Im am super close to buying an 06 prius with 117k on the odo. i have access to scan tools and stuff (i am a technician of sorts) attached you will see pictures of the battery status when the car is sitting without the A/C on and without the ICE on. my believe is that the numbers are all relatively close and no abnormal numbers for each cell so the battery is good. any incite into this would be great. i have a basic idea at what im looking at but not 100% sure how this applies to this car or what "good" looks like. (dont mind the ugly face I am making in the reflection, it was bright outside)
The static voltages tell you little about the battery health. What you want to see, is how each pair of modules (block) behave under load and/or discharge. Use the rudimentary test in this thread: How to test HV battery state of health on your Gen 2 (answer) | Prius Chat to see this better. If your scan tool has a data logging function record the test and graph as per the graph shown in post #2. (Don't worry about the yellow or cyan lines, they are calculated.) The data point you want to capture are: Batt Temp 1, 2 and 3 Max Block Voltage Min Block Voltage Max Block Number Min Block Number Battery Current Amps You primarily want to look at the divergence of the high/low voltages over time and the time it takes to go from 80% to 40%.
If the car has lived up in the NE it's whole life, that's good for the battery but it's still 12-13 years old. Only buy with replacement costs in mine because it will need one; sooner or later. 117k miles is nothing for the drivetrain. A grid charger can help maintain the old pack.
Thank you for all your help. I will see what I can do with this scan tool. It's a bit cumbersome to navigate.
You could use Torque Pro app along with a wifi OBDII reader and log the data. Cost you less than $50 total. Have someone else drive it while you watch the live data. Or fill the battery pack by "Powerbraking" the car while in drive and watch the data. Then drain the pack while driving in reverse up a steep hill several times. Call me if you want to hash out the details. The pack might be fine today but... Basically a car of that age you will be replacing the battery pack in the next couple of years. Count on it. For sure. So set aside an extra $2000-$3,000.
I can save you alot of time. If you roll into Burger King with 2 blue bars and by the time you roll out of the drive through you have one purple bar the hybrid battery is showing its age and at the very least needs a rejuvenation. Oh and mileage is crappy too.
That seems like an extreme statement to me, unless you have access to Toyota's data about battery failures.
