2014CL600

Could someone tell me where the aux battery is on the C217 S550 4MC? I’m not interested in any stories or where you think it is on your S63 or S65 , A217 Cab, S Class 4dr or any other model. I know I sound rude and harsh and I apologize but I never get a straight forward answer, when I ask a straight forward question, about a specific model that I’m dealing with at the time. This is no disrespect to you who don’t own a C217 but please be brief and to the point on location. Also, please no guesses. I’d like to only hear from people that own an S550 4MC from 2015-2017. Thank you and again, I apologize if I sound rude, it’s not meant to be.

cyberay

I own a 2015 since new and have changed the auxiliary battery twice, most recently about 3 months ago. I assure you it is in the trunk, right rear, behind the fuse block. It’s best to buy the MB battery if you are keeping the car. $175 at the dealer.

2014CL600

Thank you!!! Funny thing is, I special ordered mine in 14, I’m still on my original batteries. Yesterday , it just blinked Auxiliary battery malfunction. I ordered one last night and it will be here Monday. My main battery is still at peak performance. The message hasn’t come back but I’m thinking it’s on its way out. The replacement is the newer AGM style. Thank you for your direct answer.

haa

I remember seeing it is on the passenger side of the trunk in the coupe and under the passenger side rear seat in the cabriolet.