Post mortem hybrid battery questions

Hundreds of miles. Don’t rely on any of those 4. The HV bat starts the gas engine by initiating rotation, so it’s essential. But if you’re ok with the gas engine doing all the work you can probably skate by with a “bad” but not dead HV bat. However your days are numbered. I’ve run one of my Priuses in probably the same or similar condition for maybe 3000 miles and 4 years.

 

You could try the Prolong System to revive the hybrid battery.
Something you can install yourself with a few simple tools.
And some mechanical ability.
It's about 4 or 5 times less cost.

 

If you buy an OBD2 reader you can clear the error codes as they come up with a phone app like Dr. Prius App... And you'll be able to go for weeks or months before the pack starts running too hot to keep using. Here's buyer's guide for OBD2 reader: Hybrid battery diagnostic and repair tool for Toyota and Lexus I've had packs I've diagnosed in my car and done this routine many times. Electricity behaves oddly too... Some days I'd clear error codes several times in a day and then sometime I could go weeks without an error code.

Also some people luck out and replace one of the 28 modules, which cost $35 each used and then get a year or longer without issues.

 

I would replace the spark plugs, air filter, clean out throttle body, traction battery cooling system - if your handy. This will extend the life of the car and give it a chance to be reliable - since your on ICE much more of the time.

 

FYI, I had similar hybrid issues to you. Here’s my experience if it’ll help you in a decision.

I built an DIY grid charger and did a 3 cycle recondition. That fixed it for a few months before block 9 kept failing and I had to reset using Dr Prius on almost every trip. Note that the SOC resets to 20% or so, so even though you can still run, the engine will kick in continuously and will overcharge the battery, causing it to heat up very quickly. You may have to pull over to let it cool down so you don’t destroy your battery.

I bought 5 modules from eBay for $30 each, intending to replace a module from block 9. Turns out I had 3 modules that were failing (capacity < 1.5Ah), and 2 of the eBay modules were weak (capacity < 3Ah), so I ended replacing 3 modules. It’s been working great so far for a couple of months. Car runs like it did before the hybrid error. Next time I would get modules for a reputable dealer recommend in this forum, instead of an unknown eBay seller.

Spark plugs are dirt cheap and straightforward to replace, though painful because you have to take off the cowling on a Prius.

Same for a window motor. Relatively cheap and very straightforward to replace if that’s your issue.

Prius brakes last a long time. I’m still on my original at 130k and 13 years. Not sure what you mean by almost shot. But there is a known brake booster problem that you can get fixed for free if your car is < 10 years and 150k (which you are well under at 116k).