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This One Trick Can Save Your Toyota Prius Traction Battery

There are many things that can cause a traction battery on a Toyota Prius to fail. Knowing this tip can keep your battery from potential unwanted failure.


When you mention Toyota Prius and traction battery in the same sentence, owners seem to perk right up. Well that is what I am doing right now. I found a simple answer to a complex problem that can keep your Prius from having battery issues.

Opening The Door On Your Prius Shuts Down The Cooling Fan

I did not know this was even a thing until I was in a hybrid training course not two days ago. In the course we discussed "ready" off, or things that can cause the car to shut down. This particular act is opening the door.

What happens is, Toyota does not want dirt to get sucked into the cooling fan and blown over the HV battery. This can cause dirt and debris to build up in the fan and over the battery so Toyota shuts it off when the passenger door is opened. Stuff like this is not covered under warranty.

Stuffed full 2007 toyota prius keep the battery cool

This became a big problem with taxi driver that would stand out with the door open signaling to others, they were ready to take customers. They would get back in and the car would no longer "ready" on due to an overheated battery.

What You Can Do To Prevent Battery Overheating

You will see threads on blogs, forums, facebook pages, and all over about cleaning your HV fan battery. There are gobs of youtube videos as well out there. Keeping the fan clean will allow adequate air flow over the pack keeping it as cool as possible for you given surroundings.

Dr Prius App Data 2007 Toyota Prius

The other thing to do is probably not leave the door open when the car is in "ready" mode, and especially on a hot day. Keep the a/c on in the cabin as well while driving, to keep you relaxed and sending cool air back to that battery. It will thank you in smiles per gallon. Crazy how one simple thing can give you such a headache


If you remember nothing else from this article, just remember this. Your Prius is a solid car but it still needs love. Clean the fan, use quality fluids, and for heaven's sake, keep the doors closed when it is hot outside. Enjoy your weekend everyone.

As always, feel free to reach out to me on social media if you need help. Have a great start to your weekend and I will see you in the next story. I wanted to tell you all be sure to check out my favorite 3rd gen accessory right now which is the Nimbus Phone Mount, found on Amazon.

Check out my other story Why the first generation Prius is better than either generation Nissan Leaf.

See you in the next story where I am discussing why Carista is the best $20 tool for your Toyota Prius.

Also Watch New tech means more MPG from your Toyota Prius and Click to Subscribe to Torque News Youtube Channel for Daily Toyota Prius and Automotive News.

Peter Neilson is an automotive consultant specializing in electric cars and hybrid battery technologies. He is an automotive technology instructor at Columbia Basin College. He holds a Bachelor of Science in Automotive Service Technology from Weber State University. Peter is also an Adjunct Instructor of automotive technology at Columbia Basin College. Peter can be reached on Linkedin and you can tweet him at The_hybrid_guy on Twitter.


Merlin Valencia (not verified)    September 15, 2019 - 4:42PM

I learned that the battery likes to stay at the same temperature as a human being so if you are uncomfortable the battery is uncomfortable so you should use the AC to keep cool