Flickering dash at idle, did not start after I shut it off, battery voltage 12.7 when off. Is alternator fine?

[apollo18]

hey all, i have a 15 rav 4 with 107k miles on it. i am not sure how old the battery is but the previous owner told me it was replaced recently but not sure if that is true. secondly, the alternator i assume is oem since it says toyota denso and i dont recall past owner saying if he replaced it.
just to add more to the info, last night it was raining super bad but when i drove the car home it acted normal and had no issues. parked it outside for the night (it rained heavy all night). got in, today in the morning and started up fine and didnt notice any issue. drove about 20 mins on city/highway and it acted completely normal. parked it and then fired it up as i left work, and it started normal and gave no odds sign. the drive today was prob about 20 miles to home on the highway/city with tons of traffic.

Right when i get home, as i went to reverse to adjust my park i felt a wierd feeling in the steering and thought maybe i turned it the wrong way. I looked at the dash and noticed the light was kinda flickering where the odometer is. thought welll, thats odd. so i backed up and parked the car and sat at idle for a few. i revv'd in neutral to see if the flicker would go away but it stayed the same. as the engine was on, i opened hood and checked to see if the belt was messed up but looked all normal. thought maybe it was an issue i could get to look at tomorrow or later .' so i shut the car off and got my stuff out

however as i went to lock the car, i noticed it didnt lock. so im like **** maybe batt dead or contacts are bad ? so i hopped in again, and tried to fire it up and nothing really turned on, no ding ding, just a dim little intermittent light in the dash.

got some noco cleaner and protectant and some wire brushes. sprayed the clear waited some time, scrubbed, rinsed it off, unscrewed both terminals and cleaned some more with brush and cleaner. rinsed.
re installed terminals and went inside and put the key in and had light, however went to turn it over and it started but immediately shut off

*in my head im like oh no maybe alt is bad but lets give it a few seconds to maybe reengergize or something *

turned the key and voila! it started, dash was bright and did not look dim and flickery.

went outside to the battery and started using the multimeter in diff places. was getting 14.23v on both posts, and on various different portions of the cable and post. i mixed it up and was constantly getting 14.23 ish. the cable is kinda covered up with plastic and other things so its hard to know exactly if i am touching the vehicles cable terminals but i played around and moved around alot

hopped in and took it for a short drive with ac full blast and headlights on and came back. this time parked, kept it running, max ac with headlights on.
mulitemeter to different parts of battery posts/terminal/ground cable area was getting 13.99v everywhere. i went inside and turned headlights off, and tested again. started getting around 14.1v ish, then i went inside and turned ac off. and then was back to 14.2 ish v

finally shut the hood and called it quits for for a few hours.
just now i started it again and hooked up the multimeter and got 14.8v at all the spots, then waited 1-2 mins and it lowered down to 14.1 ish v. took it for a 15 min drive and it felt fine. is 14.8v also fine at start up?

now the question is, are these numbers okay? on the drive and at idle it gave no symptoms of low volt or anything, no dimm, no flickering. i assume it didn't stay on the first time as maybe ecu was confused or maybe some other random issue. if all fixed i guess dirty terminals was the issue

so i hope its get but would love some input

 

[zrxkawboy]

Sounds to me like your charging system is working. I would swing by one of the parts stores...they will test your battery and charging system for free.

 

[apollo18]

Sounds to me like your charging system is working. I would swing by one of the parts stores...they will test your battery and charging system for free.

ty so much ill do that tomorrow but do u ever feel they prematurely just say a battery is bad if the cca is a tad low? like i could care less about cca, i just want a working batt but i will take there word if the alternator is said to be bad
ofc when cca is super low its an issue and ill replace

 

[zrxkawboy]

Usually you can stand right there and watch them do the test.

 

[billt460]

I purchased a Foxwell battery / charging system tester on Amazon. It's inexpensive, easy to use, and works well. It will easily tell you the condition of your battery, as well as the condition of your charging system.

You will always have it on hand when things like this happen. It beats the hell out of guesswork. It also has provisions for testing the battery both in and out of the vehicle.

https://www.amazon.com/dp/B01ANF1D7U?ref=nb_sb_ss_w_as-reorder_k0_1_22&amp=&crid=4O2TZVSAYSVH&amp=&sprefix=foxwell+battery+tester

 

[hemitom]

Sounds like you had a bad connection at the battery ?

 

[RooflessVW]

Bad battery. Voltage normal but fails under load.

 

[nwjones18]

I purchased a Foxwell battery / charging system tester on Amazon. It's inexpensive, easy to use, and works well. It will easily tell you the condition of your battery, as well as the condition of your charging system.

You will always have it on hand when things like this happen. It beats the hell out of guesswork. It also has provisions for testing the battery both in and out of the vehicle.

https://www.amazon.com/dp/B01ANF1D7U?ref=nb_sb_ss_w_as-reorder_k0_1_22&amp=&crid=4O2TZVSAYSVH&amp=&sprefix=foxwell+battery+tester

I don't know why everyone doesn't at least have one of these..

https://www.amazon.com/Neiko-40510A-Volt-Battery-Tester/dp/B07B3R4TS6/ref=sr_1_9?crid=20JUT5NA5O3MV&keywords=battery%2Btester&qid=1700226235&s=automotive&sprefix=battery%2Btester%2Cautomotive%2C171&sr=1-9&th=1

 

[apollo18]

Sounds like you had a bad connection at the battery ?

I think so but not sure hoping for some input from others ahaha. I’m positive it is but not sure how to rule out bad battery

 

[apollo18]

Update! Just wanted to add that when I first hooked up my multimeter yesterday after about an hour of the vehcile being off (when it first had the issue)

I was getting 12.7v at the battery which made me think contacts are dirty and resulted in me cleaning it

Further more last night before starting it was at 12.6v ish I can’t remember exact and then I took it for a 15 min drive and brought it back home and went to bed for the night. Today I woke up at the battery off is at 12.49v at diff places. I doubt I have that much paristitic draw. Ifs just a stock Rav 4

Is this symptoms that the battery isn’t taking a charge? Imma head to auto store soon and see what they say. The odd part is I see a sticker on it that says 06/22 which must be the “recharge by date” so I assume the old owner did replace it about a year ago. Can I new battery die this quick? I am in the hot south but if it’s the battery that’s super early no?

Thx

 

[wag123]

Update! Just wanted to add that when I first hooked up my multimeter yesterday after about an hour of the vehcile being off (when it first had the issue)

I was getting 12.7v at the battery which made me think contacts are dirty and resulted in me cleaning it

Further more last night before starting it was at 12.6v ish I can’t remember exact and then I took it for a 15 min drive and brought it back home and went to bed for the night. Today I woke up at the battery off is at 12.49v at diff places. I doubt I have that much paristitic draw. Ifs just a stock Rav 4

Is this symptoms that the battery isn’t taking a charge? Imma head to auto store soon and see what they say. The odd part is I see a sticker on it that says 06/22 which must be the “recharge by date” so I assume the old owner did replace it about a year ago. Can I new battery die this quick? I am in the hot south but if it’s the battery that’s super early no?

Thx

A battery can go bad at any time, especially in hot climates. Living in Texas, I have seen it myself, many times.
Assuming that all of the external battery connections are clean and the cables are good, it sounds like the battery has an intermittent internal short or intermittent open internal connection. A battery like this can test good one minute and bad the next which can cause a frustrating diagnostic experience.

 

[twX]

urther more last night before starting it was at 12.6v ish I can’t remember exact and then I took it for a 15 min drive and brought it back home and went to bed for the night. Today I woke up at the battery off is at 12.49v at diff places. I doubt I have that much paristitic draw. Ifs just a stock Rav 4

To get a proper voltage reading, a battery needs to have been at rest for a long time, with no recent charging or discharging. On modern cars, even opening the car door to pop the hood or using the keyless entry will put load on the battery for a while and drop the voltage, and it will take a couple of minutes for that load shut off, then several more minutes for the voltage to recover afterwards. I'd pop the hood when parking the car, then check the voltage the next morning. The newer keyless start fobs might even cause some battery loading if the fob is too close to the car.

The voltage will also read high for over an hour after shutting the engine off. You're probably just chasing a phantom problem that doesn't actually exist, due to the difficulty of taking accurate voltage measurements.

If you want to measure parasitic draw, you can disconnect one of the battery cables and connect your multimeter in ammeter mode between the battery and the cable. (Don't forget to turn the meter back into volt mode before checking battery voltage or it will fry your meter). The current should be under 50 mA unless you've recently opened the car door or something.

 

[apollo18]

ty for the help so heres the last update! i took it to autozone but the person couldnt get the proper machine working and the cheapy battery analyzer said battery was a pass, told me to goto other autozone thats brand new. went there but the fella wouldn't do the alternator test with the machine, he was kinda a jerk and insisted it only did the battery test and when he did the battery test he entered cca but did not enter the rc when it asked. so when he got the report it said cca was good but rc was bad, ofc the rc is bad if it was entered as 0.
then i drove to advanced auto and at first the guy tried to tell me the alt was good even when the vehicle was off. i nicely asked him to do the test where it asks for vehicle details, we started it and it told me to rev to 2k ish and i did, and when i came back out he showed me report. starter showed good, alt showed good, and batt said charge and retest. it did not say fail

i assume the connection for my battery and terminals has prob been bad for a little while so imma drive it around for a few days and test again at a store. i can't hookup a battery charger since i am away from now on but i assume the alt and batt are prob fine!

 

[mk378]

The alternator test is little more than measuring the voltage with the engine running and the headlights on-- it should be 13.8 or higher. You can do that yourself.