what's the bare minimum assembly for the HV battery to start and run prius

This may be a first. I’ll be interested in the answer as well. Be careful around high voltage!

 

You need to torque the nuts to 48 INCH pounds.

Otherwise you have no connection.

 

That takes all the fun out of it

 

Well if time is no object, do one thing at a time until it starts.

But the nuts would be first on my list .

 

Welcome to PriusChat!!

What OBD2 codes are being thrown, as they will point you in the right direction.

Not sure which two bolts you used to "hold the battery down", but the HV battery will need to be grounded to the chassis.

 

You need to put all the nuts onto the battery modules. Without that, there's no connection.

Be sure not to kill yourself when working with high voltage

 

1) Competency.
2) Laziness is counter productive, and may be detrimental to your health.

 

There's an old joke about a half a glass of water. Optimists say it's half full, pessimists say it's half empty, and engineers say it's too big of a glass.

The engineers who designed the battery had a reason for every part on there, and trust me -- engineers don't waste time and money on bling in the hybrid system because it would add unnecessary weight. Nothing is there just for looks. As @JC91006 said, it won't work if you don't tighten every fastener.

 

In the time it took you to post here and wait for a reply you could have put everything back together properly, be up and running, and not have to post here...

 

This sounds like the orange safety plug has not been properly installed. It's a common mistake for first time battery work. To install the orange plug, push it in, flip the lever up, and then push the lever straight down. It's that third step that trips up newcomers.

As others have said, the case needs to be grounded to the car body. It sounds like the two bolts you installed took care of this. Of course all the nuts need to be installed and torqued to 48 inch pounds on every battery module. Plug in the computer connections and you should be good to go for a test run.