W204 Red Battery Light
07-09-2022, 01:13 PM
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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?
07-09-2022, 11:41 PM
#2
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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?
07-11-2022, 07:02 PM
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MY'14 W212 M276 3.5NA @55kMi
$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.
🤞
07-12-2022, 02:35 PM
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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.
🤞
07-12-2022, 02:44 PM
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MY'14 W212 M276 3.5NA @55kMi
parts rarity
no worries, dealers have all the best parts for your exact VIN.
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Odd Piggy (07-12-2022)
07-12-2022, 04:34 PM
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07-12-2022, 06:00 PM
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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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alynch (07-12-2022)
07-12-2022, 06:13 PM
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Odd Piggy is correct. I jumped the gun. If you send your VIN I can look up the correct voltage regulator part number.
