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The Dealer Wanted $4,400 To Fix His Hybrid. He Did It Himself For $7

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The dealer wanted $4,400 to fix his Toyota hybrid. He did it for $7. Show this story to every person you know who claims you can't fix new cars yourself anymore.

This story popped up on Imgur (and Reddit) via our own Oppositelock. I'll post the key elements here, but I encourage you to go over and see scoodidabop's full post right here of how he pulled off this job. It shows the incredible power of a basic understanding of how electronics work.


So this guy got an error message on his dashboard with a "Check Hybrid System" warning. He'd just bought the car secondhand without a warranty, but he took the car to a dealer in the hopes that the car was giving him a false reading.


He was not so lucky.

I took the car into the Toyota dealer Monday morning and after about 4 hours the service center called me with the news. "Are you sitting down?" he said. "Should I be?" I replied. "Um. Yea I think so" he said. "Your hybrid battery has 'gone bad' and needs to be replaced. It's a $4400 job."

I just bought this car! $4400? That's more than half of what I paid for the whole car. Funk dat. I called Toyota's corporate customer support and after a few days they generously offered a $500 credit on the repair. My Camry's hybrid system is within range of the warranty in terms of years, but exceeded the mileage allowance. I'm starting to feel sick.

His back against the wall, our hero realizes that this battery pack probably is just like the one in the Prius he used to own. That is, the large battery pack is likely made up of a number of individual cells. If it is, he could just replace one bad cell and fix the whole car. "There's only one way to find out..." he writes.


scoodidabop pulled the battery himself, feeling confident to do so after watching this instructional video, wearing gloves, and checking every bare connection with a meter before handling it. Only with these precautions did he disconnect the high-voltage supply. This is serious business. He then got to work.

I remove all the buss bars (the orange plastic things - there's copper connectors in there that connects the batteries in pairs and in overall series) and start testing the batteries individually...8.11v, 8.10v, 8.10v, 8.11v... etc... all cells looking good so far.


These little lights weren't enough load so I used a spool of magnet wire. More on that in a sec...

Look how bad those copper connections are. So corroded. That can't be good.

I tested every single cell 3 times. All at normal voltage. I waited 2 hours and retested. Again - all normal. What? That's weird.

I hooked a spool of copper wire (to add resistance/load briefly) and checked the voltages again. This test is also done one single cell at a time and you measure the voltage drop when a load is applied. The the voltage has an extreme dip then you're likely dealing with a bad cell due to high resistance and efficiency loss. I found no issues with any battery cell.

Let me say that again: I found zero issues with every single battery cell in my hybrid battery pack. Wut?! Replacing this pack would be wasteful since it's operating within all nominal values.

Is the corrosion on those connectors bad enough to throw off the operating voltages of the whole system? Well it looks pretty bad. Let's pop all of those buggers out and clean them up...


So he did. And it worked.


He soaked all his copper connectors in a vinegar solution, scrubbed them gently with steel wool, then soaked them in a baking soda and water solution to counteract the vinegar's acidity. Then he did the same with the steel nuts that hold the copper connectors on. The whole thing took an hour.

When he put the whole battery assembly back together and put it back in the car, his error codes were gone. Poof.

When the error codes came up last weekend the gas engine ran 100% of the time and the hybrid system was non-functional. Now the battery pack is charging and discharging correctly, the warning lights are gone, and everything looks great thanks to improved current flow over the buss bars! This kicks ass!


He sums up the experience briefly and beautifully.

Ha! Suck it! You work again you freakin golf cart!

Car enthusiasts tend to complain that automobiles are getting too complex for the everyday person to fix them. Hybrids are the newest, the most confusing, and the most hated technologies seeping into the mainstream.


Maybe all it takes is a little understanding of how these new systems work and we'll see that repairs are far from impossible, as we've been led to believe.

(Hat tip to noise!)

Photo Credits: scoodidabop

Again, let me encourage you to check out the original posting on Reddit right here. It's so very, very heartening.