2007 Mercedes Benz S550 W221
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Joined: Oct 2023
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2007 Mercedes-Benz S550 W221
2007 Mercedes Benz S550 W221
hello fellow w221 owners , my mercedes benz s550 w221 wont start . my key fob had went bad and wouldnt turn into the ignition so i replaced my key fob and my car ran excellent until this week . my 2007 s550 163K miles would stall but stay on & ESP & ABS would pop up & every warning on the speedometer, when i would turn it off & start it again everything would be fine but when i went to the store & the car stalled but kept running i cut it off & went inside the store but as i was getting out to go in the store i tried locking the doors with the key fob & none of the buttons worked on the car so i didnt think nothing of it and went shopping but when i came out and tried to start the car my key would not turn into the ignition like my key fob deprogrammed so i called my locksmith who programmed my new key fob and he told me it was still programmed to the car & that it could possibly be a blown fuse or bad sam module . any tips will help because i am not sure why my key wont turn into the ignition please help !
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Joined: Jun 2018
Posts: 146
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From: Stuart, Fl
2008 S550
Well I noticed for some strange reason you have five of the exact same posts but I'll take a stab at this I had almost The Identical problem last year with mine and it was simply a failing consumer battery. This is the large h8 battery in the trunk which Powers the entire vehicle and when it starts to fail crazy things happen like warning lights, system failures...everything goes Haywire. I recommend you remove that back panel and have that battery tested the panel is a little difficult to get out but can be done without removing the fender Wells you just need a plastic wedge with a hook on it that you can get behind it and grab and Pull and wiggle out. I'm 99% this is your problem
