First, it's not uncommon for the gauge to drop below 13 or go well above 14. The charging system is supposedly "smart". Seeing swings in the gauge is not unusual.

In your case I think there really is an issue if you are getting the "Check Battery" light.

The symptoms do sound like either a failing tensioner or oil/coolant is getting on the belt causing it to slip.

New alternators are known to prematurely fail but that wouldn't account for the rise in temperature.

 

Thank you for the advice. I’ll start with the tensioner and hopefully that helps.

First, it's not uncommon for the gauge to drop below 13 or go well above 14. The charging system is supposedly "smart". Seeing swings in the gauge is not unusual.

In your case I think there really is an issue if you are getting the "Check Battery" light.

The symptoms do sound like either a failing tensioner or oil/coolant is getting on the belt causing it to slip.

New alternators are known to prematurely fail but that wouldn't account for the rise in temperature.

 

It could be a loose or corroded ground connection on a 2013 also. That might give some poor voltage conditions.

 

Tensioner id look at. Since you say voltage drop and temp rise at the same time... leading me to believe a slipping belt.
When it happens do you feel steering get stiff? How about AC if on?

 

Yes, the power steering stops working. I haven’t noticed the AC stop because I haven’t been using it when all of this happens. Going to be replacing the tensioner tomorrow. Hopefully this solves the issues.

 

Be sure to come back and let us know.

 

I side with there seems to be a problem with the tensioner take a good look at the belt for slippage, also release the tensioner pressure from the belt to see how easy, or how far it moves. The belt usually runs from the crankshaft to the alternator, and then power steering pump with the water pump pulls too... loosen the tension, test those components to see if they turn. Ps. Don't forget air compressors for air conditioning can fail too.

 

@Kayla2421 : You've got a 10-11 year-old vehicle. I'd bet you still have the original Drive Belt on there. And it might look new on the outside, but it's underneath ... where the ribs are ... that you need to look closely. I'd pull it off and flex it on the rib side to see if tiny cracks appear. That would be enough to cause it to slip.

I've personally never replaced a Tensioner in my life. And I always drive all my cars past 222,222 miles! Tensioners seem to be pretty stout. In fact, it's usually the Idler pulley that fails ... the bearing eventually gives out.

 

Thank you for the advice. We’re currently working on it now and once I read your comment, I looked at the old belt and sure enough, there’s cracks all throughout it. We’re putting it all back together now with the original tensioner because we can’t get to it to get it off. We will put the new belt back on and see if that helps the issue. If not, we’ve gotta take it to a shop to have the tensioner done it seems.
I’ll update the thread once I’ve driven it enough to know if it’s fixed or not with just replacing the belt.

@Kayla2421 : You've got a 10-11 year-old vehicle. I'd bet you still have the original Drive Belt on there. And it might look new on the outside, but it's underneath ... where the ribs are ... that you need to look closely. I'd pull it off and flex it on the rib side to see if tiny cracks appear. That would be enough to cause it to slip.

I've personally never replaced a Tensioner in my life. And I always drive all my cars past 222,222 miles! Tensioners seem to be pretty stout. In fact, it's usually the Idler pulley that fails ... the bearing eventually gives out.

 

Here's a link to a YT video on replacing the tensioner. Doesn't look like a bad job.....if you have the right tools.

 

Quick update - the original belt was garbage. I’ll attach a picture for reference. There were cracks all throughout it and the ribs themselves looked very worn down compared to the new one. We were not able to get the tensioner replaced, only the belt. Got it all back together and took it on a 20 mile drive and let it idle for a good 20 minutes.
There was no jump in the temp gauge like before when idling. The volt gauge did jump around a bit but not as much as before the new belt. It never went below 13v. Going to keep driving it for now to see if any of the previous issues return, in which we will replace the tensioner.

 

Quick update - the original belt was garbage. I’ll attach a picture for reference. There were cracks all throughout it and the ribs themselves looked very worn down compared to the new one. We were not able to get the tensioner replaced, only the belt. Got it all back together and took it on a 20 mile drive and let it idle for a good 20 minutes.
There was no jump in the temp gauge like before when idling. The volt gauge did jump around a bit but not as much as before the new belt. It never went below 13v. Going to keep driving it for now to see if any of the previous issues return, in which we will replace the tensioner.

Excellent! The only reason to replace the tensioner is if the bearings in it go bad. Belts are maintenance items!

 

I think i replaced my 1st belt at 5 yrs.
Kept the used one as a spare on road trips.
You know youre on long stretches of desert highway..... whats that? A snake?
Nope, someones snapped belt.
Guess they were stuck out there for a while

 

FYI - Got a '13. Double check the the alternator control harness plug at the alternator when you get the chance. Awhile ago found mine had a snapped wire right at the connector. Not sure how or why other than maybe odd flexing. Ended up buying and splicing in a new harness connector pigtail.

 

Any odd sounds when this happens? Possible newer alternator is fine from an electrical standpoint but a bad bearing after running and heating up could be causing an issue at the alternator pulley. This would be similar to the old style compressors going bad and they'd tighten up and it would keep the belt from running freely.

 

While it sounds like you do have some kind of problem, I have always taken a grease gun and squirted some on my finger and lightly put it on both sides of the belt, because they get old and crack. Have done the same thing on my lawnmowers and never lost a belt. The smart charging can be challenging, and confused me for a while, especially when trying to charge the battery. Once I understood what was going on (and it has a fail safe mode so as to not run your battery down), I just let it be and have zero problems. Even put the battery I thought I needed in my wife's car. Obviously something is wrong, so sounds like either the tensioner or A/C compressor. On GM cars, even in winter, the A/C comes on when you use defrost.