How to monitor battery & alternator?
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From: Houston - Clear Lake
C63 coupe, Z3M Roadster garage queen
How to monitor battery & alternator?
I had to put the car on a charger to get it started yesterday - second time in a month. Not sure whether the problem is battery or alternator. Is there a way to monitor voltage and charge amps on FL (2012 ) model?
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12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
The quick test is to measure voltage at the battery not running and then while starting and running. Should be 12.6 fully charged and 13.7-14.5 running.
if it is your original battery then well past it’s lifespan. If voltage isn’t above 13.5 running then may be alternator. Load test will be more definitive and some auto parts stores will do it for free if you bring in the battery.
if it is your original battery then well past it’s lifespan. If voltage isn’t above 13.5 running then may be alternator. Load test will be more definitive and some auto parts stores will do it for free if you bring in the battery.
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From: Boston
2020 E63s Wagon, 2012 C63 AMG Coupe, 1989 560SL, 2023 911 Carrera T
I just had to replace my original battery yesterday. I don't believe there is any way to monitor the voltage from the instrument cluster like you can on newer models sadly.
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MBWorld Fanatic!
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From: Houston - Clear Lake
C63 coupe, Z3M Roadster garage queen
I've not ever messed with the engineering menu. Does tit have anything that would allow real-time monitoring of voltage and charge amps?
Does the Torque app - or other similar apps - offer anything like this?
Does the Torque app - or other similar apps - offer anything like this?
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From: London ON Canada
2012 C300 4Matic Sport Sedan
There is a way to check it just search it up on YouTube. It comes up in the dash, if I was on my computer I'd post the link. I haven't done it in a while and can't remember if the top of my head.
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MBWorld Fanatic!
Joined: Feb 2007
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From: Houston - Clear Lake
C63 coupe, Z3M Roadster garage queen
Found it - thanks Marko.
Here's how to access battery voltage for the FL -
Here's one that DIDN'T work for me. Might be helpful for a PLF, maybe for a non-AMG.
I'm seeing 12.4-12.6 volts on the highway, well under the 14.7-14.8V that I was expecting, so it looks like my 2012 with 40k miles is due for an alternator already. This looks like a PITA job.
The upper line of the display is labeled UB and reads in volts. The lower line of the display is labeled IB, units of measure are A, and values range from maybe -20 to +30 or more. What does IB stand for? Is this amps? Why does it bounce around so much, and what should it look like if the alternator is working properly??
Here's how to access battery voltage for the FL -
Here's one that DIDN'T work for me. Might be helpful for a PLF, maybe for a non-AMG.
I'm seeing 12.4-12.6 volts on the highway, well under the 14.7-14.8V that I was expecting, so it looks like my 2012 with 40k miles is due for an alternator already. This looks like a PITA job.
The upper line of the display is labeled UB and reads in volts. The lower line of the display is labeled IB, units of measure are A, and values range from maybe -20 to +30 or more. What does IB stand for? Is this amps? Why does it bounce around so much, and what should it look like if the alternator is working properly??
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Joined: Jul 2019
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From: New Orleans. LA
amg C63s
Very simple solution. Go to ebay and purchase a small plug in voltage reader that plugs direrctly into your 12v outlet (cigarette lighter style plug) Less than $10. It usually also includes a couple USB ports to charge your phone.
