L-SB-0022-21

July 22, 2021

Maintenance for HV and Auxiliary Batteries
Service
Category

General

Section

Pre-Delivery Service

Market USA

Applicability
YEAR(S)

MODEL(S)

2022

ES300H, LC500H, LS500H,
NX350H, NX450H+,
RX450H, UX250H

ADDITIONAL INFORMATION

Introduction

Hybrid vehicles are equipped with two types of batteries:



Hybrid Vehicle (HV) battery
Auxiliary (12V) battery

If the hybrid vehicle is put into storage, the State-Of-Charge (SOC) of its HV battery and auxiliary
battery will gradually decrease. To prevent the auxiliary battery from becoming discharged during
storage, proper maintenance is necessary.
Perform the following maintenance service for the HV battery and auxiliary battery.
NOTE
 BEFORE disconnecting the auxiliary battery, confirm the shift lever is in the “P” position. The shift lever
CANNOT be shifted from the “P” position with the auxiliary battery disconnected.
 Do NOT apply the parking brake. Ensure vehicles with electronic parking brakes do NOT engage and
the Auto function has been DISABLED (Refer to the Owner’s Manual for details).
 If the negative (–) terminal of the auxiliary battery is reconnected, even if the vehicle is powered ON
(Ready ON), the hybrid system may NOT start. In this case, depress the brake pedal and press the
Power button to start the hybrid system (the Ready light is ON). If the hybrid system still does NOT
start (the Ready light is OFF), refer to the applicable model and model year Repair Manual.

© 2021 Lexus, a division of Toyota Motor Sales, USA

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L-SB-0022-21

July 22, 2021

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Maintenance for HV and Auxiliary Batteries
Maintenance Items
CONDITION*

MAINTENANCE OPERATION

Fully charge the auxiliary battery. Fast charge is NOT
recommended on the 12V battery in order to prevent battery
damage. Deliver the vehicle to the customer AFTER it has fully
charged to 12.6V or more.

Before Delivery

To Store for 30 Days or More

Disconnect the negative (–) terminal of the auxiliary battery to
prevent the SOC from decreasing during storage due to
parasitic current.

Periodical Battery Charging:


Within 45 days AFTER loading
on ship and then every
2 months.**



Upon arrival at the dealership
and then every 2 months.***

Keep the hybrid system ON for 30 minutes with the
transmission in the “P” position (in order to charge the HV
battery and the auxiliary battery).

*The condition also corresponds with the section titles within this bulletin.
**BEFORE arrival at the dealership.
***AFTER arrival at the dealership.

Warranty Information
OP CODE

DESCRIPTION

TIME

OFP

T1

T2

N/A

Not Applicable to Warranty

–

–

–

–

Required Tools & Equipment
SPECIAL SERVICE TOOLS (SST)

PART NUMBER

QTY

Battery Diagnostic Tool*

DCA-8000P T

1

*Essential SST.

NOTE
 The DCA-8000 battery diagnostic tool (P/N DCA-8000P T) supersedes the GR8 battery diagnostic
station (P/N 00002-MCGR8).
 Additional SSTs may be ordered by calling 1-800-933-8335.

Before Delivery

1. BEFORE charging the auxiliary battery, turn OFF ALL lights, accessories, and the
hybrid system.

© 2021 Lexus, a division of Toyota Motor Sales, USA

L-SB-0022-21

July 22, 2021

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Maintenance for HV and Auxiliary Batteries
Before Delivery (continued)

2. Check the battery SOC.


If the battery voltage is LESS THAN 12.6V, continue to step 3.



If the battery voltage is 12.6V or MORE, replace the positive (+) terminal cover, install the
battery cover (if applicable), and close the luggage compartment/hood.
NOTE
 If measuring the voltage with the negative (–) terminal connected, turn OFF the Power
button and turn ON the high beams for 20 – 30 seconds. This will remove the surface
charge from the battery.
 If the engine has been running before measuring the voltage, wait 20 minutes or more after
the engine stops. This removes the surface charge.
 For details on how to use the battery diagnostic station, refer to the DCA-8000 Instruction Manual
located at TIS – Diagnostics – Tools & Equipment – Battery Diagnostics.


3. Test the auxiliary battery using the
DCA-8000 battery diagnostic tool
Advanced Battery Test mode.

Figure 1. DCA-8000 Battery Diagnostic Tool

If charging is required, the DCA-8000
battery diagnostic tool will automatically start
to charge.
A. Connect the red charger clamp to the
positive (+) terminal and the black
charger clamp to the negative
(–) terminal.
B. Plug the charger into a grounded 110V
outlet and press the power button.
C. Once the DCA-8000 battery diagnostic
tool is properly turned ON, perform an
Advanced Battery Test. The DCA-8000
battery diagnostic tool will indicate
results when complete. If the battery
tests bad “Replace Battery,” replace the
auxiliary battery.

CAUTION
 Charge in a well-ventilated area.
 Do NOT allow sparks OR fire near the auxiliary battery.
NOTE
If the auxiliary battery was stored at 32°F (0°C) or below, charge the auxiliary battery in a room
above 32°F (0°C).
© 2021 Lexus, a division of Toyota Motor Sales, USA

L-SB-0022-21

July 22, 2021

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Maintenance for HV and Auxiliary Batteries
Before Delivery (continued)

4. If the DCA-8000 battery diagnostic tool is NOT available, you may charge the auxiliary battery
by cycling the vehicle to Ready ON.


Run time will vary depending on the battery SOC.



If this method is used, you MUST confirm that the battery is charged to 12.8V using
a DVOM.

To Store for 30 Days or More
Disconnect the Negative (–) Terminal

1. Turn OFF ALL lights, accessories, and the hybrid system.
2. Disconnect the negative (–) terminal.

Figure 2.

NOTE
When it is necessary to move the vehicle,
reconnect the negative (–) terminal.

1

3. When removing the vehicle from storage,
connect the negative (–) terminal.
Please refer to applicable Repair Manual for
torque specifications.
NOTE
AFTER recharging the auxiliary battery, the
hybrid system may NOT start. Follow the
procedure below to initialize the system.

1

Negative (–) Terminal

1. Put the shift lever in the “P” position.
2. Open and close ANY of the doors.
3. Restart the hybrid system.
Periodical Battery Charging
Cycle the Vehicle to Ready ON
NOTE
 When the remaining capacity of the HV battery is low, the gasoline engine automatically starts and the
HV battery is charged. The auxiliary battery is also charged by the HV battery regardless of the gasoline
engine operation.
 Be sure to reconnect the negative (–) terminal of the auxiliary battery BEFORE performing
this procedure.
When
remaining
capacity
the HV battery
is low, the
gasolinehose
engine
1. Park
thethe
vehicle
in open
air orofconnect
the exhaust
extraction
to automatically
the exhaust starts
pipe. and the
HV battery is charged. The 12V auxiliary battery is also charged by the HV battery regardless of the

2. Apply
the parking
brake.
gasoline
engine operation.

 Make sure to reconnect the negative (–) terminal of the auxiliary battery BEFORE performing
© 2021 Lexus, a division of Toyota Motor Sales, USA
this procedure.

L-SB-0022-21

July 22, 2021

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Maintenance for HV and Auxiliary Batteries
Periodical Battery Charging (continued)
Cycle the Vehicle to Ready ON (continued)

3. With the brake pedal depressed, push the
Power button and check that the Ready light
in the meter illuminates when the hybrid
system starts (the Ready light is ON).

Figure 3.

4. Turn OFF ALL lights and accessories.
5. Check that the shift lever is in the “P” position.
6. Keep the Ready light ON and charge the HV battery for 30 minutes.
NOTE
 If the amount of charging energy is small, the display may NOT indicate the energy flow.
 Ensure there is a sufficient amount of fuel for the vehicle to run for 30 minutes.

© 2021 Lexus, a division of Toyota Motor Sales, USA