Speedometer & Rear cam nonfunctional, fast hybrid battery charge/discharge, check engine light on

Hi all,
I have a 2008 Gen. 2 Prius with 142800 miles on it. I bought it just under a month ago, and now I'm having a bunch of problems. I have all of the car's service records. The most recent official service record is from 11/27/2023 and it says that the car's check engine light was on and that diagnostics revealed that the Hybrid Inverter pump was inoperable, coolant was low, and that there were random misfires. I think that I've also experienced misfires as the car will sputter when stationary or parking. They replaced the spark plugs, drive belt, inverter pump, and coolant.

The car has been well maintained including regular oil changes, filter replacements, etc...
The service was performed at a Toyota dealer which would mean the work/parts are within warranty; however, the dealer is in VA and I'm in NY.

I checked the 12V battery's voltage and it was at 11.6 with lights off, 10.9 with lights on, and got up to 14 with the car's engine on. The last time the 12 V battery was replaced was in 2016. My most recent state inspection indicated that the 12V battery health was at a 9 on a scale of 1-15.

I've been getting about 30-35 mpg, and the hybrid battery will appear to be charging quickly and then rapidly discharge. When turning on the car in the morning after sitting overnight, it is shown as having no charge. I know that several battery cells were replaced and that the hybrid battery was in good health when checked before purchase.

The speedometer, rear cam, and check engine light problems all occurred this morning as I was getting ready to bring the car to the dealer to get the 12V battery replaced. It's like the car knew I was going to get it serviced LOL.

I checked with an OBD meter before purchase and after driving a lot and nothing showed. Nothing showed when I got it inspected as well. I'm a bit confused and sad that all this is happening after just purchasing it this month.

I trust all of your guys' judgement and would love to hear your thoughts. Thank you.

 

Bingo. The dealer tested the battery and said it failed the load test, so I’m going to replace the 12v. I have to get a bluetooth OBD, so I’ll update this shortly when I’ve got a new battery and a Bluetooth OBD. Thank you!

 

I got the 12V load tested and it failed, so I’m replacing the battery. I also purchased a Bluetooth OBD and I’ll investigate further when I get it. Thank you for sharing this info. @mr_guy_mann

 

Okay, now for some updates. I got the 12V battery replaced and the speedometer and rear cam are fully functional. There is no more check engine light and no codes. I used the Dr. Prius app and everything looked solid to me… but please let me know if you see anything suspicious here.