T-SB-0014-24

T-SB-0014-24
March 12, 2024
Delayed and/or Reduced Heat From the HVAC System,
After Hot Restart, Prior to the Internal Combustion
Engine Starting
Service
Category
Vehicle Interior
Section
Heating/Air Conditioning
Market USA
Applicability
YEAR(S)
MODEL(S)
ADDITIONAL INFORMATION
2023
Crown
VDS(s): AFAAF
Engine(s): T24
Transmission(s): 6AT-F
Introduction
Some 2023 model year Crown vehicles may exhibit a delay and/or reduction in output of warm air
from the HVAC system while the vehicle engine is at normal operating temperatures (over 170°F).
This condition usually occurs immediately after a hot restart, while the vehicle is in Ready ON, but
before the internal combustion engine starts. The Engine Control Module (ECM) (SAE term:
Powertrain Control Module/PCM) logic has been modified to reduce the possibility of this
condition. Follow the Repair Procedure in this bulletin to address this condition.
Warranty Information
OP CODE
DESCRIPTION
TIME
OFP
T1
T2
AC2401
Reprogram the ECM (PCM)
0.7
89661-#####*
87
74
*Warranty claim MUST be submitted with the correct 10-digit OFP. Choose the correct OFP for the vehicle being
repaired by searching for the parts in the Electronic Parts Catalog using the VIN filter.
APPLICABLE WARRANTY
 This repair is covered under the Toyota Federal Emission Warranty. This warranty is in effect
for 96 months or 80,000 miles, whichever occurs first, from the vehicle’s in-service date.
 Warranty application is limited to occurrence of the specified condition described in
this bulletin.
© 2024 Toyota Motor Sales, USA
Page 1 of 3
T-SB-0014-24
March 12, 2024
Page 2 of 3
Delayed and/or Reduced Heat From the HVAC System, After Hot Restart, Prior
to the Internal Combustion Engine Starting
Parts Information
PART NUMBER
PART NAME
QTY
Computer, Engine Control
–
89661-4D650
89661-3AF60
NOTE
The ECM (PCM) should NOT be replaced as part of the Repair Procedure.
Required Tools & Equipment
SPECIAL SERVICE TOOLS (SST)
PART NUMBER
QTY
Battery Diagnostic Tool*
DCA-8000P T
1
*Essential SST.
NOTE
Additional SSTs may be ordered by calling 1-800-933-8335.
REQUIRED EQUIPMENT
SUPPLIER
Techstream ADVI*
PART NUMBER
QTY
TSADVUNIT
Techstream 2.0
TS2UNIT
ADE
1
Techstream Lite
TSLITEPDLR01
Techstream Lite (Green Cable)
TSLP2DLR01
*Essential SST.
NOTE
 Only ONE of the Techstream units listed above is required.
 GTS+ software version 2023.04.003.02 or later is required.
 Additional Techstream units may be ordered by calling Approved Dealer Equipment (ADE)
at 1-800-368-6787.
 Use Techstream or an approved J2534 interface to perform flash reprogramming updates.
Visit techinfo.toyota.com for more information regarding J2534 reprogramming.
© 2024 Toyota Motor Sales, USA
T-SB-0014-24
March 12, 2024
Page 3 of 3
Delayed and/or Reduced Heat From the HVAC System, After Hot Restart, Prior
to the Internal Combustion Engine Starting
Calibration Information
CALIBRATION ID
MODEL
Crown
ENGINE
T24A-FTS
PREVIOUS
NEW
8A2223009000
8A2223009100
8A2223009200
8A2223009300
8A2223009400
Repair Procedure
1. Confirm the condition exists.
Does the vehicle exhibit a delay and/or reduction in output of warm air from the HVAC system
while the vehicle engine is at normal operating temperatures (over 170°F)? This condition may
occur immediately after a hot restart, while the vehicle is in Ready ON, but before the internal
combustion engine starts.

YES — Continue to step 2.

NO — This bulletin does NOT apply. Continue diagnosis using the applicable
Repair Manual.
2. Use GTS+ to confirm if the ECM (PCM) calibration has been updated.
Is the calibration ID listed in GTS+ the latest ECM (PCM) calibration?

YES — This bulletin does NOT apply. Continue diagnosis using the applicable
Repair Manual.

NO — Continue to step 3.
3. Flash reprogram the ECM (PCM).
NOTE
 The battery diagnostic tool MUST be used in Power Supply Mode to maintain battery voltage at
13.5V while flash reprogramming the vehicle.
 For details on how to use the battery diagnostic tool, refer to the DCA-8000 Instruction Manual
located at TIS – Diagnostics – Tools & Equipment – Battery Diagnostics.
Follow the procedures outlined in T-SB-0107-20 GTS+ ECU Flash Reprogramming With
Security Signature and flash the ECM (PCM) with the NEW calibration file update.
4. Confirm the condition no longer exists.
© 2024 Toyota Motor Sales, USA