2020 E450 Convertible Alarm Gremlin
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2020 E450 Cabriolet
2020 E450 Convertible Alarm Gremlin
My W213 convertible shows 13,375 miles on the odometer and looks and runs like a brand new car, just like a 13,000 mile car should. About 3 weeks ago, the alarm went off at 2 am. I turned it off, checked the car, nothing. Since then, the alarm has continued to go off every couple of days at random times of the day, only twice at night and always in my house, never anywhere else. Last week I took the car to the dealership (I have an extended warranty), they kept it from Tuesday until Thursday, ran every diagnostic in the book and found absolutely nothing. Batteries are good, FOB batteries are new, charging system is perfect, all sensors work, no fault codes, etc. The service advisor called me today and said that the shop foreman, who was off last week, would like to check one more thing and gave me an appointment for the day after tomorrow, Thursday, August 28. Does anybody have any ideas?
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My W213 convertible shows 13,375 miles on the odometer and looks and runs like a brand new car, just like a 13,000 mile car should. About 3 weeks ago, the alarm went off at 2 am. I turned it off, checked the car, nothing. Since then, the alarm has continued to go off every couple of days at random times of the day, only twice at night and always in my house, never anywhere else. Last week I took the car to the dealership (I have an extended warranty), they kept it from Tuesday until Thursday, ran every diagnostic in the book and found absolutely nothing. Batteries are good, FOB batteries are new, charging system is perfect, all sensors work, no fault codes, etc. The service advisor called me today and said that the shop foreman, who was off last week, would like to check one more thing and gave me an appointment for the day after tomorrow, Thursday, August 28. Does anybody have any ideas?
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2020 E450 Cabriolet
Thank you for your comments
It only happened twice at night but always in my house. No, the 2 key fobs can't be pressed inadvertently where they are kept. One of the instances when the alarm went off I was walking by the car about 7 to 10 feet from it. There was nothing around, not even a light breeze.
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It only happened twice at night but always in my house. No, the 2 key fobs can't be pressed inadvertently where they are kept. One of the instances when the alarm went off I was walking by the car about 7 to 10 feet from it. There was nothing around, not even a light breeze.
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2020 E450 Cabriolet
When I said it's only happened twice at night, I didn't mean the same night. I meant to say that since the issue began it has only happened at night in 2 occasions, the rest has been during the day. Having said that, last night it happened again, so now it's thrice at night.
MBWorld God!
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When I said it's only happened twice at night, I didn't mean the same night. I meant to say that since the issue began it has only happened at night in 2 occasions, the rest has been during the day. Having said that, last night it happened again, so now it's thrice at night.
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2020 E450 Cabriolet
Nothing that wasn't there during the 7 previous months. Besides, I was 10 feet from the car for one of the events. There was nothing. We live on a 1 way street across from a passive park.
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MB is very sensitive to electrical voltage swings, so my question is, is the vehicle 12V battery sufficiently charged to avoid maybe causing a glitch in the system?
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2020 E450 Cabriolet
According to Mercedes Benz of Cutler Bay and to a Mercedes-only independent mechanic, yes, the battery and the charging system are in perfect state and working per specs.
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I guess I will just go with the not all dealerships are created equal and suggest trying a different MB dealership to see if they can find the issue.
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I took the car back on Thursday, August 28. They called on Wednesday, September 3, and told me that they'd dug deep and found that a module in the console showed that the alarm had gone off because the console's clamshell doors were opened, which obviously wasn't true. They checked the clamshell doors "switches" or contacts or whatever, found that one was sending the false reading, replaced it and they held the car until the end of the day on Thursday to make sure the false reading didn't come back. I picked up the car and, so far, it's been fine. However, since they had the car there, I also asked them to replace the battery, which seemed to be fine but my car is a 2020 model year and it had the original factory battery, so who knows.
MBWorld God!
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I took the car back on Thursday, August 28. They called on Wednesday, September 3, and told me that they'd dug deep and found that a module in the console showed that the alarm had gone off because the console's clamshell doors were opened, which obviously wasn't true. They checked the clamshell doors "switches" or contacts or whatever, found that one was sending the false reading, replaced it and they held the car until the end of the day on Thursday to make sure the false reading didn't come back. I picked up the car and, so far, it's been fine. However, since they had the car there, I also asked them to replace the battery, which seemed to be fine but my car is a 2020 model year and it had the original factory battery, so who knows.
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