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Discussion Starter · #1 ·
A few weeks ago i posted seeing if everyone had a constant of 13.5 voltage, NOW im reading 13.2 constant with the car on. Is this normal, sometimes its at 13.1 and others 13.7 but for the most time is 13.2
 

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IMO it's perfectly normal. Those fractional voltage variations are trivial and although I am not an expert on electrical equipment, I'm pretty sure that things like ambient temperature, condition of the battery and probably the tolerance of the voltage regulator itself will produce minor fluctuations in the system voltage. I would not be concerned unless it dropped below 13 v or exceeded 14.
 

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Yes, perfectly normal. The charging system should put out between 13 and 14 volts with the vehicle running. It can and will vary due to numerous factors including system load, battery condition, etc... If it goes over 15 volts I would be concerned that the voltage regulator is going south. If it goes too much below 13 volts I would start looking at that as well. All of this is with the engine running.
 

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I concur with the other responses. It sounds normal to me (13.2 - 14.7) depending on load.

DEWFPO
 

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Mines averaged 13.2V. Both with the stock battery and later I changed it to a Die Hard Platinum. Still the same. My stock panasonic battery was/is still fine. just sitting on my floor in the backyard.
 

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Check an electronics chart. The standard 12v battery will bew about 12.7 volts at full charge, With a one amp charge it will be about 13.8V (i.e one volt for th current through the battery. Charge it up to a solid 13.7V, remove the charger ands ad a little loads.. It should drop to 12.7v or threreabouts and hold! Ron

A few weeks ago i posted seeing if everyone had a constant of 13.5 voltage, NOW im reading 13.2 constant with the car on. Is this normal, sometimes its at 13.1 and others 13.7 but for the most time is 13.2
 

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A few weeks ago i posted seeing if everyone had a constant of 13.5 voltage, NOW im reading 13.2 constant with the car on. Is this normal, sometimes its at 13.1 and others 13.7 but for the most time is 13.2
Is there a reason you are monitoring the voltage? Are you having battery or starting problems? If you're having problems, what are the symptoms?
If on the other hand there are no problems and you're just curious, don't worry. The variations in alternator output are perfectly normal.
 

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Mines averaged 13.2V. Both with the stock battery and later I changed it to a Die Hard Platinum. Still the same. My stock panasonic battery was/is still fine. just sitting on my floor in the backyard.
I'm curious. Why did you swap out the stock battery already?

Thanks, DEWFPO
 

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Discussion Starter · #9 ·
I just noticed, before the Fj i had a 2003 Acura Mdx and voltage was always at 14, And noticed how low the Fj was at. NO problems Yet, Just curious to see what you guys normal had it at, i did observe thou, in the mornings the first start of the day, Its around 13.9 for about 30 mins then drops to 13.5 then maintains at 13.3, sometimes even lower as 13.1 Very odd IN my opinion, When most cars are at a steady 14.
 

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I just noticed, before the Fj i had a 2003 Acura Mdx and voltage was always at 14, And noticed how low the Fj was at. NO problems Yet, Just curious to see what you guys normal had it at, i did observe thou, in the mornings the first start of the day, Its around 13.9 for about 30 mins then drops to 13.5 then maintains at 13.3, sometimes even lower as 13.1 Very odd IN my opinion, When most cars are at a steady 14.
I'm pretty sure that the FJ has more electronics, sensors, and wiring then the Acura has. All these extra goodies that came with the FJ, offer more resistance to the electrical system, resulting in a lower voltage reading based on these extra resistances, but as other posters have already mentioned, ~ 13VDC is quite normal for the FJ. :)
 

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I just noticed, before the Fj i had a 2003 Acura Mdx and voltage was always at 14, And noticed how low the Fj was at. NO problems Yet, Just curious to see what you guys normal had it at, i did observe thou, in the mornings the first start of the day, Its around 13.9 for about 30 mins then drops to 13.5 then maintains at 13.3, sometimes even lower as 13.1 Very odd IN my opinion, When most cars are at a steady 14.
Just after you start the FJ the alternator will have more load on it as it works to "top-off" the battery & replenish the power used in cranking the engine. After running, (and charging) for a little while the battery regains its complete charge & the load on the alternator is reduced. At this time the regulator will dial back the alternator's output which, depending on its design, may result in a measurable drop in voltage. This is normal operation & should not be a concern, good luck.
 
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