Few days ago, I noticed that my dash cam would no longer stay on after shutting off the car. The camera has a low power shut off at 12v. Took a multi-meter to the battery, saw that the resting state was at 11.5v. Is this pretty typical with this car?

Details:

• Battery has a 2020 build date.
• No issues whatsoever with any electrical in the car. No symptoms of the starter struggling, fires up each and every time.
• Hooked up the battery tender overnight and pulled the battery off of it about an hour ago. Holding 12.3v after charge.

I'm leaning towards the battery probably needing a replacement, which I intend on doing at the dealer so that my HVAC servos don't take a steaming pile of....

To confirm, is 11.5 low for OEM?

 

A sound 12 volt car battery should have a resting voltage a little over12 volts; 12.3 to 12.6 volts - and with active charging from alternator the battery voltage will typically read about 13.5 to 14.5 volts when the battery is fully, already freshly charged.

My guess is that your battery will likely fail a load test, and probably needs to be replaced.

Batteries can last anywhere from as little as a few years to over 6-7 years. A bad cell will kill a battery quickly and it happens even with brand new batteries. But a high heat climate is typically much worse to reduce the life of a battery than is a cold climate.

You are wise to have it replaced by your local Lexus dealer's service department.

 

Our car's charging systems do not put out as high a voltage as many other vehicles.

Case in point my own car, with fresh brushes in the alternator and a new regulator, puts out 13.5-13.8v while driving with a voltage of 12.4-ish right when the engine is stopped.

My dash cam is set to turn off at about 12.2v, and it quickly gets there.

The battery in mine is actually kinda crap in my opinion... and something with more capacity would be best and could hold a charge longer.

There are other threads though on this. I'd prefer to have a higher capacity battery also.

Behold:

 

Yea, my Lexus battery was also from 2020, and noticed after installing a dash cam with low voltage shutoff (set first to 12.2 then 12.4) that the car struggled to turnover if not driven for more than 3 days.

I replacing it with a Costco interstate, which ended up having more CCA (700 vs 575 OEM). Of course I noticed after buying the Costco battery that I still had a chunk left of the prorated OEM warranty. Oh well.

 

Thank you all! Good info on the active charge, resting state across the board, and also seeing if there is a chunk left of the prorated oem warranty. Going to call the dealer to get a replacement as they've been bugging me every six months for maintenance (I think this is a bit too much).

 

The higher CCA is only a meaningful factor in cold starting conditions measuring 0°F (-18°C) - otherwise the 700 CCA has zero advantage over the OE 575 CCA. If it makes you feel better to have a higher CCA when it's not a factor and has zero effect - then paying more for a higher CCA may provide you with a better state of mind, but nothing more in a real sense. It would be like having two new toothbrushes with toothpaste applied to them ready for use, when you can only use one of them at a time.

 

You're probably right. Now I have to go up north to use all the CCAs

It was more an unexpected surprise (that living in FL, I may never use lol). Both OEM and Costco batteries have 130 RC rating, if it matters. Battery after core and tax was 140 though I had to replace myself. Had I noticed the remaining warranty, I would have likely at least reached out to the dealer to inquire about price. Nothing beats having someone changing it for you.

 

This is a factor that most people are totally unaware of pertaining to car battery CCA ratings and a battery's life.

@EAST - You are in Florida - a mild climate area. You actually should have gone with a lower CCA rated battery. In milder climates a battery with a lower CCA rating will usually last longer than the same battery case size but with a higher CCA rating. The reason is the battery's cell plates. Lead acid batteries have lead cell plates. Batteries with a higher CCA rating must have more lead cell plates, but there is a negative affect to this - that is because the cell plates in a higher CCA battery will necessarily be thinner in order to fit in the same size battery case housing. Furthermore, the most common way for a lead acid battery to fail is for a cell plate to become broken, or one plate corroded into two cell plates. To this extent, the thinner cell plates of a higher CCA battery are much more prone to become corroded in two and/or broken. When you hear that a battery has a bad cell - - this is typically what happened. The service life of a lead acid battery is measured by the thickness of the positive plates. Thicker plates increase the lifespan of battery. This is why a lower CCA battery with its thicker cell plates will typically last longer than a higher CCA battery.

In the case of car starting battery CCA, more is not always better - in fact, less is better in terms of service life!