W204 Red Battery Light
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Joined: Jul 2022
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2012 Mercedes C250 Base
W204 Red Battery Light
I am the owner of a 2012 C250 Base, I was driving the other day when a red battery light appeared on the dash. I have driven it three times since then- Once to get home, and to/from work the next day. The car read 11.8v while driving on the first two drives, but on the third drive it sat around 13.5v with spikes between 12-14.5. The car has approximately 116k miles with the only major services being the steering lock motor as well as a persistent oil leak. With budget in mind, would I be better off replacing the alternator or only the voltage regulator?
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Joined: Mar 2019
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From: Aurora,CO
06' Audi Quattro, 00'SL500
I am the owner of a 2012 C250 Base, I was driving the other day when a red battery light appeared on the dash. I have driven it three times since then- Once to get home, and to/from work the next day. The car read 11.8v while driving on the first two drives, but on the third drive it sat around 13.5v with spikes between 12-14.5. The car has approximately 116k miles with the only major services being the steering lock motor as well as a persistent oil leak. With budget in mind, would I be better off replacing the alternator or only the voltage regulator?
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
$50 Reg.
I am the owner of a 2012 C250 Base, I was driving the other day when a red battery light appeared on the dash. I have driven it three times since then- Once to get home, and to/from work the next day. The car read 11.8v while driving on the first two drives, but on the third drive it sat around 13.5v with spikes between 12-14.5. The car has approximately 116k miles with the only major services being the steering lock motor as well as a persistent oil leak. With budget in mind, would I be better off replacing the alternator or only the voltage regulator?
When rotor brushes gets worned out the output voltage is all over the place.
It being a Benz there are other reason the voltage could get out of control. It's not uncommon for some cars to deep drain the system battery.
🤞
Thread Starter
Newbie
Joined: Jul 2022
Posts: 5
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2012 Mercedes C250 Base
The genuine voltage regulator is about $50 from FCP...
When rotor brushes gets worned out the output voltage is all over the place.
It being a Benz there are other reason the voltage could get out of control. It's not uncommon for some cars to deep drain the system battery.
🤞
When rotor brushes gets worned out the output voltage is all over the place.
It being a Benz there are other reason the voltage could get out of control. It's not uncommon for some cars to deep drain the system battery.
🤞
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Joined: Jun 2016
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From: Panama City, FL
2020 C300, 2013 C250, 2000 Boxster S
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
You need to either go to a dealer or shop at a site that identifies parts by VIN because there are at least 2 different alternators available for the 2012 C250 and each requires its own regulator.
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From: Panama City, FL
2020 C300, 2013 C250, 2000 Boxster S
Odd Piggy is correct. I jumped the gun. If you send your VIN I can look up the correct voltage regulator part number.
