Thanks Veeeight. Appreciated.

 

When connecting a Ctek MXS 5 using the clamps, do you clamp on to the battery terminals or the provided contact points provided? Also, if i wanted to permanently connect the eyelet Ctek cable to the battery, what is the correct sequence for disconnecting and reconnecting the battery? Is there any electrical items / systems in the car that will need any sort of code or setup? Thanks.

 

When using the clamps, I connect the red clamp to the red positive connection point, underneath the red sliding cover, then place the black negative clamp to the earth bolt on the car body.
To disconnect, remove the black negative first, followed by the red positive.
I have the eyelets connected, just loosen the red positive bolt on the battery and position the bolt through the eyelet, I didn’t remove the terminal. Then wire the negative end to the car earth point on the car wing.

 

Then wire the negative end to the car earth point on the car wing.

The post on mine is brass and round, IE no place to fit a wrench. How did you remove it to attach the quick connect from Ctek?

 

That's strange! Mine is a brass nut. Just used a ordinary spanner! 12 or 13 mm. Cant remember precisely. I'll check tomorrow.

 

Just used a ordinary spanner! 12 or 13 mm.

You're quite right. 13mm. Round where it meets the fender, hex at the top. Must get my specs checked.

 

Mine goes to critical after like a week of not being used. But I'm sure theres alot of life left in the battery, maybe its just to get you to charge/run the battery to stop it being damaged. I left my old A200 about 3months in the 2020 lockdown without starting and it started fine after being on critical for 2 and a bit months

 

Today I used my ctek mx5.0 on the A45S for the 1st time, it has been on for around 5 hours and when I last checked it was on stage 7. The car alarm started going off without hazard lights and I was unable to stop the alarm, I unlocked the car and it still was going off, I then disconnected the Ctek charger but alarm still sounding, I then started the engine and it still would not stop, I then pressed the mercedes me button, after about 30 seconds while waiting to be connected the alarm finally stopped.
Was this episode due to the charging or charger in any way?
I have checked the mercedes app and there is no mention of an activation of the alarm in the alarm section?
Any advise is much appreciated, thanks.

 

Did you have it in “recondition” or deep discharge mode on the CTEK?

Never had any such issues when charging from a ctek in normal charge mode.

 

Did you have it in “recondition” or deep discharge mode on the CTEK?

It was in Car and AGM mode.

 

Just try it in car, no AGM mode next time.

it could be completely unrelated, eg the bonnet close switch slightly corroded or not making properly, the alarm sounder has its own battery backup etc.

 

Update.
Had my car in for its 1st service this week, they looked into the alarm issue that I had back in January and they have replaced the alarm siren.

 

Second alarm issue noted on this forum this year.

Alarm Siren not sounding after activation

Hi guys, hoping someone can help? Had the car since Wednesday, locked the car today with the dog on the back seat and forgot to disarm the internal sensors. When we got back to the car the hazard lights were flashing madly away but no alarm siren. Thought strange, so opened the window, locked...

www.aclassclub.co.uk

 

I’ve not been using my 180d very much this winter. I’ve got a smart charger and I was going to charge the battery once a week or so. Will this regular external charging have any detrimental effect on the battery?
cheers,
Dai

 

It's almost mandatory to use an external charger with the W177 if you don't use the car much!
But do make sure it's an intelligent charger such as a CTEK, see above.

 

Depends on the charger. If a modern maintenance/recovery charger then no, but unless you start getting battery warnings then I wouldn't bother, and even then it starts raising them long before it will fail to start assuming it is charging OK.

If you use one of those then no more than once a month at most I'd say, they can take a couple of days to do a complete cycle. I know people leave them on permanently, which is fair enough if they are going to be away for several months, but they can hide the symptoms of a failing battery that can let you down if it's not been on charge immediately before.

The old-fashioned trickle chargers are probably not a good idea to use with modern batteries.

 

Many thanks, this the charger I use.

BUDDYGO Car Battery Charger, 12V/24V 8Amp Intelligent Automatic Battery Charger/Maintainer Delivers 3 Stage Charging, with LCD Screen And have 6 Charging Mode, Suitable for More Types of Batteries

will this do the job.

 

The CTEK MXS 5.0 states that it is suitable for lead acid and Advanced Glass Mat batteries, which I think the originals on these cars were. I can see a reference to 'lead acid' on an advert for a Buddygo charger, but not the other type, so I couldn't say.

 

thanks.
Yes it has an AMG mode.

 

For those that have purchased the MXS 5, can someone tell me how long the cables are. I would like to know the length of cable that runs from the plug socket to the charging unit.

Many thanks in advance!

 

1m40cm. power plug to unit.
1m10cm unit to connecter
35cm. battery eyes to connecter
45cm. Croc clips to connecter

 

Has anyone rejuvenated their battery using the recondition mode. Especially in winter conditions.

 

For completeness I’ve ordered a charger off Amazon. We’ll see if it’s as good as advertised.

 

CTEK MXS 5.0 is a brilliant piece of kit and I used it regularly on my old A35 and am still using it on my current BMW M135i 👍

 

I watched their video and the one for the charger I ordered and both seem good. But I wouldn’t leave either on while on holiday 🤷‍♂️

 

^ +1 Yep. There’s a reason why CTEK is highly regarded in the automotive maintenance world.

 

^ +1

We use around 20 CTEK chargers of various current charging capacities at work commercially, and they are left connected at all times to both vehicle and leisure batteries 24/7/365 whenever the vehicles are parked.

Plus if it’s good enough for Harry and his vast collection of classic cars in his garage, it’s good enough for me

 

Thanks for the reassurance 👍

 

I’m not sure I would be that confident in an unknown brand charger of unknown origin and development though

 

I’m not trusting it beyond the time I am around to make sure nothing catches fire. Although both charger types are available widely.

 

Good news. My new charger fully charged the battery in around 3 hours. I am quite impressed by it and it may well defer the need for a new battery 👍. It also showed the battery was 80% charged before it started.

 

It also showed the battery was 80% charged before it started.

It may well show SOC….

but extremely doubtful that it will measure SOH which is the important metric re aged batteries.

To test the true state and capacity of a battery you’d need a proper discharge tester.

ACT 612 6V/12V Lead Acid Intelligent Battery Tester - ACT Meters (UK) Ltd

Take seconds to identify low capacity lead acid batteries with the innovative ACT 612 Intelligent Battery Tester for 6V and 12V SLA, GEL and car batteries.

www.actmeters.com

As recounted many times on the forum, no-load voltage on its own is a poor indicator of battery health.

So your “fully charged” battery may well be “fully charged” but only to say 60Ah instead of the 80Ah it was when new.

 

My main metric will be if the start/stop is active tomorrow 😂

 

…… or in a weeks time …..

 

I must admit that my battery check consists of leaving the start/stop function on until it becomes active and then switching it off. If that didn’t happen then I’d be asking the dealer to take a look at the battery. It hasn’t happened yet on my 21 plate W177 but it did on my previous W176 and when they checked they replaced it under warranty no questions asked.