Battery vs Alternator

[Horn_Spanker 524]

Toyota Camry 2.4L.  A couple days ago a new sound started.  Kinda sounds like when your AC compressor kicks in.  But it wasn't the AC.  Since everything is on the passenger side with the serpentine belt, could have been water pump, alternator, AC, power steering?  I was betting on water pump, and was waiting until I saw a leak.  Guess I was wrong?

Today, car wan't start.  Put a charger on the battery for an hour, and it started up.  Volt meter on battery showed 12v at idle and 14v revving the engine. 

Did this Youtube test:  Alternator test  and the sound stopped?

Took the battery to Autozone and it tested bad?

So, is the alternator really bad if it's putting out 14v?

Is it coincidental that the battery went bad a couple days after the noise started?

Could the alternator have harmed the battery?

 

[Horn_Spanker 524]

Also, once started, the car keeps running?

[blacklab 11929]

37 minutes ago, Horn_Spanker said:

Took the battery to Autozone and it tested bad?

Is this a statement or a question?

Yes, if the voltage of the car when running is 14v the alternator is fine and the battery is probably bad.

 

[TwiceHorn 31475]

17 minutes ago, blacklab said:

Is this a statement or a question?

Yes, if the voltage of the car when running is 14v the alternator is fine and the battery is probably bad.

 

Likely true.  But, turn on the electrical stuff in the car and see if the voltage doesn't drop, or better yet put an ammeter on it.

A bad alternator can kill a battery.  It is conceivable that an alternator working hard to charge the battery and supply juice to the vehicle whines like an ac compressor.

Edited May 4, 2023 by TwiceHorn

[Updawg 2266]

How old is the battery? If 3 years that’s the problem

[Horn_Spanker 524]

5 minutes ago, Updawg said:

How old is the battery? If 3 years that’s the problem

About 3.5 years.

How do you explain the new roar of the alternator?

[blacklab 11929]

battery went bad, probably has a cell shorted out, becomes a load on the alternator rather than helping, alternator working extra hard to handle normal loads plus battery

[shnsajax 3591]

I had what I thought was this exact issue last week, but turned out one of the battery terminals was starting to go out. $25 total charge, felt like winning the lottery. 

[Mother mopar 3318]

Static battery should be around 12.5V, running 14.1-14.5V w/an ohm meter. Next, check your alternator w/said ohm meter.
Put red wire lead on the output cable of alt and black on any body bolt (ground) or - side of the battery, it should be 14-14.5v of output.

If you took it and had it load tested at AZ and it was bad then you have your answer. Could be a dead cell as someone else alluded to. Replace the battery and go on w/life.

Not all-encompassing but batteries last maybe 5 years nowadays. I've found Walmart has the best warranty for batteries nationwide.

Regarding squeaking noise, remove the belt and start the car (watch temp gauge) is noise present? No, you know it's rotational based in line w/belt...Idlers, tensions, pulley, etc. Now put the belt back on and start the car, now spray WD-40 on the pulley/idler/tensioners one by one to isolate sound until it stops. When it does, you've isolated said issue and can replace it as needed.

If yes, it's the sound is internal to the engine.

[Jkwellborn 6702]

If he’s asking how to check the battery, you’re gonna get him tangled up in the belt messing with it while it’s running.

[Kennythetiger 9384]

2 hours ago, Jkwellborn said:

If he’s asking how to check the battery, you’re gonna get him tangled up in the belt messing with it while it’s running.

Like our kittens that slept up there when it was cold outside. R.I.P., kitties. 

[Mother mopar 3318]

If he’s asking how to check the battery, you’re gonna get him tangled up in the belt messing with it while it’s running.

I'll admit that but it seems he already knows he has a bad battery as he had it checked (bad load test) and then asked about noise.

From my understanding, he has two issues, one charging, and the other noise...could be related as they're the same system but not related IMO.

[Horn_Spanker 524]

Fuck it!  Are we not 1%s here?  I bought both.

 

[Jkwellborn 6702]

Fuck it!  Are we not 1%s here?  I bought both.
 

It was probably the tensioner.

[RPM 26321]

Quickest way to test a battery is hold a boxwrench against the + and - posts. You'll find out if it's bad.

[blacklab 11929]

You can also test for voltage on 450v breaker bars with a boxwrench.

If it makes a bright blue ball of flame and the wrench disappears into thin air, the bus bars are live.

[fattyflattie 4639]

2 hours ago, Horn_Spanker said:

Fuck it!  Are we not 1%s here?  I bought both.

 

I bought $1000 worth of Odysseas once and went ahead and replaced the alt as well.  It was worth it to not have an old one slowly bleed that high end of a batt, and I was way north of 200k on it anyhow.   Alts are cheap in the grand scheme.   So are tensioners and idlers, if your noise persists.  

[Horn_Spanker 524]

Installed!  Getting a little over 14v on the battery at idle.  Overall, easy except for getting the belt back on.

Gonna give the wife an invoice and see if she pays.......

[horn4life 3760]

Since you are buying the battery. If the battery dies again it's the regulator (often inside the alternator).  What happens sometimes is the regulator does not adjust to the additional load from night driving when you have the lights, wipers, whatever putting on the additional load.  Alternator puts out the 14 amps normally but dips when under load, maybe down to 12 amps which is not enough to fully recharge the battery.  So test the output then turn on the lights, A/C, wipers, and hit the brakes.  The load will always drop for a second but the regulator should adjust the amperage in the alternator back up to the 14+ amps you need to properly charge.

On the squeak, a lot of times the tensioner is the culprit. A quick cheat I have used is to take a spray bottle and spray the tensioner with some water when you can hear the offending squeak.  Oftentimes that little bit of water helps the failing bearings enough to stop the squeak for a few seconds or minutes.  Cheap lazy way to check that particular problem out.  

[Sam Lin 3559]

9 hours ago, Horn_Spanker said:

Fuck it!  Are we not 1%s here?  I bought both.

A real 1%er would have bought a new car.

[Horn_Spanker 524]

Touche

[tx 3 putt 76958]

On 5/3/2023 at 11:11 PM, shnsajax said:

I had what I thought was this exact issue last week, but turned out one of the battery terminals was starting to go out. $25 total charge, felt like winning the lottery. 

Replace the battery = Replace the terminals

 

also double check the blinker fluid