Prius Prime - 12V Charging System

There is a sub DC-DC converter, but it’s not clear whether it can recharge an auxiliary (12-volt) battery that has already been discharged, or just keep the battery from discharging further.

Use a battery maintainer, sold at auto parts stores for less than $100. This device connects to a 120-volt wall outlet and to the positive (+) and negative (–) terminals of the auxiliary battery under the hood. It will recharge the auxiliary battery, if the battery’s condition allows, and then can be left connected to maintain its charge.

You’ll also need to maintain the state of charge of the HV battery, of course. You could use your external charger (EVSE), or as an alternative (recommended by Toyota for new cars in stock at dealers), run the hybrid system for 30 minutes at least once every two months, with the transaxle in P⃣ and the car parked in a place where it’s safe for the gasoline engine to run as needed.

I’m not sure I’d go to a dealer for this problem, since there’s no warranty coverage, nor anything that requires a dealer’s special equipment or expertise. If the auxiliary (12-volt) battery just needs recharging, I’d suggest doing that at home, since you’ll need the same equipment to keep it charged. If it has to be replaced, you could do it yourself, or if you prefer, many stores that sell 12-volt automotive batteries will also install them at no charge or for a nominal fee.

 

Weird, my browser (Firefox) shows a "combining enclosing keycap" not combined with the P ... it's further to the right, covering the first part of 'and'. And it's too high, so it covers the bottoms of the letters rather than enclosing them. Something wrong with the metrics in the font, maybe?

 

Thanks, i would get the commerically available battery charger and maintainer from costco. Duracell brand approx $50
Appreciate your suggestion and i will post here my response once i get to use it. Thanks