Question about battery voltage

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boostedtsiawd

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When i have my car running in park im getting 13.56-13.57 volts on my multimeter but then when i turn on my 6000k hid headlights it drops to 13.13-13.15 so does this mean my alternator is on its way or is my battery not strong enough? Also when i turn my lights on the rpms go up just a lil bit.

My battery has 550cca and its a 88 nissan 200sx 3.0 v6.
 
Turn on all loads. Blower motor, rear defrost, wipers, radio all at idle & check the voltage. If it's below 12.9, you have an alternator or voltage drop issue
 
You're at idle and you're reading too much into the results. From what you've said, it sounds normal. If you're worried about the battery, take it to an auto parts store and have it load tested. The voltage dropping at idle when an additional load is added is normal. Your battery isn't dying. Nothing to really worry about here unless you have other symptoms.
 
Originally Posted By: asand1
Should be at 14V.


There is no one size fits all proper voltage for every application, some systems operate at 13.6v while temperature compensated systems can see as high as 15v under normal operation.
 
Originally Posted By: Wolf359
You're at idle and you're reading too much into the results. From what you've said, it sounds normal. If you're worried about the battery, take it to an auto parts store and have it load tested. The voltage dropping at idle when an additional load is added is normal. Your battery isn't dying. Nothing to really worry about here unless you have other symptoms.


I'd agree with this. Buzz the engine up a little and if the voltage comes up, you're good-to-go. Remember, most of the time the engine is running at 2k to 3k RPM.
 
People are all posting correct info, and I'd like to add:

If everything is working properly, but the battery is on it's way out, the Alternator will struggle more.

If the battery is weak it becomes part of the electrical load.

My Honda Fit had the OEM battery in it at 5 years and was starting to get a bit weak, so I experienced on and off headlight dimming.

I put in a new battery, a CarQuest Deka (East Penn) and the issue disappeared.

Have the battery load tested, that is the simplest place to start.

Or at least check it in the morning and see if it is at least over 12.6V. If it is, turn on your headlights for 6-7 seconds with the car off, and re-check the Voltage at the posts.

If it is still close to 12.6V it is probably ok the battery, but if it falls to like 12.2-12.3V get a load test for sure.
 
Originally Posted By: boostedtsiawd
When i have my car running in park im getting 13.56-13.57 volts on my multimeter but then when i turn on my 6000k hid headlights it drops to 13.13-13.15 so does this mean my alternator is on its way or is my battery not strong enough? Also when i turn my lights on the rpms go up just a lil bit.

My battery has 550cca and its a 88 nissan 200sx 3.0 v6.


Is this a quality multimeter or the free one from HF?
 
The voltage observed with the lights on is pretty low. I agree to get RPMs up and see. Also go on Amazon and get a little cigarette lighter volt meter so you can keep tabs while driving. Less than $10, and some brands offer led colors to match the car.

13.1 won't really charge the battery, but it may not deplete either. That's a big question though.
 
No mention of where on the vehicle the voltage readings were taken, no mention of state of battery charge when readings were taken... so no real conclusions can be made.
 
Originally Posted By: boostedtsiawd
When i have my car running in park im getting 13.56-13.57 volts on my multimeter but then when i turn on my 6000k hid headlights it drops to 13.13-13.15 so does this mean my alternator is on its way or is my battery not strong enough? Also when i turn my lights on the rpms go up just a lil bit.

My battery has 550cca and its a 88 nissan 200sx 3.0 v6.
Having the caps lock on wears out the battery.
 
On my Accent the battery voltage while running whether small or big electrical load is down to 13.6 or so. I suspect the alternator as it has 114k miles on it.
 
Get one of these:
http://www.amazon.com/Equus-3721-Battery-Charging-Monitor/dp/B000EVWDU0


INNOVA 3721 Battery and Charging System Monitor
by Innova 846 customer reviews 40 answered questions

4105fQmT1vL._SY450_.jpg
 
Originally Posted By: HangFire
No mention of where on the vehicle the voltage readings were taken, no mention of state of battery charge when readings were taken... so no real conclusions can be made.


Exactly.

Measuring at the alternator output post, across battery, or at headlights?

Most of my auto's run 13.8V on idle and 14.25V at higher rpm measured across the battery with headlights on low beam.
 
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