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Can You Have No Codes And Still Have A Problem With Your Toyota Prius Battery?

If you feel you have done everything to your Toyota Prius but are still not getting the expected fuel mileage, it is time to examine what your battery is really telling you.

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Is your Prius getting less than 40 miles per gallon? Have you tried "everything" to get your gas mileage back up, but "nothing has worked?" If you have answered yes to these questions, you are not alone. There are plenty of Prius owners who are suffering just like you. The worst part is your Prius is acting "normal" because there is no trouble code to tell you otherwise.

I want to cover today how you can fix your fuel economy issue you are having even when your Prius does not find the fault by itself. Here is how to recover lost MPG and restore your faith in your Prius.

The "I Have Tried Everything" Approach
In a conventional car, when our fuel economy suffers, we tend to revert to what we used to know about cars. Sensors get dirty, carbon buildup plagues our intake ports, or maybe our tires are just underinflated.

Whatever the case may be, you can only go so far with items like those on a hybrid. What most hybrid owners are failing to understand is what crucial role the hybrid battery plays in overall system health and fuel economy.

2003 Toyota Prius Hybrid monitor

We often think that the battery is just an expensive component that, when it fails, can cost us to rethink the hybrid life. Many times we will do anything else other than look at the battery and deem it failed, and why? Because it did not set a trouble code, so it is okay right? Wrong.

If you have gone through all the trouble of cleaning your EGR, putting injector cleaner in the tank, changing spark plugs, airing up your tires, and anything else you can think of, you need a new strategy. Usually, this is not wasted money on proper maintenance, but what will it take you to realize you are living the definition of insanity?

If you have been through the wringer with your Prius and still are seeing less than a decent fuel economy range, here is what you need to know about your battery.

Your Hybrid Battery Goes Through Life Phases
I have written a lot of various articles on hybrid batteries, but not one quite like this. There are several reasons I keep writing about hybrid battery maintenance. You need to know that you can get more out of it by merely maintaining it.

Most hybrid owners are not aware of what their battery goes through over the life span. I want to explain to them each and some signs you will see from each phase of life. (image courtesy of Hybrid Automotive, Prolong Systems)

Hybrid automotive phases of life hybrid battery

Phase one: The honeymoon stage. This stage is the best one by far. It is where the battery is happy, healthy, and new. There are no problems because it is functioning as designed. You will not notice any issues here because there are none.

Phase two: Your Prius may not feel as snappy, and you have seen some decrease in your fuel economy. You shake it off and blame it on tire inflation or weather changes, so you do not care. The problem here is this would be the best time to start paying attention to your battery and reconditioning it. You have the least amount of wear in this phase.

Phase three: Your Prius has dropped at least 5 miles per gallon or more. You are experiencing negative recalibrations on your dash monitor. Forced charging happens all the time now, and the car seems quite a bit slower than it used to.

These are typical battery phases that every Prius owner will go through. The problem is, not one owner will take this as a sign that the car is trying to tell them something. When you get a trouble code, usually it is too late to do much if anything about your hybrid battery. Then it happens—the triangle of death, the master warning light.

The thing is this if you have "done everything else," and you still have no idea how your MPG is so low on your hybrid, do this. Get Dr. Prius, do the life test, and then after it tells you that you have almost no life left, recondition your battery or get a new one.

Not only will you learn quite a lot about your car, but your faith in it and humanity will be restored.

If you are willing to spend hundreds of dollars on other maintenance, why are you not willing to do the same for your hybrid battery? It makes sense to take care of it like any other part of your car.

Sure you can put a new battery in your car every 15 years or so, that is a great option. But you will also steadily lose fuel economy over that time as well. If you maintain it, you will see a steady fuel economy numbers for longer over the period you have the car. It makes sense, and it also will cost you less over time to recondition your battery.

Chances are by the time you sell your Prius, you will have kept it in peak operating condition and will have gotten the best fuel economy possible. Stop pulling your hair out and get a new battery or recondition yours to see the fuel economy increase you are looking to get. So the answer to the question is yes you can. So what are you going to do about it?

Thank you, everyone, that is all for today. I look forward to seeing you in the next story. How To Deal With A Toyota Prius C1256 Failed Brake Accumulator Trouble Code

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Peter Neilson is an automotive consultant specializing in electric cars and hybrid battery technologies. He holds a Bachelor of Science in Automotive Service Technology from Weber State University. Peter is also an 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. Find his page on Facebook at Certified Auto Consulting. Read more of Peter's stories at Toyota news coverage on Torque News. Search Toyota Prius Torque News for more in depth Prius coverage from our reporters

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Leah Markwell (not verified)    May 7, 2020 - 5:09PM

Hello Peter,

My name is Leah and I work for Bumblebee Batteries her in Oregon. We build hybrid batteries to order, new production and rebuilt.

Do you sell add space on your web page? If yes how much do you charge? I have been reading it since I started in sales and marketing here and find it very informative.Please let me know.

Thank you for your time. I hope to hear from you soon.

Leah Markwell

I was wondering if you sell ad space in your

Peter Neilson    May 8, 2020 - 5:42PM

In reply to by Leah Markwell (not verified)

Hi Leah! Yes, there is always space. Please email the editor at [email protected]. Let him know who you are and that you reached out to me. He will get you going. P.S. I would love to come take a tour of your facility and do a write up on it. Good exposure! You just say when. I am 3 hours away.