Hello everyone, Wondering if the Prius will give signs of an aging main battery, or will the car suddenly turn into a paperweight at an unexpected time if the main battery dies? 2010 Prius, 120k miles - running strong. If the 12 vlt battery dies, there is no warning. Suddenly you can't start the car, period. What is one to expect on an aging Prius main battery? --- Side note: These are easy rnough to replace as a diy project, right - so long as you obtain new cells? Where are they purchased and about what do they cost?
You’ll see the mpg decline and the battery will begin to cycle from full to low faster. This is subtle over time, so you won’t really notice it. I got the Prolong equipment and that helped keep the battery like new. Good luck .
i don't recall anyone reporting a car just dying out of the blue. even if it throws a code, you can usually disconnect the 12v neg for a minute, and it will restart. new batteries are all over the place from around 2k -4k depending on dealer and install. you can get a new aftermarket from a member here for $1,600. and there are installation videos on youtube. it is heavy and cumbersome, best with two people. and you have to be careful and methodical, but it is not extremely difficult.
There are ALOT of YouTube videos on the battery swap and module replacement. I’d watch them so you are up to date on what’s required . If you do the Prolong harness and get after it before the battery fails, all that is involved is a harness install with no battery removal required .
Maybe you want to remove it to clean up the bus bars, any other connection points? Or does the corrosion tend to be on the outside, not so much on the contact surfaces?
The busbars and fasteners are installed dry. Rust eventually grows in-between the dry contacts. It's best to replace with new parts after several years of use. Spread Oxguard on both sides of each busbar to help prevent oxidation. Pixel XL ?
The 12v battery can be load tested at any auto parts store if you take it out. Keep a lithium jump starter on board and you won’t be stranded by the 12v. If you leave reading light on or shutdown the car and then sit waiting for an hour you will need a jump. A weak 12v battery has limited amp hrs to run offline loads. Know how to jump it from under the hood. The lithium jump is fine as long as you can get to it when the hatch won’t open. The hv battery will start giving lower mpg by maybe three or four mpg and will go from high to low just sitting at a stoplight. You may hear pinging at initial acceleration with a very low hv charge. With 120k you should be good for a few more years. The Dr Prius app claims to load test the hv battery and give you an estimate of its lifespan. The thing that will strand you is the inverter. Not much you can do about it except have your roadside assistance number programmed in your phone. Been there done that.
