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Maybe the autozone guy said too much voltage?

Yes, voltage regulator (VR) is inside the Alt.

Starter should be fine, no worries.

Bad Alts will often damage a battery, so replacing both Alt and Bat is often done.

My guess is your Alt is toast. Having an OEM Alt re-built is often preferred, compared to replacing it with a new/rebuilt one purchased at big name car part stores. Before taking further action I would suggest you make your battery terminal lug connections super clean and happy. Some cables get corroded inside/behind the lug, -not just on the battery. Also follow the black cable down to the car frame (on drivers side wheel well) and disconnect & clean that connection too.
 

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.. do i need to replace the battery as well?? I hope not.
Nobody knows.

I have never owner a battery tester, so all I have ever done is basic voltage tests. I have owned a couple trickle chargers though, very helpful. This however, does not tell you too much. The few times I have had a battery tested, I had car part stores do it.

Want to know more? -here is a link.
http://carbatteryonline.net/car-battery-tester.html

Don't forget about those visual inspections and clean-up of connections comments I made earlier. You need a have some decent mech skills and tools to replace an Alt on the 2.3. Lots of info here about that, so use the SEARCH box to find addl info.

Please watch the first 30 seconds of this video->
https://www.youtube.com/watch?v=F8AGDuhxOKQ&app=desktop
 

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2004 Focus Wagon, Zetec DOHC, Auto
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A bad alternator can take out a battery and vice versa as Marde pointed out.

You can have the battery load tested at the parts store. It should be fully charged before doing the load test to get an accurate test. If the car is not charging the battery then you will need to put a charger on it before taking it up for a load test.

If the battery is running way down or totally dead, don't rely on the alternator to charge it. The alternator can be damaged by doing so.

Having the alternator rebuilt by a local shop if you have one is preferred (better job and lower cost) over rebuilt from parts store.

The 3-wire connector on the alternator should be checked. It is a common failure item.

What is your voltage with car off and car running? If you don't have a voltmeter, use the test mode of the odometer to look at the voltage.
 

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Discussion Starter · #9 ·
The battery reads (with the car off): 12.5 v
The battery reads (with the car on): 14.4 v
The battery reads (with the car on & with AC and load on): 14.0 v

I think -but i'm not sure- the battery seems fine and the issue is with the Alternator or the voltage regulator inside of it.
Any idea??
 

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2004 Focus Wagon, Zetec DOHC, Auto
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Those voltage readings are within the normal range. Offhand it would seem that you don't have an alternator or battery issue. However, intermittent fluctuations or flickering of car voltage is an indication of SOMETHING wrong.

There could be an intermittent short circuit in one of the wires, or a loose connection somewhere as previously mentioned. Also, many times an alternator will appear to be just fine (and test that way too), but develop a problem when it gets hot.

Again, check the 3-wire connection at the alternator along with the other battery cables and grounds. Also put the odometer into the test mode and watch the voltage as you drive the car...see if it is going haywire like jumping to 16V or 10V.
 

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Discussion Starter · #11 ·
Thanks but shouldn't the voltage reading goes down when i put a load on the car?? i thought it should go down to something like 12 or 13 v but even with the load stays up, that's why i though the voltage regulator inside the alternator could be going crazy
 

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2004 Focus Wagon, Zetec DOHC, Auto
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Oh, 16V!!!!! ....BAD. That changes everything.

Problem with alternator or the 3-wire connector to the alternator.

Also have battery tested for possible issues with it....again, charge it fully and then take it to a parts store for load testing.
 

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I'm going to replace the alternator first and see how it goes... since the battery measured 12.5 volt while the car was off
Battery measuring 12.5 V with car off does not mean that it is good...it means that it MAY be good.

I would HIGHLY recommend that you take that battery in and have it load tested while you are buying the new alt.

A defective battery can ruin a new alt just as a new battery can be ruined by a defective alternator.
 

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Discussion Starter · #17 ·
Do you think i should just replace the battery as well?? I went to Autozone twice to test and one said the Alternator is putting out too much voltage and the other one said the battery is bad
 

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2004 Focus Wagon, Zetec DOHC, Auto
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Well, at least the "too much voltage" was correct.

The battery needs to be fully charged to be tested correctly, so maybe it wasn't fully charged.........or maybe it is bad........or maybe they just want to sell you a battery.

All I can do is to recommend that you have the battery load tested after it is fully charged. If you want to go ahead and buy a new battery that is your choice. It certainly won't hurt anything to have a new battery. If it is over 3 years old, then maybe a new battery would not be a bad idea....winter is coming!
 

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Im thinking its something with your - + cable wires....checking the small wires that plug into the alternator as someone else said is a good thing to check out too.....I dont think a low battery will cause your lights to dim and flicker..are you power windows rolling up or down any slower?
 
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