12V battery, maybe damaged by shop?

Long story short ... I took my car to be tinted and I think the tint shop ran down the 12V battery and then "jumped" it without my knowledge. How do I know? I replaced the factory battery myself with a Optima yellow top back in August without any problems. Then I got windows tinted in October. A few weeks later my car begins showing signs of low 12V battery (i have other posts on this). So I go into the rear compartment to check battery connections and find that (1) a plastic tab has been broken off the trunk decking that covers the battery, and (2) the red plastic cap that covers the positive terminal has been yanked up and bent out of shape. The tint shop is the ONLY place my car has been since replacing the battery myself. And I definitely did not leave it in that condition.

Now, some questions:
1. Could the new battery now be damaged if improperly charged? (like not trickle charged) How would I test?
2. Why might it have taken 3 weeks for the battery to show signs of loss of charge?
3. Are any other electronics or circuitry put at risk if the 12V is improperly charge? If so, what?

Thanks for any feedback. I'm annoyed.

 

Thanks for the responses. I think my 12V battery is cooked. Crossing my fingers that nothing else was damaged, aside from some bent up plastic bits in the trunk when they forced their way into the battery compartment.

One more related question. Is it normal to see the red warning triangle* (!), even briefly, at startup? I don't recall ever seeing that until recently. I know the other warning lights flash on at startup, but I thought the triangle-of-death does not illuminate. (somewhat confirmed by this thread)

Ugh. trying to figure out what these idiot tint guys did is giving me a conniption fit. I just bought a trickle charger from Sears. Now to give the 12V a good charge then see if it holds.

 

Thanks for the responses. Have I mentioned how great this community is?

I will definitely report battery voltages after I check tomorrow morning (~12 hours from now). I drove around all day today so any readings now could be misleading. I should let the car sit for a few hours.

Also FYI, here is the cheapie trickle charger from Sears that I picked up today. It ought to do the trick(le) . First I'm charging up the factory battery that I replaced in August and has been sitting in my garage since. A bit of a test before connecting it to the car.

I'm disappointed that the tint job I was excited to (finally) get done has now left a sour taste in my mouth. I will consider myself lucky if it's only the battery that was damaged. I hate that the tint shop did not fess up and needlessly caused damage. Plus, I'm completely type-A about things so this is driving me bonkers.

 

Alright, I let the car sit overnight. As expected, the voltage readings are quite low, especially considering this is a new 12V Yellow Top. I took readings using MFD in maintenance mode and via ScanGuage.

1. 9.7V MFD | 9.6V Scanguage
2. n/a - the MFD actually shut off! Presumably because voltage was too low. | 8.8V Scangauge
3. 14.3V MFD | 13.9V Scanguage

Next step, tonight I will trickle charge the 12V overnight allowing it to reach full charge (I think I recall someone saying that 12.9V is the maximum). Then I will drive normally for a couple days and report voltages again. I expect the battery is ruined and it will only temporarily hold a full charge.

Seems like a forgone conclusion that the battery needs to be replaced. Only after that will I be able to determine if any additional damage has been done to electronics, etc. I sure hope not. This stinks.

 

Great tip! I noticed the ring connectors in the box and had the same idea. Nice to hear from someone already doing it with good results.

 

Whew. I sure hope you are right.

Status update: The battery completed charging this afternoon/evening. It took ~6 hours. After it finished I checked voltages as before and readings were nominal (but I left the sticky note in the car). The dome lights were noticeably brighter, the car started without <!-triangle>, and all the various pumps and motors just sounded more peppy, both at startup and shutdown.

I'm now going to let it sit overnight without the charger and then re-check voltages in the morning before driving to work. I'm expecting to see a low battery in the morning. I'm curious how much parasitic or "vampire" draw is normal for a Prius, and how much charge is lost simply due to a toasted battery. A question for a later time ...

 

Quick update: I replaced the 12V battery and everything seems to be back to normal. The car powers up without the <! triangle>, no more "pulsing" feedback in the brake pedal, and all voltage reading on the 12V are within tolerance. (12.5 or so in Acc-Only). There appears to be no other damage.

I also followed PriusGuy32's suggestion and attached the ring connector wire harness kit that came with the trickle charger and left the connector sticking out of the floor cover for easy access. I topped off the replacement 12V battery before starting up. Works great.

(An aside, I stopped by my local Toyota Dealership over the weekend to inquire about odd startup behavior indicative of a failing 12V battery. The service tech stated that <! triangle> at startup was "normal". Based on discussion here I don't think that is correct.)

I went back to the tint shop to sort out the situation with the owner and left them with some advice on how to (or how NOT to) treat Prius while working. I'm certain they drained the 12V battery while working on my car, then applied too many Amps to quickly recharge the 12V battery, directly to the battery terminals, which ruined the battery. (They didn't know about the battery terminal under the hood).

Thanks all for the helpful assistance. This was a good learning experience.

 

Aren't there fuses between the jump point and battery that would be bypassed if charging directly to the battery terminals?