cars running voltage ?

[BlueCivic83]

ok guys i had some altrnator problems and i was wondering what are your running volatge ?

whats the lowset the car 's voltage can go with all acceories running and amps pounding while idleling ?

[SilverY2KCivic]

Well it depends on the ambient outside temp, and also how long you've been idling for. If your car has been running for a bit, it may not have as much voltage at idle as say when you first fire it up in the morning. I have a volt meter in my '00 Civic coupe, and here's what I've noticed with things. In the wintertime and at night (So. Cali I live in) the car maintains a constant 14 volts (maybe 0.2 or so more depending on conditions). Some mornings the car will fire up reading 15 volts, but this is only on real cold mornings. On hot summer days it'll usually be about 13.5 volts when cruising on the freeway. At idle it'll usually drop to between 12 and 12.5 volts, then jump back up to 14 when the car is moving. Also when at idle the voltage can spike up when the acc. fan turns on.

These readings are taken (the night time ones) with radio and 300w amp running, as well as my headlights, and 55w foglights. Hope this info helps you out some. Also my car still retains the stock Honda 70A OEM alternator unit as well as original batter that came on the car from the factory when I got it new back in Dec of '99. So going 4 years strong on that battery.

[BlueCivic83]

thnaks, mine runs at most of the times 12.80 , higest 13.80 and lowest 11.95 . All this is without my 400watt amp wehich i disconected for another reason but i 'm afraid of reconnecting it.

[i_a_n112784]

A car shouldnt get higher than 14.4v, and not lower than 11v. If the voltage gets higher, electronic devices tend to get destroyed, lower and they tend not to work.

[SilverY2KCivic]

Originally Posted by i_a_n112784

A car shouldnt get higher than 14.4v, and not lower than 11v. If the voltage gets higher, electronic devices tend to get destroyed, lower and they tend not to work.

This maybe true, but that's how the law of elctricty works in climate conditions. More power flow (less charge loss) at colder temps, and much higher voltage loss at hotter temps. Once the car gets warmed up my voltage drops to about 14.5v It's only on real cold mornings that it'll start up at 15, not often though so I'm not worried. If it's gonna destry anything, it would have already.

As for your amp Blue Civic, I wouldn't worry too much unless you have the volume cranked up high. My 300w amp powers at "10 (1000w sub) and it doesn't draw much power at all from what my volt meter tells me. In fact, the rear window defroster seems to pull more current than even my 55w fogs do. You should be fine with your amp, hook it back up and just monitor it taking periodic voltage readings to see where it's at.

[BlueCivic83]

thanks, hooked it up last night and everything is just fine but my voltage does go down to 11.88 at times but not for long.

[ra11585643]

remember that a volt meter in a car is only a realitive reading, accurate enough for a glance but not good for a true reading. If your alternator is functioning properly and the voltage regulator is working right it should not charge above 14.5 at any time or it will damage the battery. voltage will vary with load and temp but should not drop below 12.6