Volts When Idling?
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C300 Sport/Palladium Silver on Black/P2
Volts When Idling?
I replaced my battery this week, so I have been playing with the built-in diagnostics menu to watch the volts.
My car (alternator) when idling, seems to max output of 13.5 to 13.6 Volts. This seems low to me. My SLK is at 14.0, and another car I have shows 14.1.
What does your W204 C300/C350 show when idling on diagnostic volts menu?
Thanks.
My car (alternator) when idling, seems to max output of 13.5 to 13.6 Volts. This seems low to me. My SLK is at 14.0, and another car I have shows 14.1.
What does your W204 C300/C350 show when idling on diagnostic volts menu?
Thanks.
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Joined: Oct 2014
Posts: 701
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From: Ontario, Canada
2009 C63 AMG, 2010 C250 4Matic Sport
I replaced my battery this week, so I have been playing with the built-in diagnostics menu to watch the volts.
My car (alternator) when idling, seems to max output of 13.5 to 13.6 Volts. This seems low to me. My SLK is at 14.0, and another car I have shows 14.1.
What does your W204 C300/C350 show when idling on diagnostic volts menu?
Thanks.
My car (alternator) when idling, seems to max output of 13.5 to 13.6 Volts. This seems low to me. My SLK is at 14.0, and another car I have shows 14.1.
What does your W204 C300/C350 show when idling on diagnostic volts menu?
Thanks.
Super Member
Joined: Jan 2009
Posts: 929
Likes: 51
From: Silicon Valley, California
Factory ordered 2012 MB C350 w/Dynamic Handling Package
Seems fine to me. Just the other day mine was reading 13V flat, but it will fluctuate depending on what items you have on like AC. Going by memory alone, the highest I've seen is 14.x like you mentioned.
This is why you want a hardwired radar detector with voltage alarms and is one of the reasons why I no longer support Valentine-1 (until they get that feature). Prior to switching to Escorts/Bells, my battery drained in the middle of the Nevada desert without warning. The alternator was still going strong, however when I tried to start the engine again after stopping to get gas I was stuck and the engine didn't want to crank. I didn't think it was the battery at the time since all the equipment was still running (I had the V1) but in the end it was because my battery drained below the minimum crank voltage.
With one however, you'll be warned ahead of time if the battery voltage drops below 10.5 and goes above 16.5. At 10.5V, it still has enough juice for you to crank the engine 1-2 times (in case you are one of those that likes to listen to the radio with the engine turned off). This is a great tool to warn you of impending battery failure, since over time the idle voltage (before you crank your car) will get lower and lower, and you'll have ample warning when you'll need to charge/change the battery.
This is actually one of the things I look at when I start the car on a daily basis. The nice thing is, even if you ignore the gauge (example my wife), it is so idiot proof in that the audible alarms will trigger if you let it go too low, reminding you to change the battery every time you turn the car on. This is why every car I own will always have a radar detector capable to alarm for low voltage.
This is why you want a hardwired radar detector with voltage alarms and is one of the reasons why I no longer support Valentine-1 (until they get that feature). Prior to switching to Escorts/Bells, my battery drained in the middle of the Nevada desert without warning. The alternator was still going strong, however when I tried to start the engine again after stopping to get gas I was stuck and the engine didn't want to crank. I didn't think it was the battery at the time since all the equipment was still running (I had the V1) but in the end it was because my battery drained below the minimum crank voltage.
With one however, you'll be warned ahead of time if the battery voltage drops below 10.5 and goes above 16.5. At 10.5V, it still has enough juice for you to crank the engine 1-2 times (in case you are one of those that likes to listen to the radio with the engine turned off). This is a great tool to warn you of impending battery failure, since over time the idle voltage (before you crank your car) will get lower and lower, and you'll have ample warning when you'll need to charge/change the battery.
This is actually one of the things I look at when I start the car on a daily basis. The nice thing is, even if you ignore the gauge (example my wife), it is so idiot proof in that the audible alarms will trigger if you let it go too low, reminding you to change the battery every time you turn the car on. This is why every car I own will always have a radar detector capable to alarm for low voltage.
Last edited by edgalang; Oct 23, 2014 at 05:22 PM.
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C220 CDI SLK 200
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2015, ML250 BlueTEC
Voltage---Valentine V 1
Seems fine to me. Just the other day mine was reading 13V flat, but it will fluctuate depending on what items you have on like AC. Going by memory alone, the highest I've seen is 14.x like you mentioned.
This is why you want a hardwired radar detector with voltage alarms and is one of the reasons why I no longer support Valentine-1 (until they get that feature). Prior to switching to Escorts/Bells, my battery drained in the middle of the Nevada desert without warning. The alternator was still going strong, however when I tried to start the engine again after stopping to get gas I was stuck and the engine didn't want to crank. I didn't think it was the battery at the time since all the equipment was still running (I had the V1) but in the end it was because my battery drained below the minimum crank voltage.
With one however, you'll be warned ahead of time if the battery voltage drops below 10.5 and goes above 16.5. At 10.5V, it still has enough juice for you to crank the engine 1-2 times (in case you are one of those that likes to listen to the radio with the engine turned off). This is a great tool to warn you of impending battery failure, since over time the idle voltage (before you crank your car) will get lower and lower, and you'll have ample warning when you'll need to charge/change the battery.
This is actually one of the things I look at when I start the car on a daily basis. The nice thing is, even if you ignore the gauge (example my wife), it is so idiot proof in that the audible alarms will trigger if you let it go too low, reminding you to change the battery every time you turn the car on. This is why every car I own will always have a radar detector capable to alarm for low voltage.
This is why you want a hardwired radar detector with voltage alarms and is one of the reasons why I no longer support Valentine-1 (until they get that feature). Prior to switching to Escorts/Bells, my battery drained in the middle of the Nevada desert without warning. The alternator was still going strong, however when I tried to start the engine again after stopping to get gas I was stuck and the engine didn't want to crank. I didn't think it was the battery at the time since all the equipment was still running (I had the V1) but in the end it was because my battery drained below the minimum crank voltage.
With one however, you'll be warned ahead of time if the battery voltage drops below 10.5 and goes above 16.5. At 10.5V, it still has enough juice for you to crank the engine 1-2 times (in case you are one of those that likes to listen to the radio with the engine turned off). This is a great tool to warn you of impending battery failure, since over time the idle voltage (before you crank your car) will get lower and lower, and you'll have ample warning when you'll need to charge/change the battery.
This is actually one of the things I look at when I start the car on a daily basis. The nice thing is, even if you ignore the gauge (example my wife), it is so idiot proof in that the audible alarms will trigger if you let it go too low, reminding you to change the battery every time you turn the car on. This is why every car I own will always have a radar detector capable to alarm for low voltage.
