Should I buy a 2007 Prius with hymotion installed?

Hymotion is not in business anymore. Their packs are reliable if you treat them nicely, meaning do not fully charge, and do not fully deplete. However, they allow you to squeeze every drop out of the pack if you want to, and most people do which in turn destroys the pack fairly quickly (< 1000 recharge cycles, or if 1 time per day, 3 years). If you know nothing about how it was treated previously, and how many miles are on the conversion, I would run away and leave it to someone who has time to tinker when it inevitably fails. It is a great system with lots of holes for user and self inflicted destruction possibilities. That's why they are no more...

 

maybe offer the dealer what it would be worth without the system?

 

Yep. Even though the Hymotion system seemed the most reliable out of the plug-in add on packs, some have had failures and yes, it's no longer produced and A123 Systems even filed for bankruptcy, but the remnants aren't dead.

I would basically not pay any more than for a car w/o it, because if it fails, it may not be worth the expense to get it fixed. If that's the case, remove it, instead of carrying around dead weight.

 

I thought the Hymotion system actually replaced the traction battery with their own LiFePO4 version (A123 cells), so there is no NiMH traction battery anymore. So you cannot remove it without buying another normal traction battery.

 

No, it doesn't. At least not from my re-skim of REVIEW: Hymotion Battery Plug-In Prius | PriusChat.

 

Very nice. In that case, go ahead and buy it!

 

We were Hymotion's first dealer back in 2007. I have been driving my conversion since then with very few problems. First of all the Hymotion system is quite nice. I am not an avid eco driver but I still regularly get around 75mpg driving up and down the hills of San Francisco. Like all new technologies it has had it's share of teething issues. It will not be as trouble free as the Prius itself. If you are not interested in at least a certain level of DIY activity I would not take it on. That doesn't mean you have to want to put on the high voltage linesman gloves and dig but it does mean you will need to educate yourself on how the system works, how to maintain it, etc. Where are you located? I can maybe suggest someone nearby who knows something about the system. If the system fails entire you can still get a rebuilt system for around $3500 installed depending on where you are located. Feel free to email me directly if you have any questions:
[email protected].

 

Does the Hymotion system use OOG mode?