Replacing a Traction battery Module.

Thought I might post this so others might learn from my mistake in not cleaning my cooling fan.

I bought my 04" over a year ago used. Got a dirt cheap ($500) deal on it because it had over 200K miles, filthy inside and out and needed tires and one. Rear driver side had a CHUNK missing near the bead. BUT it also had a recently installed reman traction battery from a legit shop that reburbishes them!!! Having done weeks of research on Gen2's before shopping for one, I knew this was often the most expensive thing to fix. The seller said it was "still messed up" and that "he got scammed" and he needed cash. Car still runs but sometimes it just powers off and...stops, he can power it back on usually right away and drive. Hmm.

I go test drive the car and show up with an OBD scanner and DR Prius ap. No codes, battery health looks great, car runs fine. I buy the car. Curious about exactly how old the "new" battery is in terms of the miles he's put on it, I call the reman shop, give the guys name and the find the record. They tell me it was cash and carry, he bought it and planned to install it himself. At the time, they only sold to dealers and ASE certified techs. The seller was neither. The warranty is also void if not installed by a certified tech. They say he was very pissy about this when he picked it up and made a huge scene.

It's starting to become clear I've gotta check this thing out. Turned out the be a bad 12V battery connection. I'm guessing the pulled it during the traction battery install and forgot to tighten it. Hit the right bump, and you get a complete system reboot! He lived up a pretty rutted country road so that explains why it happened a lot to him I bet!

New tires and wheels, seat covers, and a LOT of carpet shampoo later and I've got a 47mpg fully loaded daily driver with cold AC!

Fast forward over a year with ZERO trouble. Then we had a 105F day and I get the red triangle and a traction battery trouble code. Crap. Run the DR Prius app and I show block 12 is WAY out of whack. I go to remove the battery and of course the fan ducting. Where I found a giant wad of dog hair blocking the cooling fan duct. My dogs favorite seat is, passenger side rear....

Turns out the one bad module got so hot it bonded itself to the modules on either side. I'll be replacing three module minimum. The other 27 modules (even the stuck ones) are at a very consistent 7.6v after several days parked idle. Bad cell was 6.2v.

So this was long and rambling but the point I guess is, clean those vents!

 

It's a small shop in Salem Oregon. They cited concerns the electrocution risks of unskilled customers working with the HV battery. What I REALLY guess is, they are just trying to make the money on doing the install job for themselves and then find other things to add to the bill.

I worked at an auto parts store with a small shop in the back for several years. We would do the "free" inspection promos to drum up business all of the time. It always worked. The HV battery pack is a fairly easy install. Easy way to get a customer's car into the shop.

But again, this is Oregon where they don't think people are smart enough to pump their own gas so....