up and fluid moving trough engine.
Driving your car around bloc wont do nothing for your battery again it will help getting engine up to temperature and you wont have flats spots on your tires.
Now what can you do to benefit your battery is buy trickle charger and hook it up at least twice a month or more it will keep your battery healthy.

[EL Jeffe 5]

Originally Posted by derek0480

What's the difference between the 4.3 and the 5.0?

NO need for fancy BMW logo charger just go to Wallmart buy one for $15 will work just fine trust me
That's what I did I been using my for years no issues

[derek0480]

Originally Posted by EL Jeffe 5

NO need for fancy BMW logo charger just go to Wallmart buy one for $15 will work just fine trust me
That's what I did I been using my for years no issues

Appreciate it fellas. Bought one and will hook it up when it arrives tomorrow.