Light sensor warning and the battery alternator check turns on when accelerating

2005 MERCEDES BENZ C220
317,000 MILES • 2.2L • 4 CYL • 2WD • AUTOMATIC
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DIONIS
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  • 1 POST
Hi, whenever i go full throttle i get the light sensor warning and the battery alternator check. When I get the first warning it just turns off my radio then it comes back again, but when i get the battery alternator warning i can't shift, use turn signals, windows or anything. when i measured the electricity, it came back 20V. what do i do? all those started when my right rear-view mirror got hit and broke the signal light there.
Mar 27, 2022 at 7:10 AM
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JACOBANDNICKOLAS
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Hi,

Where are you getting a 20v reading? That is a serious overcharging issue and likely the result of a voltage regulator issue.

Do me a favor. Follow the directions in this link and let me know the results. Also, if you are certain, it is producing 20v, I would recommend waiting until it is fixed before using it. That much voltage can damage other components.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I'm not sure where you are located, but this model (C220) isn't listed in my manual, so it is likely not offered in the US. My manual starts with a C230.

Let me know the results of the test.

Take care,

Joe
Mar 27, 2022 at 7:34 PM