voltage while car is running? - Honda-Tech

Go Back   >
Log In 


voltage while car is running?

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 05-21-2009, 01:17 AM   #1
Honda-Tech Member
Thread Starter
 
GsDAteg's Avatar
 
Join Date: Feb 2006
Location: Nevada
Posts: 480
Default voltage while car is running?

I was wondering how many volts there should be when a alternator is charging properly? My battery light and ABS light are going off on on but everything else seems to be normal. Car is a 90' Integra if it matters.
GsDAteg is offline   Reply With Quote
Old 05-21-2009, 05:20 AM   #2
Honda-Tech Member
 
ken9's Avatar
 
Join Date: Nov 2008
Location: Ontario, Kanada
Posts: 1,806
Default Re: voltage while car is running?

It should be around 14.7 volt on alternator.
ken9 is offline   Reply With Quote
Old 05-21-2009, 05:36 AM   #3
Honda-Tech Member
 
imadigitalgod's Avatar
 
Join Date: Sep 2004
Location: olathe, ks
Posts: 892
Default Re: voltage while car is running?

Quote:
Originally Posted by ken9 View Post
It should be around 14.7 volt on alternator.
Id say 13.5v - 14.5v, most likely in the high 13's tho
imadigitalgod is offline   Reply With Quote
Old 05-21-2009, 05:37 AM   #4
fcm
Old Fart
 
fcm's Avatar
 
Join Date: May 2004
Location: kelowna, bc, canada
Posts: 25,418
Default Re: voltage while car is running?

At batt. the voltage should be 12.5 when not running and at least 13.5 when running at idle. 94
fcm is offline   Reply With Quote
Old 05-21-2009, 07:33 PM   #5
Honda-Tech Member
 
twentyhurtz's Avatar
 
Join Date: Mar 2006
Location: Hattiesburg, MS
Posts: 1,430
Default Re: voltage while car is running?

yep, float without car on 12v plus or minus half a volt, idle - car warm... 13.8ish, full limitation of voltage regulator- 2k rpms or so... 14.5v ish..
twentyhurtz is offline   Reply With Quote
Old 05-21-2009, 07:34 PM   #6
Honda-Tech Member
 
twentyhurtz's Avatar
 
Join Date: Mar 2006
Location: Hattiesburg, MS
Posts: 1,430
Default Re: voltage while car is running?

but don't tell my local advanced autoparts i said that, they will get pissed, cause according to them the alternator i bought from them, which DOESNT WORK, should idle at 14.5v all THE TIME! - advanced autoparts... idiots..
twentyhurtz is offline   Reply With Quote
Old 05-21-2009, 11:58 PM   #7
New User
 
Join Date: May 2009
Posts: 2
Default Re: voltage while car is running?

I think a fully-charged car battery, in good condition, with no load on it, will measure about 13.2 volts. With the engine running, if the alternator and voltage regulator are working correctly, you should measure about 14 to 15 volts at the battery.
willforest is offline   Reply With Quote
Old 05-22-2009, 12:05 AM   #8
Honda-Tech Member
Thread Starter
 
GsDAteg's Avatar
 
Join Date: Feb 2006
Location: Nevada
Posts: 480
Default Re: voltage while car is running?

So what voltage makes your charging light and ABS lights go off then? Mine reads about 14.6 when cold and between 13.3 and 13.4 when warm. Sounds pretty on to me from what you guys are saying. I mean my idle voltage when warm might be a little low but as soon as I turn my car on when cold the battery/ABS lights go on, even though at cold idle it was reading 14.4v.

I was thinking I needed to replace my alt. but are there other reasons for this? I mean if I'm getting a reading of over 14v when I first start up, why is my battery light coming on?
GsDAteg is offline   Reply With Quote
Old 05-22-2009, 08:34 AM   #9
Honda-Tech Member
 
ken9's Avatar
 
Join Date: Nov 2008
Location: Ontario, Kanada
Posts: 1,806
Default Re: voltage while car is running?

Could be your battery having some issues.
ken9 is offline   Reply With Quote
Old 05-22-2009, 09:07 AM   #10
Honda-Tech Member
 
twentyhurtz's Avatar
 
Join Date: Mar 2006
Location: Hattiesburg, MS
Posts: 1,430
Default Re: voltage while car is running?

usually on most dc devices there is a solid state limit switch, i know here at work i deal with many devices that i have to put on a test bench to find the preset voltage point to where something trips into protect mode or shuts off, usually on dc devices that setting is at 10.99 volts or 11.49 volts, i guess it all depends on the unit, some even as low as 10.49 volts.
twentyhurtz is offline   Reply With Quote
Old 05-25-2009, 08:37 PM   #11
New User
 
Join Date: May 2009
Posts: 2
Default Re: voltage while car is running?

The alternator's voltage output depends on air temperature. When it's really cold the battery becomes more resistive and requires a higher voltage to get charged. The regulator typically puts out a slightly higher voltage then. If it's hot then the voltage out of the regulator may be less, maybe in the 13's.

Something like 14.3V sounds normal, but part to part or car to car, typical difference 0.3V in comparison is possible. The real goal is to ensure the regulator is working, it means putting out a voltage higher than 13V and lower that high 14's. If the regulator puts out 15V or more then it can overcharge the battery.

Last edited by willforest; 05-25-2009 at 08:45 PM.
willforest is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
2005 accord ex coupe tcs light and triangle on Jj Jj Introduce Yourself 0 06-07-2016 09:26 PM
95 Accord wiring issue? running lights Sarah Royal Honda Accord (1990 - 2002) 0 01-17-2016 06:13 AM
Brake light wont shut off BigAnteg Honda Civic / Del Sol (1992 - 2000) 19 05-21-2009 05:44 AM
check engine light turns on randomly and then when i restart the car it goes away? ramz7887 Tech / Misc 6 11-13-2007 03:07 PM
Dash lights and tail lights out on '97 accord distra Honda Accord (1990 - 2002) 7 11-12-2007 03:39 PM


Tags
accord, alternator, battery, bench, car, civic, del, float, honda, idle, regulator, running, sol, test, volt, voltage, volts

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 07:27 AM.



Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.