C32 AMG, C55 AMG (W203) 2001 - 2007

Voltage

Old Aug 1, 2016 | 09:16 AM
  #1  
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C32 amg
Voltage

Just curious about everyones battery voltage, I had battery alternator light come on one day. Mine is at 13.7, under load it went down to 12.2
I think alternator voltage regulator on its way out
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Old Aug 1, 2016 | 11:11 AM
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Load test was just done by putting AC on and the fan on high, but that's when the voltage dropped to the 11s.
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Old Aug 1, 2016 | 12:22 PM
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Originally Posted by Morphh
Load test was just done by putting AC on and the fan on high, but that's when the voltage dropped to the 11s.
11s is not good. My dashcam is set to shut down at 11.5. in general, MB cars are very sensitive to voltage and other than cranking, the voltage should be in the 13s.
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Old Aug 1, 2016 | 12:31 PM
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I have found the the fan mod I have draws .7 volts, I have been running like this for 2 years w fan mod, I cleaned my ground connections and added a few more grounds. I think voltage regulator is going. So that message battery/alternator low on dash has come on 2twice in last 2 weeks. While my fan is on.
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Old Aug 1, 2016 | 12:34 PM
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Lenin u able to take measurements of the code3 reservoir ?
Might make one up
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Old Aug 1, 2016 | 01:27 PM
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Originally Posted by Morphh
Lenin u able to take measurements of the code3 reservoir ?
Might make one up
That may put me in legal jeopardy in case Brendan decides to start manufacturing them again.
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Old Aug 1, 2016 | 03:20 PM
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Originally Posted by Morphh
Just curious about everyones battery voltage, I had battery alternator light come on one day. Mine is at 13.7, under load it went down to 12.2
I think alternator voltage regulator on its way out


https://mbworld.org/forums/c32-amg-c...-problems.html

Morphh - i just recently went through this too with my Valeo alternator which died at 116k miles. i had a local pepboys install a garbage Reman Bosch unit that couldnt hold 12.5 - 13.0 V while driving despite being new which i had heard was the case but i was in a jam and had them put that unit in.

i found out you can replace the voltage regulator on the Valeo alternator and its pretty cheap and easy (assuming you have the alternator already out) to do with just a few screws. The link above shows pics of the new valeo VR compared to the old VR that i replaced.

i had my indy shop put the old Valeo back in with the the new Voltage regulator and its been working great. starts out at 14.2 and then with AC on and lights it stays around 13.5-13.8 while driving around. if im stuck in traffic with the AC on it does drop to 13.3 - 13.5 which I'm not worried about.... that reman Bosch unit would drop to 11.5-12V in traffic and was terrible...
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Old Aug 1, 2016 | 05:22 PM
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I think I figured it out when the fan on (mod) I had it power by 5amp fuse, switched it to 10amp fuse, seems little better, staying around 13.6 - 13.3, still think voltage regulator on its way out, car has 112,347 kilometres
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Old Aug 3, 2016 | 10:25 PM
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Morphh - keep an eye on the voltage. when the alternator dieds it goes quick with some warning but not much.

when mine died, i got one initial warning while driving "battery/alternator visit workshop" and the volts was below 12 and it stayed there for a day of driving.

but the 2nd time it came up the next day i had about 10 minutes driving in the car car and the volts died to below 10 and immediately the alternator was dead while i was out on the road and had to get it towed to the shop...

if your volts is staying at 13 or even 12 you probably have some time, but should get it checked out.. if its at 11 when driving then for sure get the alternator checked as if its like my situation its near dead and can go anytime leaving you finding a tow.


cheers
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Old Aug 4, 2016 | 08:31 AM
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I'm keeping eye on it, it only drops when fan mod runs, going to put relay and bigger toggle switch.
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