TECHNICAL INSTRUCTIONS
21TC02
IMPROPER PROGRAMING IN A 12V BATTERY MANAGEMENT SYSTEM
CERTAIN 2021 MODEL YEAR SUPRA VEHICLES

The repair quality of covered vehicles is extremely important to Toyota. All dealership
technicians performing this recall are required to successfully complete the most current version
of the E-Learning course “Safety Recall and Service Campaign Essentials”. To ensure that all
vehicles have the repair performed correctly; technicians performing this recall repair are
required to currently have completed all of the following courses:
•

TIN519B – GR Supra New Model Technical Introduction

Always check which technicians can perform the repair by logging on to
https://www.uotdealerreports.com. It is the dealership’s responsibility to select technicians with
the above certification level or greater to perform this repair. Carefully review your resources, the
technician skill level, and ability before assigning technicians to this repair. It is important to
consider technician days off and vacation schedules to ensure there are properly trained
technicians available to perform this repair at all times.

I.

OPERATION FLOW CHART

Verify Vehicle Eligibility
1. Confirm vehicle VIN matches the R.O.
2. Check the TIS Vehicle Inquiry System

Not Covered

No further action required

Covered

Replace 12-volt sub-battery

Register 12-volt sub-battery

Campaign completed, return
the vehicle to the customer

II.

IDENTIFICATION OF AFFECTED VEHICLES

1. CHECK VEHICLE FOR CAMPAIGN ELIGIBILITY
a. Compare the vehicle’s VIN to the VIN listed on the Repair Order to ensure they match.
b. Check the TIS Vehicle Inquiry System to confirm the VIN is involved in this Campaign, and
that it has not already been completed.
Note: TMNA warranty will not reimburse dealers for repairs completed on vehicles that are not
affected or were previously completed, even by another dealer.
III. BACKGROUND
Due to a software error in the battery management system of the 12V battery located under the
vehicle’s hood, the engine auto Stop/Start functionality could become deactivated.

2

IV. PREPARATION
1. PARTS

Part No.
28800-WAA13
90118-WA243
90118-WA253

Description
BATTERY
HEXAGON SCREW WITH FLANGE
HEXAGON SCREW WITH FLANGE

Quantity
1
4
4

2. TOOLS & EQUIPMENT

o
o
o
o
o
o
o

Techstream ADVi
Supra Diagnostic Cable (01018-00118)
Torque Wrench Angle Gauge (SST 09900-WA010 or equivalent)
Wiper Arm Pulling Tool (SST 09800-WA020 or equivalent)
DCA-8000 Battery Charger (DCA-8000P T)
Standard Hand Tools
Torque Wrench

3. BATTERY RECYCLE PROCEDURE

Refer to page 28 for instructions on how to properly recycle the 12-volt lithium ion battery
replaced by this Special Service Campaign
V. WORK PROCEDURE TABLE OF CONTENTS
COMPONENTS ·································································································
DISCONNECT NEGATIVE CABLE FROM NO. 2 BATTERY ·····································
DISCONNECT NEGATIVE CABLE FROM MAIN BATTERY ·····································
REMOVE NO. 2 BATTERY ·················································································
INSTALL NEW NO. 2 BATTERY···········································································
REASSEMBLE VEHICLE····················································································
REGISTER NEW NO. 2 BATTERY ········································································
RECYCLING INSTRUCTIONS – BATTERY (28800-WAA13) ·····································

SECTION VI
SECTION VlI
SECTION VIII
SECTION IX
SECTION X
SECTION XI
SECTION XII
SECTION XIII

3

VI.

COMPONENTS

4

5

VII.

DISCONNECT NEGATIVE CABLE FROM NO. 2 BATTERY (SUB-BATTERY)
1.

REMOVE FRONT WIPER ARMS
a.

Remove the front wiper arm head cap.

b.

Using a socket wrench 16mm, remove nut.

a.

Using special tool (09800-WA020) or equivalent,
pull off the front wiper arm and blade assembly
LH.
Repeat this procedure for the RH wiper arm.

b.

2.

REMOVE COWL VENT COVER LH
Disengage the lock.
Remove cowl vent cover LH.

6

3.

REMOVE COWL VENT COVER RH
Type B

Type A

Disconnect the connector and washer nozzle and hose assembly from the cowl vent
cover RH.
Disengage the lock.
Remove the cowl vent cover RH.
4.

REMOVE FRONT FENDER TO COWL SIDE SEAL LH
Remove the clips.
Remove front fender to cowl side seal LH.

5.

REMOVE FRONT FENDER TO COWL SIDE SEAL RH
Disengage the claws.
Disengage the guide to remove the water guard
plate

7

6.

REMOVE COWL TOP VENTILATOR LOUVER SUB-ASSEMBLY
Disengage the claws.
Disconnect the cowl top ventilator louver subassembly.

Pull the cowl top ventilator louver sub-assembly
upward out of the claw
beginning on the
side

7.

REMOVE UPPER FRONT SUSPENSION CENTER BRACE
NOTICE: Driving without upper front suspension center brace is not permissible.

Remove bolts
Remove the upper front suspension center brace

8

8.

DISCONNECT NEGATIVE CABLE FROM NO. 2 BATTERY (SUB-BATTERY)
NOTICE:
Check that the START-STOP button (engine switch) is off.
HINT:
Pressing and holding the AUDIO button changes the power source mode to IG OFF.

VIII.

a.

Unfasten nut.

b.

Disconnect negative cable

DISCONNECT NEGATIVE CABLE FROM MAIN BATTERY (TRUNK BATTERY)
1.

REMOVE PACKAGE TRAY TRIM PANEL ASSEMBLY
a.

Move the RH front seat to the foremost position.
Detach the retaining straps
Detach the rear mountings
Detach the front guides
Detach the front guides to the rear

b.

Fold the package tray trim panel assembly
together and remove

9

2.

REMOVE DECK BOARD ASSEMBLY
a.
b.

c.

3.

Slightly lift the deck board assembly on the right
side with a suitable tool.
Slide the left edge of the deck board assembly
into the recess in the direction of the arrow of the
deck board assembly.

Slide the left edge of the deck board assembly
into the recess in the direction of the arrow of the
deck board assembly.

DISCONNECT NEGATIVE CABLE FROM MAIN BATTERY (TRUNK BATTERY)
a.

Unfasten nut.

b.

Disconnect negative cable

10

IX.

REMOVE NO. 2 BATTERY (SUB-BATTERY)
1.

REMOVE NO. 2 BATTERY (SUB-BATTERY)
Loosen the latch mechanisms
a.

Remove connector cover

b.

Loosen nut

c.

Remove battery rollover protection bracket

d.

Unlock connector (5) and disconnect

Loosen nut
Pull off No.4 engine room wire (2) from the
battery terminal and secure at side
Remove No.2 battery

Remove bleeding angular piece
Remember to recycle the old battery following
the instructions on page 28 of this document.

11

X. INSTALL NEW NO. 2 BATTERY (SUB-BATTERY)
1.

2.

INSTALL BLEEDING ANGULAR PIECE

a.

Install bleeding angular piece to the NEW No. 2
Battery.

a.

Install the NEW No.2 battery.

b.