Can the 12v battery cause weird dash lights?

What year (NVM it's a 2013) and how many miles on the odometer?

How old is your 12v battery?

You can get your codes read at almost all nationwide auto parts stores. Once you get the codes, you can look them up.

It could be the 12v battery, but it could also be more serious, like the brake booster/accumulator.

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Hopefully its less than ten years old and under 150,000 miles. If so the increasingly common $2,500 brake booster failure would be covered.

 

The dash lights generally indicate there are trouble codes you can read from the car. and a few of the different ECUs in the car do have a few trouble codes that are meant to tell you about low voltage issues. So those are completely legitimate examples of how a battery issue can give you dash lights and codes.

Beyond those cases, there are some other issues where very low battery voltage might have led to a malfunction causing a trouble code to be set. If that's what happened, generally you'd expect that the codes you have will include at least one of the "hey, did you see how low this voltage is?" codes as well.

Further beyond that, there's a school of thought where pretty much anything can be pinned on the 12 volt battery with some kind of handwavey explanation, if finding the real explanation just sounds like more work than somebody wants to put in. Enough said about that.

To figure out what's going on with your car, the main thing is to find out what trouble codes it's reporting. Whether those codes are or aren't the ones that might pertain to the battery, then we'll know.

A good scan tool is the easiest way to get the codes, but for some systems in the car it's not the only way. Something very convenient about the brake system is when any of those lights (brake, ABS, VSC, ((!)) come on, you can get the code just by putting a short piece of wire between the Tc and CG terminals of the car's diagnostic port, and counting the blinks of the dash lights. You can search for threads here with more details on that. Then you have the brake system codes, no scan tool needed.

If you see those lights again, that's what I'd recommend doing. You can post the codes here.

 

maybe yes, maybe no

 

I have seen a loose OBD2 reader plug light up the dash and disable regenerative braking among other factors.

 

Shut the car down, remove the OBD2 reader/module from the port, and start the car.