Question about hybrid battery

There are a couple ways to evaluate the HV battery prior to buying a car. There's a handful of apps available for your phone that can display module block voltages. The apps can even help you perform a battery test. You can even use the AC system to test the battery since the AC compressor runs off battery power. Don't forget to also check the brake system actuator/accumulator, as that can be an expensive repair also. Press the brakes 2-3 times until you here the brake pump start and immediately let go of the brake. Leave your foot off the brake and see how long it takes before the pump starts again. A GOOD pump will make you die of boredom waiting. If the system is leaking internally, the pump may start in just 10 seconds. Even 5 minutes, to me, is too soon, but could last for years of use.

 

Kudos to you for performing research BEFORE purchasing a Prius. As mentioned the high voltage battery or the brake accumalator are some of several known problem areas on Gen2 Prius. Others are the Combination Meter (speedometer) not turning on, failure of the inverter coolant pump and or the "heater" control (3 way) valve. Most of these problems do not happen to every car (at least not all at once). It is a good idea to have any used car inspected by your mechanic - preferably one with some hybrid experience.

Realistically the safest bet is to budget for the possibility of having to replace the hv battery in the next year- the original pack might last 5 more years or it could fail next month. If you want the car to be reliable then the best option is new battery modules. That would be around $3000 or more if a Toyota dealer installs it, to under $2000 if you were able to install them yourself (either Toyota or NewPriusBatteries.com).

That should give you 5-10 years of no worries about the hv battery. Anything else is a rebuilt or refurbished hv pack made of USED modules that may or may not have been cycled (discharged then charged several times to try an restore capacity) and matched. Refurbs might last a few years or a few months- they don't have a good track record.

Another thing to consider is that in quite a few parts of the world, theft of vehicle catalytic converters is an increasing problem- and the Gen2 Prius is a prime target as the cat can be quickly cut out and is high value to a recycler. You can read through the Gen2 forums for everything mentioned here.

The Prius can be a very good car, but you should have awarenes of what COULD happen if you own one.

Posted via the PriusChat mobile app.

 

Actually, your dealer seems knowledgeable and honest. Is it a Toyota dealer? If so, what would they charge to replace the battery if it goes out? Maybe you could get them to agree on a reduced charge for the labor to install when/if needed.

As TMR-JWAP says, there are apps to test the hybrid battery. You would need an OBDII bluetooth adapter that plugs into the diagnostic port under the dash. I use the Dr. Prius app with an OBDLink LX which is about $50 on Amazon.

Hybrid battery diagnostic and repair tool for Toyota and Lexus

 

corolla

 

For any used car, the biggest factor to consider is how well it was taken care of by the previous owner(s). If it comes with the maintenance and repair history, look it over and see if it’s been regularly maintained. If so, you’ll probably get a good car with minimal problems. If not, it’s a greater risk.