Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
On this model your brake system is a electronically controlled brake system called the SBC brake system.This system uses its own battery which is located on the passenger side under hood usually under the combination filter.This battery is very small.If this battery fails or the SBC control unit fails or any of the brake sensors not related to the brake pad wear sensors, fails then this can cause this light to come on like you see here.
What has to be done is to have the fault codes read out/checked using either a fully compatible scan tool that will plug in and can read all computers in your vehicle to see what codes are set or a dealers sds machine plugged into your vehicle.
Once this is done the codes are then diagnosed to locate and repair this issue here.The esp message and brake light are both related with the same fault that is occuring causing both of these messages to come on and the codes do need read out to help locate which component needs replaced.
If it is the SBC control unit I know in the past Mercedes extended the warranty for life on it and a dealer would replace it at no charge to you.
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