I need some help with figuring out if it is my EIS or ESL that is going out on my car. I have a 2011 C63. I just purchased this car a month ago from a used car dealership with 69K miles. The other day I get ready to leave work I go to press the start button and the dash lights go out as if my car just lost all electrical power. Windows didn't roll down or up, the trunk wouldn't open, locks didn't work. The car just lost all electrical power. About 10-15 minutes go by and the car suddenly has electrical power again. I got to start and the same thing happens and all power is lost. I try one more time and the car starts up as normal. I drove it home, turned it off and on a few times when I got home and it started back up with no issues. I later go to the store and the car works and starts fine with no issues.

Next day(TODAY): I drive to work, Take my lunch and when I get back in my car from where I was eating to head back to work the same thing happens. Loss of all electrical power. I try starting it several times and nothing. I wait a few minutes and it starts up like normal. After work, I ran some errands before I made it home and it started every time with no issues. So my question is does this sound like an EIS going out? Or does this sound like an ESL issue? Mind me I use the push button start and not the key to start the vehicle. I did check the battery with the car off and the battery has a constant 12.75 volts. I called the dealership where I purchased the vehicle. They told me to bring it in this morning so they can take a look at it. They gave me a 1000mile/1month warranty with the purchase of the vehicle and now this happened just a few days that I have passed the one month and passed the 1000miles by 200miles. Isn't that some ****? I really hope that they will honor it and fix this issue. Mind me I havent even made my first payment on the car as it is not due to now coming up on June 8th. Any advice would be greatly appreciated! I love this car it has been an amazing car so far up until this issue. I really hope someone has some answers and can help me out. Another question that I have is if it is the EIS does it need to be done strictly through the Stealership? Reason I ask is I found a few postings on eBay claiming that they fix EIS/ESL issues. I know the keys have to be programmed to the new EIS/ESL and is the reason I ask. This is the posting I saw on eBay and wondering if this would be ok to use https://www.ebay.com/itm/MERCEDES-W2...EAAOSw~y9ZJNnQ

Sorry for such the long post. Thanks to everyone in advance that can shed some light onto this issue that I am experencing. I really hope someone can help me out.

 

what you're describing doesnt sound like either an eis or esl. Take it to someone who can actually diagnose this properly before you waste your money.