Owner guide · Peoria Toyota · Peoria, IL
Toyota Prius 12-Volt Battery Guide
Which replacement 12-volt battery a Prius needs, where it is, how to jump start the car and how to check the voltage, from Toyota's Prius owner's manual, read November 10, 2026.
What 12-volt battery does a Toyota Prius use?
Toyota's Prius owner's manual calls for a 12-volt battery with the same case size as the previous one (LN1), a 20-hour rate capacity equivalent to 50Ah or greater and a CCA rating equivalent to 315A or greater: a ventilation type calcium battery with a handle. The battery is located in the right-hand side of the luggage compartment.
Prius 12-volt battery specifications
| Item | Owner's manual says |
|---|---|
| Location | Right-hand side of the luggage compartment |
| Replacement case size | Same as the previous battery (LN1) |
| 20-hour rate capacity (20HR) | Equivalent (50Ah) or greater |
| Performance rating (CCA) | Equivalent (315A) or greater |
| Battery type | Ventilation type calcium battery that conforms to European regulations, with a handle |
| Open voltage at 68°F (20°C) | 12.0 V or higher (turn the power switch to OFF and turn on the high beam headlights for 30 seconds) |
| Charging rate (slow charge) | 5 A max. |
| Jump starting point | Exclusive jump starting terminal under the hood (open the fuse box cover, then the terminal cover) |
From Toyota's Prius Owner's Manual (OM47F87U), pages 420, 505-507 and 520, read November 10, 2026. The manual does not print a model year on these pages; check the manual that came with your vehicle.
Where the Prius 12-volt battery is
The manual says the 12-volt battery is located in the right-hand side of the luggage compartment, under a cover. To remove the cover:
- On vehicles with a high deck, open the deck board.
- Hold the handle and pull it toward you so the 3 clips disengage.
- Take out the 12-volt battery cover. When installing, reverse the steps.
For jump starting you do not need to reach the battery itself: the manual uses an exclusive jump starting terminal under the hood, inside the fuse box cover.
How to jump start a Prius
If the 12-volt battery is discharged, the manual says you can start the hybrid system with jumper (or booster) cables and a second vehicle with a 12-volt battery, or call your Toyota dealer or a qualified repair shop. In short:
- Open the hood and the fuse box cover (push the two claws to release the lock, then lift the cover).
- Open the exclusive jump starting terminal cover.
- Connect a positive cable clamp to the exclusive jump starting terminal on your vehicle and the other end to the positive (+) terminal on the second vehicle. Connect a negative cable clamp to the negative (-) terminal on the second vehicle and the other end to the metallic point shown in the manual.
- Start the engine of the second vehicle, increase its engine speed slightly and hold it there for about 5 minutes to recharge your 12-volt battery.
- Keeping the second vehicle's engine speed up, start the hybrid system by turning the power switch to ON.
- Make sure the READY indicator comes on. If it does not, contact your Toyota dealer.
- Once the hybrid system has started, remove the cables in the exact reverse order from which they were connected, then close the terminal cover and reinstall the fuse box cover.
The manual says to have the vehicle inspected at your Toyota dealer as soon as possible once the hybrid system starts, that the hybrid system cannot be started by push-starting, and that the exclusive terminal cannot be used to jump start another vehicle. Make sure the cables do not become entangled in the cooling fan. To avoid igniting gas from the battery, the manual says to make sure each cable is on the correct terminal, keep the other end of the cable on the + terminal away from other parts and metal surfaces such as brackets or unpainted metal, never let the + and - clamps touch, and keep smoking, matches, lighters and open flame away from the battery. When removing the battery terminals, always remove the negative (-) terminal first.
Checking and charging the 12-volt battery
From the Prius owner's manual:
Look at the exterior
Make sure the terminals are not corroded and that there are no loose connections, cracks or loose clamps.
Indicator color (if equipped)
Blue means good condition. Red means charging is necessary; clear means replacement is necessary. For red or clear, the manual says to have the vehicle inspected by your Toyota dealer.
Check the voltage
12.0 V or higher at 68°F (20°C), measured after turning the power switch to OFF and the high beam headlights on for 30 seconds. If it is lower, charge the battery.
Slow charge, in the open
5 A max. Recharging produces flammable, explosive hydrogen gas, so charge in an open area, never in a garage or closed room without enough ventilation. Never recharge while the hybrid system is operating, and turn off all accessories. If the battery stays in the vehicle, disconnect the ground cable, and keep the charger switched off while connecting and disconnecting its cables.
Why it runs down
The battery discharges gradually even when the car is not used, and it recharges automatically while the hybrid system is operating. To help prevent discharge, the manual says to turn off the headlights and audio system while the hybrid system is off and switch off unnecessary electrical items in long, slow traffic.
After reconnecting
The smart key may not unlock the doors right away, so use the wireless remote control or the mechanical key. The manual says to start the hybrid system with the power switch in ACC, because it may not start with the power switch turned off; it will operate normally from the second attempt. Information stored in the ECU is cleared and some systems may need initialization.
From Toyota's Prius Owner's Manual (OM47F87U), pages 420-422, 506-507 and 520, read November 10, 2026. The manual also says to wear safety glasses, avoid sparks from tools touching the terminals, never smoke or light a match near the battery and keep children away from it.
Replacing a Prius 12-volt battery
Use a battery with the same case size as the one fitted (LN1). The manual says that if the sizes differ, the battery cannot be properly secured, and if the 20-hour rate capacity is low, the battery may discharge even when the car sits for only a short time, and the hybrid system may not be able to start.
After replacing, the exhaust hose and exhaust hole plug must be firmly attached to the exhaust hole of the new battery, with the hose firmly connected to the hole section of the vehicle. The manual warns that if they are not properly installed, hydrogen gas may leak into the vehicle interior and could ignite and explode.
Removing the 12-volt battery terminals clears information stored in the ECU, so the manual says to contact your Toyota dealer before removing them, and to always remove the negative (-) terminal first. For replacement details, it points owners to a Toyota dealer.
Peoria Toyota service hours
| Days | Hours |
|---|---|
| Mon-Fri | 7 a.m.-5:30 p.m. |
| Sat | 7 a.m.-12 p.m. |
| Sun | closed |
From Peoria Toyota's website, November 11, 2026. Holiday hours can differ.
Toyota Prius 12-volt battery FAQ
What size 12-volt battery does a Prius need?
Toyota's Prius owner's manual calls for a 12-volt battery with the same case size as the previous one (LN1), a 20-hour rate capacity (20HR) equivalent to 50Ah or greater and a performance rating (CCA) equivalent to 315A or greater. It should be a ventilation type calcium battery with a handle that conforms to European regulations.
Where is the 12-volt battery in a Prius?
The manual says it is located in the right-hand side of the luggage compartment. To reach it, open the deck board on vehicles with a high deck, then hold the 12-volt battery cover handle, pull it toward you to release the 3 clips and take the cover out.
How do I jump start a Prius?
With jumper cables and a second vehicle with a 12-volt battery: open the hood and the fuse box cover, open the exclusive jump starting terminal cover, and connect the positive cable to that terminal and the second vehicle's positive (+) terminal, then the negative cable to the second vehicle's negative (-) terminal and the metallic point the manual shows. Run the second vehicle's engine slightly faster for about 5 minutes, turn your power switch to ON, check that the READY indicator comes on, then remove the cables in the exact reverse order.
Can I use my Prius to jump start another car?
No. The manual says the exclusive jump starting terminal is for charging the 12-volt battery from another vehicle in an emergency and cannot be used to jump start another vehicle.
What voltage should a Prius 12-volt battery have?
The manual lists an open voltage of 12.0 V or higher at 68°F (20°C), measured after turning the power switch to OFF and turning on the high beam headlights for 30 seconds. If it is lower, the manual says to charge the battery; the slow charge rate is 5 A max.
Can a Prius be push-started?
No. The manual says the hybrid system cannot be started by push-starting.
Can Peoria Toyota replace my Prius 12-volt battery?
Yes. The manual says to contact your Toyota dealer for 12-volt battery replacement information. Our service team at 7401 N Allen Rd in Peoria can test the battery and fit the right one for your Prius. See the service hours above or schedule online.
Prius will not start or show READY?
Bring it to Peoria Toyota, 7401 N Allen Rd in Peoria. Our service team can test the 12-volt battery and replace it with the right one for your Prius.
Sources
Battery location, replacement requirements, jump start steps, charging and voltage figures are from Toyota's Prius owner's manual, read November 10, 2026. Your own owner's manual is the final word for your vehicle. Address and hours are from Peoria Toyota's own website. Photo is illustrative.
- Prius Owner's Manual (OM47F87U): 12-volt battery location, recharging, cover removal and checks (pp. 420-422), jump starting, discharge and replacement requirements (pp. 504-509), electrical system specifications (p. 520), Toyota, read November 10, 2026
- Address and service hours, Peoria Toyota, November 11, 2026
