Trickle charger for M6

[matt21]

I’m barely using my 2017 M6 at the moment, so looking to get a trickle charger to preserve the battery. Would also like to use it on some more mainstream older cars too. Will be in garage or under a car port.

Any recommendations? I’m looking at CTEK but not sure which to get for something like an M6

Cheers!

[nw942]

I went for the MXS 5.0 and it has worked fine on a variety of cars as a trickle charger.

One of the reasons I went for it is that it had a recondition mode, but that has not worked very well for me on a flat battery as the charger throws an error. I have had to put a dumb charger on the battery for a few hours before the CTEK will start the recondition mode.

So in hindsight I should probably have gone for the 3.8.

[Scrump]

CTEK is one the most recommended brands on here.
The 3.8 or the 5.0 will be fine for your car. I have a 5.0, but it cost about the same as the 3.8 in the sales.

[theboss]

I just bought the CTEK unit OEM’d by BMW for my F10 M5

I figured if I fried anything when connecting it BMW would be obliged to help and also it’s rated for Li-on as well as all the lead acid battery types so would be future proof if I decided to swap for a newer M car.

[matt21]

Thanks. Do you have a link of any info on the BMW CTEK?

[Shanksy87]

Another vote for CTEK, I have a MXS 3.8 and a 5.0 that i've used for 6+ years now without fail.

The BMW labelled CTEK will be one of their most basic models offering less functionality but for more money. Battery's are my job and they are not complex beasts. Just make sure whatever you select can handle your type of battery, which in the M6 is AGM I believe. The MXS 5.0 is best for this as it does the regular flooded and AGM, and reconditioning if you let the cell go down too far.

[theboss]

matt21 said:

Thanks. Do you have a link of any info on the BMW CTEK?

https://shop.bmw.co.uk/bmw-uk-responsive/en_GB/p/-/bmw-battery-charger/2408593/

There was £10 discounted when I bought one - try adding to w basket and checking out to see if they are still doing it

As I said above I wanted some assurances as a BMW supplied device certified as being good for all M vehicles and I like the fact it would work on lithium batteries also - the regular CTEK didn’t state this

It supplies 5A

[matt21]

Thanks guys, very helpful. The BMW wasn’t as expensive as I thought, and maybe a good option as I can use on a few different BMWs in the family.

What is the difference though between the more basic CTEK BMW charger and MXS 5.0?

[theboss]

I couldn’t tell any difference and they were the same price

The BMW has the 8 stages with LEDs.

There isn’t a recondition button but apparently this isn’t intended for AGM from what I read.

BMW states it’s good for lithium (F90 onwards) which CTEK don’t mention.

Can’t fault it so far but then I didn’t have a dodgy battery to begin with so I can’t tell any difference. I bought it preventatively.

One bit of advice. Use the + terminal under the bonnet. Apparently it’s not good to connect to the battery terminals - the cars electronics don’t like it. According to various people online. Haven’t fished out the manual to confirm but the designated terminal seems like the right way to go.

[JMBMWM5]

theboss said:

I couldn’t tell any difference and they were the same price

The BMW has the 8 stages with LEDs.

There isn’t a recondition button but apparently this isn’t intended for AGM from what I read.

BMW states it’s good for lithium (F90 onwards) which CTEK don’t mention.

Can’t fault it so far but then I didn’t have a dodgy battery to begin with so I can’t tell any difference. I bought it preventatively.

One bit of advice. Use the + terminal under the bonnet. Apparently it’s not good to connect to the battery terminals - the cars electronics don’t like it. According to various people online. Haven’t fished out the manual to confirm but the designated terminal seems like the right way to go.

Yep correct connect under the hood.

[matt21]

Thanks again.

Do you know if the BMW is good for use on non AGM batteries too? Looking to use on my old Passat too

[helix402]

matt21 said:

Thanks again.

Do you know if the BMW is good for use on non AGM batteries too? Looking to use on my old Passat too

Pretty sure it will be.

[Ninja59]

It is good for AGM batteries the description says so, and my 640D is kept on a trickle after not seeing much use in 2020.

What I will say though to anyone purchasing one is the first time you use it (or need to change modes) plug it in to the wall socket disconnected from the car , select the right mode and then turn the unit off.

Once you have done that get it setup on the car and then leave it.

Also think about placement of the unit the cables are not exactly significant in terms of length, but lucky for me my sparky had put a socket right next to the bonnet points...wall mounted the trickle charger and the car sits absolutely fine until I need the car.

Do remember to lock your car before turning the unit on, on the F06 you can get away with leaving the bonnet just on the safety catch without issue .

In regards to the unit my first unit failed after not many months use, which was annoying, if you need a replacement be prepared for a bit of a faff. BMW warranty will ask for the unit to be tested first before supplying a replacement (I got my dealer to order one in before they had done the test wasting time for a tech to check it was fubered).

[TNW]

Did anyone else have an issue completing the purchase on the website? I just tried and when I clicked to confirm the order at step 4 it just went back to step 2.