Weird battery issue at carwash

Took my desperately dirty 2007 through the car wash today. Chose the wash with the undercarriage rinse (don't recall requesting this previously), put the car in neutral to roll through the wash. About 1.5 minutes into the wash - just after the undercarriage spray - the red triangle lit up on the dash and the main battery icon on the display lit up. It told me to put the car in park to charge the battery immediately.

Needless to say I was freaked out at the thought of getting stuck in the car wash and was out of there as soon as I could get free from the track. I was running the A/C on low and radio while going through the wash.

Once free, I drove the car for several miles pulsing and lightly braking and it brought the battery back to down from 2 bars and all green. By the end of the day it was all but 2 bars and blue.

Did I get water in there somewhere that was causing problems, or is my 12V going out or is the "main" battery the traction battery on the display?

 

I checked it over the summer using the system check. I had let the car sit over night and tried it first thing in the morning. Since I had forgotten to turn off the A/C when I parked, it dropped pretty quickly and would have been considered as needing replaced based on the voltage reading. However, I discounted it at the time because I had left the A/C running and figured I was getting an invalid reading. I have not rechecked it since that time.

I have used this car wash two other times with both A/C and radio on while going through the wash with no issue. On this trip, however, I did have to wait idling for about 5 minutes while they rinsed off the truck in front of me. I did not have to do this in the past and wonder if it has any bearing on my experience today.

If I need to replace the 12v battery, I would rather do that now than get stranded later this winter. If it's the traction battery (again I don't know for sure what the "main Battery" icon on the display refers to), I need to get it dealt with while the car has less than 70K miles on it.

 

"I think that the HV battery had gotten so low that it was approaching
the HV System Auto-Shutdown, Tow-Me-to-the-Dealer state, but didn't get there... "

Yes, lucky me. I did have the presence of mind to shut it all down when I got the warning, but still worried I would not make it out of the wash. Couldn't imagine how they'd get a tow truck in there...

I'll recheck tomorrow, but may not get to post until later in the evening due to work.

 

Ok tested it this morning.

My values were 12.2 initially, then 12.0, then 14.0 in charging mode.

 

I tend to agree with you. However - this is the first time I have had to wait forever to get into the was and I was idling in D while waiting AND this is the first time I've had the undercarriage wash (which was pretty high pressure). It was just at the end of that wash that the car started buzzing at me.

I did notice today that sitting at a light the bars on my battery went from 1 from the top and green to 3 from the top and blue and that was a short light of less that 45 seconds. That alone concerns me, as it doesn't seem like it should be discharging so quickly.

Please clarify for me, is the battery on the display (the one with the bars) the traction battery or the 12v?