[moldcad]

As my sig says, I have - besides my beloved M235i which I use for long business trips - also the Golf mk7 R, which is my wifey's DD (plus my AWD in case of snowy winters, as well as a toy when I just feel like driving it instead of the M235i). My wife only uses the R on short distances around the city, so I must charge its battery from time to time - of course I'd like to buy a battery tender good for both vehicles... I did some research an know that my BMW battery is an 80 Ah, VRLA/AGM one, while the R's - a 69 Ah in EFB technology one. I guess both the CTEK MXS 5.0 and the BOSCH C3 would be good for the purpose - but can anyone advise which of the 2 to pick and why (CTEK is 50% more expensive)? TIA!

[horsepower_and_hounds]

I use the battery tender I used to use on my track bike...it is a smart charger. Just plug it on and go

[Pyewacket69]

I have used CTEK battery tenders for years with great success.

In the one incident I had in which one of the Chargers died (several years old), I called the support group, and they instructed me to send it in for examination. A couple of weeks later I received a brand new unit in the mail, no charge...

It's hard to find companies that stand behind their product like that nowadays.

[moldcad]

Yeah, I'm also tempted by CTEK's legendary quality and support... I guess two cars like mine deserve the best! On the other hand, Bosh has become a very much "globalized" company lately so it'd probably be made in China, while CTEK is said to be all Swedish.

Decision made; thanks guys.

[overcoil]

^^^^

CTEK on Jay Leno Garage

[NEUE02]

I have 4 different types of chargers and the CTEK is the one I like best.

[Spaghetti]

Love my CTEK 7002 - have been using for many years.

[moldcad]

OK, so - in spite of so many positive feedback for the CTEK - I purchased the Bosch C3 tender (50% cheaper), and have just successfully completed topping-up my R's 69AH EFB battery (it needed charging badly, as my wife - using the R as her DD - only drives short distances in the city). I used "Mode 3 | 12 V (14.4 V / 3.5 A), suitable for batteries with a capacity of more than 14 Ah in normal condition".

However, I need advice on which mode of the Bosch C3 to use with my M235i's VRLA/AGM battery. Should it also be mode 3, or "Mode 4 | 12 V (14.7 V / 3.5 A) suitable for batteries with a capacity of more than 14Ah in cold condition or for many AGM batteries"? But then, how do I know whether my VARTA 80 Ah VRLA/AGM battery in the BMW belongs to the "many AGM batteries" mentioned in Mode 4 description for the Bosh C3 charger? And using higher voltage and current then necessary can be destructive for any VRLA battery - AGM or not - especially when the ambient temperature is what we have now (well over 30C)... Please advise; TIA.

[Pyewacket69]

Wish I could be of assistance, but I'm a CTEK user and not familiar with your charger.

Why not send an email to their support group with your specifics and see what they have to say?


Bosch is a good name, but I hope the few $$$ you saved today don't come back later on to bite you in the butt.

[moldcad]

I ceratinly hope so, too. The Bosch has been straightforward with my R's EFB battery; also the "BMW" charger is actually a rebranded CTEK, and yet my SA couldn't answer my questions on what a VRLA/AGM battery I have in my M235i really is... So, I just used the same mode (3) as for the R, as it charges to 14.4V like the BMW/CTEK, and not at 13.8V like mode 4 does. So - until I get a definite answer - I guess it's safer (the same voltage as with the BMW/CTEK, 3.6 A vs. 5 A of the CTEK - so if anything, mode 3 could be a bit slower, but - I hope - safe for my BMW battery....