Cabin Filter Change, Aux battery in the way - Advice

[HITECH]

Im changing a cabin filter on a B-Class W246. UK right hand drive. I pulled up the carpet (passenger side) and took a look at the cabin filter which bizzarely sits right above an auxilliary battery. My question is what exactly is this battery for ? Can I disconnect it and remove it out the way to change the filter out without any kind of faults occuring. I ask this question because Im not entirely sure about the reason for the aux battery? What exactly is it backing up ? I had access to Mercedes WIS (document no:AP83.00-P-8384NK) which was quite laughable to be honest. The instructions on it did not have the aux battery showing in it and it showed a left hand drive car. Some info from anybody on if its safe enough to simply disconnect and remove the aux battery so i can get the cabin filter changed out would be much appreciated. Cheers.

 

[markjay]

Not sure about the B-Class, but on my W204 the auxiliary battery is small - the size of a motorcycle battery - and it's purpose is to support the various electric consumers so that the main battery keeps it's charge for the Stop/Start function.

If the auxiliary battery if faulty or disconnected then the Stop/Start function won't work.

On my car you can disconnect and reconnect the auxilary battery when ignition is off without any ill-effects.

 

[HITECH]

Ok so yes I can disconnect and remove the battery for the duration of time it takes to slide the old cabin filter out and put new one in ? Without any electrical/backup repercussions ?

Not sure about the B-Class, but on my W204 the auxiliary battery is small - the size of a motorcycle battery - and it's purpose is to support the various electric consumers so that the main battery keeps it's charge for the Stop/Start function.

If the auxiliary battery if faulty or disconnected then the Stop/Start function won't work.

On my car you can disconnect and reconnect the auxilary battery when ignition is off without any ill-effects.

 

[markjay]

This is my auxiliary battery (mine is in the boot next to spare wheel):

And as you can see it was disconnected when the photo was taken.

So if your battery is the same as mine... then the yes it can be disconnected (while the engine and ignition are off) .

 

[HITECH]

Yeh same battery but just in a different location. Bit strange to fit it obstructing a service part that requires replacing regularly according to Mercedes maintenance schedules. How stupid where it has been fitted. It must have been an afterthought and additional extra on the sports version I have to service. Thanks for taking time to get that photo. I appreciate it.

This is my auxiliary battery (mine is in the boot next to spare wheel):

And as you can see it was disconnected when the photo was taken.

So if your battery is the same as mine... then the yes it can be disconnected (while the engine and ignition are off) .

 

[Dickie Fix]

No need to touch the aux battery when changing the cabin air filter. It's a bit of a struggle, but it does come out, despite the limited space. Just grab/wiggle/pull the filter and it will come out.

 

[HITECH]

yeah I reckon it would have aswell but it would have been a bit of a squashed up mess by the time it would have got bent up into its slot.Took literally 30 seconds to disconnect and remove it anyway. Job done. Thanks a lot guys for the info and especially taking time to stick a picture up aswell. Another happy customer.

No need to touch the aux battery when changing the cabin air filter. It's a bit of a struggle, but it does come out, despite the limited space. Just grab/wiggle/pull the filter and it will come out.