Lexus RX (RX 350L, RX450h) 2016-2025 Owners Manual: 12-volt battery

Location

RX450h

The 12-volt battery is located in the left-hand side of luggage compartment.

RX450hL

The 12-volt battery is located in the left-hand side of luggage compartment.

Removing the 12-volt battery cover

RX450h

1. Lift the deck board and attach the hook.

2. Remove the cover after removing the clips.

1. Press
2. Pull out

RX450hL

1. Remove the deck board and side auxiliary box cover.

2. Remove the 12-volt battery cover.

3. Remove the deck side trim cover.

Exterior

RX450h

Make sure that the 12-volt battery terminals are not corroded and that there are no loose connections, cracks, or loose clamps.

1. Terminals
2. Hold-down clamp

RX450hL

Make sure that the 12-volt battery terminals are not corroded and that there are no loose connections, cracks, or loose clamps.

1. Terminals
2. Hold-down clamp

Installing the 12-volt battery cover

RX450h

Install the 12-volt battery cover with the clips.

1. Push up center position
2. Insert
3. Press

RX450hL

1. Install the deck side trim cover.

2. Install the 12-volt battery cover.

■ Before recharging When recharging, the 12-volt battery produces hydrogen gas which is flammable and explosive. Therefore, observe the following precautions before recharging:

• If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the ground cable.
• Make sure the power switch on the charger is off when connecting and disconnecting the charger cables to the 12-volt battery.

■ After recharging/reconnecting the 12-volt battery

• The hybrid system may not start. Follow the procedure below to initialize the system.
  1. Shift the shift lever to P.
  2. Open and close any of the doors.
  3. Restart the hybrid system.
• Unlocking the doors using the smart access system with push-button start may not be possible immediately after reconnecting the 12-volt battery. If this happens, use the wireless remote control or the mechanical key to lock/unlock the doors.
• Start the hybrid system with the power switch in ACCESSORY mode. The hybrid system may not start with the power switch turned off. However, the hybrid system will operate normally from the second attempt.
• The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected, the vehicle will return the power switch mode to the status it was in before the 12-volt battery was disconnected. Make sure to turn off the power before disconnect the 12- volt battery. Take extra care when connecting the 12-volt battery if the power switch mode prior to discharge is unknown.

If the system will not start even after multiple attempts at all methods above, contact your Lexus dealer.

WARNING

■ Chemicals in the 12-volt battery The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce hydrogen gas which is flammable and explosive. To reduce the risk of death or serious injury, take the following precautions while working on or near the 12-volt battery:

• Do not cause sparks by touching the 12-volt battery terminals with tools.
• Do not smoke or light a match near the 12-volt battery.
• Avoid contact with eyes, skin and clothes.
• Never inhale or swallow electrolyte.
• Wear protective safety glasses when working near the 12-volt battery.
• Keep children away from the 12-volt battery.

■Where to safely charge the 12-volt battery Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in a garage or closed room where there is insufficient ventilation.

■ How to recharge the 12-volt battery Only perform a slow charge (5 A or less). The 12-volt battery may explode if charged at a quicker rate.

WARNING

■ Emergency measures regarding electrolyte

• If electrolyte gets in your eyes
  Flush your eyes with clean water for at least 15 minutes and get immediate medical attention. If possible, continue to apply water with a sponge or cloth while traveling to the nearest medical facility.
• If electrolyte gets on your skin
  Wash the affected area thoroughly. If you feel pain or burning, get medical attention immediately.
• If electrolyte gets on your clothes
  It can soak through clothing on to your skin. Immediately take off the clothing and follow the procedure above if necessary.
• If you accidentally swallow electrolyte
  Drink a large quantity of water or milk. Get emergency medical attention immediately.

■When disconnecting the 12-volt battery (RX450h)

Do not disconnect the negative (-) terminal on the body side as shown. The disconnected negative (-) terminal may touch the positive (+) terminal, which may cause a short and result in death or serious injury.

NOTICE

■When recharging the 12-volt battery Never recharge the 12-volt battery while the hybrid system is operating. Also, be sure all accessories are turned off.