Reverse Polarity

welcome! it's probably the fuse, but if that doesn't work, you may have fried the inverter. not to worry, you can pick them up for cheap on ebay. all the best!

 

Sorry to hear about your mishap. Interesting that the turn signal lamps light up in that condition.

Replacing all the fuses probably won't be necessary. For some of that money, you can get a cheap multimeter and use it to test fuses and see which ones (if any) need to be replaced.

Good that you spotted the fuses located right in the battery terminal. There is (I drive a Gen 1, so I'm extrapolating a bit to your Gen 2, but I'm pretty confident) another fuse rather like it (about 100 amp) in a main engine compartment fuse box, where that cable from the battery meets the DC/DC converter. There is a good chance you will find that you need that fuse.

If you're lucky, the fuse did what it's supposed to, fast enough, and your DC/DC converter itself is ok. You'll know soon.

You can find all your wiring diagrams on techinfo.toyota.com. They can be very helpful in troubleshooting because you will see where all the fuses are and what things are upstream/downstream of them, so you can make some diagnostic judgments based on what is and isn't getting power. Sometimes that is easier than getting access to the fuse terminals to test there (in some models at least, I think I've read that the DC/DC converter fuse has screw terminals that need to be accessed from the bottom of the fuse box).

As you are getting some dash lights and the power button ring when you try to power the car, at least some of the car's computers are probably getting power. That means if you have a scan tool that can read Prius computers (in this forum, Mini VCI is a popular choice, and it's cheap if you've got a laptop already), you can get the computers to give you whatever information they have about where the problem(s) might be.

Hope this helps!
-Chap

 

Where are you located. An independent Prius repair facility can keep your repair costs reasonable. We can try to identify one near you.

JeffD

 

As previously suggested, use the ohmmeter function of a digital multimeter to verify fuse continuity. Remove one fuse at a time and measure it, then replace. Use long nose pliers to easily remove a fuse.

In addition, look at the fuse links located in the main relay/fuse box next to the inverter, behind the driver's headlight assembly. They are in a ~5" long plastic box with a clear cover. Look for a burnt link, which would be the 100A DC/DC link. If you see that then the entire box with fuse links will need to be replaced. This is not a minor task.

 

I'm guessing that you're not going to find there are many (plural...) fuses needing replacement, outside of perhaps one or two key ones ... and fuses are testable before you replace them. I'd suggest consulting the wiring diagram to plan your attack on the most likely ones first (even if those aren't the most easily accessible).

One of the traps a person can fall into while doing diagnosis is that every other thing you disturb without needing to has a possibility of causing an additional problem. Even something that seems very simple, like pulling a whole bunch of fuses, might lead you to eventually discover, for example, one of those had a weak terminal that was never causing a problem before. Often the extra problem will be something really simple that normally wouldn't be hard to find, but it can be very confusing in the middle of trying to troubleshoot something else. So there's a good reason for trying to use a restrained hand while trying to track down a problem.

-Chap

 

hometown hybrids, ask for jess.

 

Yes, admirably cautious. In case you're curious later (you've probably already figured this out by looking at the old one you replaced), that fuse doesn't pry out, the terminals are bolted, but it's easy to get to the bolts just by unclipping and folding open the plastic 'doors' on the side of that housing. At least that's how it works on my Gen 1. Some years back I posted a photo; should be here, with one plastic flap open to show the terminal.

-Chap