Don't believe everything you read on the web.

From the Department of Dangerously Wrong Information comes a horrifying piece on Yahoo's open content network, entitled "What New Prius Batteries Cost and How You Can Save Thousands."

It looks like one of many articles that respond to consumer worries over the cost of replacing the high-voltage battery pack in a hybrid car.

This one, though, is something entirely different. It's actually shilling a website that encourages people to buy parts to rebuild their own batteries. And it's riddled with errors, some of them potentially expensive or dangerous.

2012 Toyota Prius V

2012 Toyota Prius V

CLAIM: "At some time or another all Prius owners have to replace their batteries."

FACT: This is likely true if you're talking about the 12-Volt starter battery. It may need to be replaced a few times over the car's life. It's not true if you're talking about the high-voltage nickel-metal-hydride battery pack that's an integral component of Toyota's Hybrid Synergy Drive System.

That battery pack is designed to last the lifetime of the car. While an individual pack may conceivably fail, it is not considered a service item, and the vast majority of packs replaced at Toyota dealers are due to accident damage. Most early Priuses are still going strong with their original packs.

CLAIM: "Prius batteries cost you around $4,000."

FACT: No, they don't. Replacement packs for 2001-2003 models are $2,299, and for 2004-2009 models they're $2,588. Labor costs may add a few hundred more dollars.

CLAIM: "You have to do this every 8 years or 140,000 miles."

FACT: No, you don't. Toyota must warranty the pack for either 8 years / 100,000 miles or 10 years / 150,000 miles, depending on which state it's sold in. (California and states that have adopted its emissions standards have longer intervals.)

But expiration of the warranty doesn't mean mandatory replacement. When your engine goes out of warranty, do you have to have the dealer install a new one?

Prius Battery Rebuild Guide ad

Prius Battery Rebuild Guide ad

CLAIM: "If you don't know how to rebuild the battery yourself, you can get a battery rebuild guide online that will show you how to rebuild your batteries step by step. When you do it yourself, Prius batteries cost under $500 to fix."

FACT: Here's the sales pitch, for a website called, which the author helpfully links to--twice--in the next paragraph. Clicking through several more screens, you get to an offer for a book called "Prius Battery Rebuild Guide," which will cost you $49.97. It's not listed on Amazon, so we presume it's privately published.

Shot through with typos, the promotional page for the book claims that "Many of the customer's set aside a Saturday during one of their less busy weekends and take care of the whole thing in that one day."



Now, you might well choose to rebuild your own Prius battery ... if, say, you've previously converted your car to electric power. Or you customarily disassemble and rebuild high-voltage components. Or you have a background in electronics maintenance.

But if you're an average Joe (or Jane) who tops out at replacing light bulbs, or you're not too sure what to do when a circuit breaker trips, we would very strongly suggest that this is not the project to start with.

We're not against someone selling how-to books online. What we are against is blatant misinformation about hybrid cars, what they are, what they cost, and what buyers can expect.

And if the book has as many errors and lies as the websites used to promote it, we can only fear for the safety of anyone who follows its instructions.

Oddly, author "Gulliver O'Neill" has been a contributor for only a week, and has written only a single article for Yahoo. And a quick Google search shows that he's reprised the same article at eZine Articles and ArticleS Base.

And we're saddened to see a venerable online name like Yahoo letting a piece like this appear under its brand. Caveat emptor.