Alternator or Battery?

I was driving home this evening and noticed my voltage guage looked low. I started watching it and the voltage continued to drop. The ABS light and parking light and another lit up on the dash. I started planning my exit off the interstate, then my battery light came on. I got pulled safely over to a gas station and turned it off.

I tried starting it and it was completely dead. I ended up having it towed to my house.

I am thinking the alternator just completely died on me. I am going to test the battery tomorrow for grins. Any advice would be appreciated.

Thanks

 

Sounds like alternator. Voltage dropped below 11 volts as the truck started draining the battery since the alternator wasn’t functioning, hence the lights on the dash getting triggered and the gauge bottoming out.

 

My guess is the alternator will need to be replaced and the battery will be completely dead. When I have had a battery that gets discharged so low it needs a jump I won’t trust the battery. I would have the battery tested if the battery is less than 40% I would replace it

I had my alternator die on once the battery icon on the dash lit up within a couple of minutes all lights on the dash died. I replaced both the alternator and battery

 

Thanks. I will do some digging on it. It will be a few days til I get back to it.

I am blessed to have a work truck to drive home.

 

Its probably just the battery. Replace it and you should be ok. For safety have your alternator checked, but personally, doubt is bad. Mine is original, almost 300k

 

I would note that on Toyota alternators the wearing part, the brushes, are usually accessible and replaceable. About a $20 part. YES. This means you don't have to buy a $300 alternator and give them your old one.

Here is what the brushes (sometimes called just "holder") generally look like: https://www.ebay.com/itm/1659255386...ybQvNsuwLkgXFY_b1xk2e-vjfe3aTXfxoCvYYQAvD_BwE

 

Battery is good. I could smell a burning smell from the alternator. I'm 99% sure it is the alternator. I lucked out and found one on LKQ off of a 2021 with less than 40K miles on it for $120 shipped. As soon as I get it in I will attempt to install it.

 

I recently replaced mine about a month ago. It had finally died after several months of “battery” issues. Bearings were finished. It was a bugger to replace. I also had to replace my rad, so did them at the same time. Having the rad/shroud/fan out of the way made it much easier, but like I said still a bugger of a job. Then it was, since I was in there, replaced the belt, tensioner, and idler pulley. The idler pulley was starting to go, so I would suggest you check those items out “while your in there”. Good luck!

 

Well, I got the LKQ alternator installed... What a job!!! I went ahead and had a shop put new brushes in it for $30. She working again!

After all the trouble getting the old one out, I wanted to make sure the one I bought was good.

 

Nice work! Yeah the alternator is definitely no walk in the park. Good job saving yourself $$ and the satisfaction of doing the job yourself.