L-SB-0107-17

Rev2

January 30, 2017

Maintenance for HV and Auxiliary Batteries
Service
Category

General

Section

Maintenance

Market USA

Applicability
YEAR(S)

MODEL(S)

2018 - 2019

ES300H, LC500H, LS500H,
NX300H, RX450H

2018

GS450H

2019

UX250H

ADDITIONAL INFORMATION

REVISION NOTICE
November 26, 2018 Rev2:
 Applicability has been updated to include 2019 model year UX250h vehicles.
May 10, 2018 Rev1:
 Applicability has been updated to include 2019 model year vehicles.
Any previous printed versions of this bulletin should be discarded.

Introduction

Hybrid vehicles are equipped with two types of batteries:


Hybrid Vehicle (HV) battery



Auxiliary (12V) battery

If the 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 and
apply the parking brake completely. The shift lever cannot be shifted from the “P” position with the
auxiliary battery disconnected.
 If the negative (–) terminal of the auxiliary battery is reconnected, even if the power switch is selected
to the Start mode, the hybrid system may not start. In this case, push the Power switch to select Start
again 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 Repair Manual.
 If the vehicle is equipped with VGRS, the system must be initialized after the auxiliary battery
has been reconnected. Refer to the applicable Service Bulletin for instructions.

© 2018 Lexus, a division of Toyota Motor Sales, USA

Page 1 of 6

L-SB-0107-17

Rev2

January 30, 2017

Page 2 of 6

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 is fully
charged to 12.6V.)

Before Delivery

To Store for 30 Days or More

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

Just After Unloading and
Every 2 Months

*The condition also corresponds with the section titles in this Service Bulletin.

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

GR8 Battery Diagnostic Station*

00002-MCGR8

1

* Essential SST.

NOTE
Additional SSTs may be ordered by calling 1-800-933-8335.

Before Delivery

1. BEFORE charging the auxiliary battery, turn OFF ALL lights and accessories.
2. Locate the auxiliary battery.

© 2018 Lexus, a division of Toyota Motor Sales, USA

L-SB-0107-17

Rev2

January 30, 2017

Page 3 of 6

Maintenance for HV and Auxiliary Batteries
Before Delivery (continued)

3. Remove the positive (+) terminal cover.

Figure 1.
1

1

Positive (+) Terminal Cover

4. Check the battery SOC.


If the battery voltage is LESS THAN 12.6V, continue to step 5.



If the battery voltage is 12.6V or MORE, replace the positive (+) terminal, close the battery
cover, install the luggage compartment floor mat, and close the trunk.
CAUTION
If measuring the voltage with the negative (–) terminal connected, verify IG/OFF, and turn the
headlights ON for 60 seconds or more. This will remove the surface charge.

5.

Test the auxiliary battery using the GR8
Battery Diagnostic Station.
If charging is required, the GR8 will
automatically start to charge.
A. Connect the red charger clamp to the
positive (+) battery terminal and the
black charger clamp to the negative (–)
battery terminal.

Figure 2. GR8 Battery Diagnostic Station

B. Plug the charger into a grounded

110V outlet and flip the power switch to
the ON position.

© 2018 Lexus, a division of Toyota Motor Sales, USA

L-SB-0107-17

Rev2

January 30, 2017

Page 4 of 6

Maintenance for HV and Auxiliary Batteries
Before Delivery (continued)

C. Once the charger is properly turned ON, perform a diagnostic charge (make sure to select
the appropriate vehicle model). The GR8 Battery Diagnostic Station will indicate results
when complete. If the battery tests bad (“Replace Battery”), replace the auxiliary battery.
NOTE
 If the vehicle model is NOT listed in the model list, charge by battery stock code. To charge by
stock code, refer to the Lexus Battery Stock Number Chart located on TIS – Diagnostics –
Tools & Equipment – Battery Diagnostics.
 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).

CAUTION
 Charge in a well-ventilated area.
 Do NOT allow sparks or fire near the auxiliary battery.

6. If the GR8 Battery Diagnostic Station is NOT available, you may charge the 12V battery by
turning the vehicle to Ready ON.
 Run time will vary depending on the 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 and accessories.
2. Disconnect the negative (–) terminal.

Figure 3.

NOTE
1

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

1

Negative (–) Terminal Cover

© 2018 Lexus, a division of Toyota Motor Sales, USA

L-SB-0107-17

Rev2

January 30, 2017

Page 5 of 6

Maintenance for HV and Auxiliary Batteries
Every Two Months
Cycle 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.
 Make sure to reconnect the negative (–) terminal of the auxiliary battery BEFORE performing
this procedure.

1. Park the vehicle in open air, or connect the exhaust extraction hose to the exhaust pipe.
2. Apply the parking brake.
3. With the brake pedal depressed, push the
Power switch and check that the Ready light
in the meter illuminates when the hybrid
system starts (the Ready light is ON).

Figure 4.

4. Turn OFF ALL lights and accessories.
5. Check that the shift lever is in the “P” position.

© 2018 Lexus, a division of Toyota Motor Sales, USA

L-SB-0107-17

Rev2

January 30, 2017

Page 6 of 6

Maintenance for HV and Auxiliary Batteries
Every Two Months (continued)
Cycle Vehicle to Ready ON (continued):

6. Keep the Ready light ON and charge the HV
battery for 30 minutes.

Figure 5.

1

NOTE
 If the amount of charging energy is
small, the display may NOT indicate
the energy flow.

2

3

 Ensure there is a sufficient amount of
fuel for the vehicle to run for 30 minutes.
4

6

1

Energy Monitor

2

Engine

3

Battery

4

Electric Motor

5

Past Record

6

Consumption

© 2018 Lexus, a division of Toyota Motor Sales, USA

5