02-10-2021, 08:27 PM
At least in the 2004-2009 generation, leaving the light in the luggage area on was a common source of battery drain.
Also, given the Prius design, you shouldn't need to actually drive it to charge the 12V battery. If you just turn it on in "Run mode" ready to drive but leave it in Park, it should charge the 12V battery. There's no alternator, the ICE doesn't need to actually be running. The 12V system is powered through an inverter from the traction battery, and that battery gets recharged by the ICE as needed.
That may or may not solve the underlying problem. If he's only driving a short distance/time then a new battery will likely result in the same problem eventually.
Also, given the Prius design, you shouldn't need to actually drive it to charge the 12V battery. If you just turn it on in "Run mode" ready to drive but leave it in Park, it should charge the 12V battery. There's no alternator, the ICE doesn't need to actually be running. The 12V system is powered through an inverter from the traction battery, and that battery gets recharged by the ICE as needed.
ztirffritz wrote:
[quote=Paul F.]
Stop overcomplicating it... replace the battery.
You have a dead battery... It's an EX-battery. It has shuffled off this mortal coil. It's pining for the fjords. It has EXPIRED.
If a good cable-check, cleaning, and tightening, doesn't do it... buy a new battery, install said battery.
That may or may not solve the underlying problem. If he's only driving a short distance/time then a new battery will likely result in the same problem eventually.