2005 Prius Traction Battery 130F

As the titled says, my traction battery overheated (to at least 130F) and the triangle of death and a couple of other orange lights came on. I have a 2005 Prius with 206,000mi. After this happened, the car was still driveable and I was close to home. When I got home, I plugged in my Veepak ODBC and ram Dr. Prius which showed 130F and an error code P3000 P0A82. The battery is a Green Bean installed 7/7/2021. Here are the troubleshooting steps I've performed:

• Used Dr. Prius to clear the error. I drove the car again and the warning lights did not come on. However, the battery heated up to 121F. As far as I could tell, the battery fan did not com on.
• Got home and took everything apart so I could visually see if the battery fan was turning.
• Checked the hybrid battery vent and black air tubes. I actually took it all apart and verified there was no dirt/hair or other obstructions.
• Checked the squirrel fan/hybrid battery fan. It was very clean from when I cleaned it a couple of years ago.
• Turned on the car and used Dr. Prius to cycle through different battery fan speeds. All speeds worked which were based on the sliding temperature I moved in the Dr. Prius app.. However, at the top fan speed, the fan turned off after a few mins (this may be normal operation...idk).
• Ran a Life Expectancy test using Dr. Prius. It reported the battery had 60% left.

What in the world could be wrong?

 

@Mendel Leisk , I am reasonably sure that the overheating hybrid battery caused red triangle,etc as the codes it threw pointed to a generic hybrid battery problem P3000 and a problem with the fan P0A82 (Hybrid Battery Pack Cooling Fan 1 Performance/Stuck Off). But I could be wrong. Dr. Prius displayed the temp in red. Then it changed the.color to green when the temp dropped below 120F.

@bisco , the vent grill is clean as a whistle. I'll need to do a 25min drive to make sure the fan comes on again. I have taken the cover off so I'll be able to see the fan spinning.

It may have to do with its temperature sensor. But I don't know where or what part that is on the hybrid fan system.

 

Yes, the fan is very clean. It's white. Thank you!

 

That is a very interesting hypothesis, @Brian1954. Thank you for your thoughts. I also thought this might be a possibility. I used Dr. Prius to perform a Life Expectancy Test today, which consists of reving the engine to fully charge the battery and then keeping the current use (I think) steady for 5-10 mins by turning on the headlights and AC. Thats where i got the 60% life expectancy value (see attachment). It didn't report any bad cells, but this could have been a fluke.

I am attaching the Dr. Prius screenshot from when it overheated and the red triangle of death appeared with a couple other lights - on my way home. When I got home 2 days ago, I ran Dr. Prius and saw the over-heated battery. It occurred to me that there may be a possibility of fire if the battery gets too hot.

 

Yes, I have a lifetime warranty on the Green Bean battery. It may be that I need to run more tests...drive it for 30mins to see if the fan comes on or if the battery overheats again.

 

I just wanted to thank everyone for your expertise. I drove the 2005 prius today for about 30min. The battery fan came on and its speed even varied. The battery did not overheat. I might have to drive it for an hour. I have attached a pic of my battery fan and the battery. I circled 3 holes on the battery that air is being blown out of. I guess this is normal??

If it overheats again, it may very well be an indication that the hybrid battery is going bad. Thanks again!

 

I have covered the 3 holes on the hybrid battery with black electrical tape.

Hmmm, I didn't notice the green corrosion on the orange wire until you mentioned it. I'm not sure this was the problem as the battery fan was powering on, but corrosion is never good. I'll look into the separate cracked body filler issue. I'll be driving the vehicle for about 90mins this weekend so it'll be a good test.

 

Update: It may be likely that the corrosion on the green wire is causing my battery fan to run intermittently. Today, I started driving and the battery fan came on when I started my car - the battery temperature remained low throughout my drive. This happened bc I had Dr. Prius running and set the battery to run at max speed.

However, when I drove back home, the fan did not come on and the battery temperature rose to about 110F. I was not running Dr. Prius.

I found the battery fan wiring diagram in another post. It appears that the battery fan is controlled by voltage.

A temporary fix is to run Dr. Prius and set the fan to max. A permanent fix likely means splicing wires that have corrosion.

 

I don't think covering the 3 battery case holes with tape did anything, btw.

 

Thanks, I went ahead spliced the black wire and the brown wire bc there was a lot of corrosion. Unfortunately, the battery is still overheating. I saw the fan come on (at a very low speed) when I started the car. My guess is that the fan is not registering the voltage changes to change its speed. Again, if I run Dr. Prius, I can set the fan to max speed while driving.