90069-08007

O-ring (External Dimension:
~15.6 mm (0.614 in.))

1

90099-14121

O-ring (External Dimension:
~18.2 mm (0.717 in.))

1

87106-28170

Damper Servo Sub-assembly
(For Rear Air Mix)

1

16418-15520

Packing
(for Radiator Drain Cock)

1

90068-14011

O-ring (External Dimension:
~10.3 mm (0.406 in.))

1

90069-08007

O-ring (External Dimension:
~15.6 mm (0.614 in.))

1

90189-06065

Grommet

2

87106-60340

Damper Servo
Sub-assembly (P)

1

90068-14011

O-ring (External Dimension:
~10.3 mm (0.406 in.))

1

90069-08007

O-ring (External Dimension:
~15.6 mm (0.614 in.))

1

87106-58030

Damper Servo Sub-assembly
(for Rear Mode)

1

87106-60280

Damper Servo Sub-assembly
(for Rear Air Mix No. 2)

1

—

W/Cooler Box

[11] Air Outlet Servo (Rr D)
[12] Rear Air Mix Servo (P)

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Page 12 of 71

HVAC Servo Motor Malfunction
Required Tools & Equipment
SPECIAL SERVICE TOOLS (SST)

PART NUMBER

QTY

Plastic Pry Tool Kit*

00002-06020-02

1

DCA-8000 Battery Diagnostic Tool*

DCA-8000P T

1

*Essential SST.

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

REQUIRED EQUIPMENT

SUPPLIER

PART NUMBER

Techstream ADVi*

TSADVUNIT

Techstream 2.0

TS2UNIT
ADE

Techstream Lite
Techstream Lite (Green Cable)

TSLITEPDLR01
TSLP2DLR01

*Essential SST.

NOTE
 Only ONE of the Techstream units listed above is required.
 Software version 15.30.027 or later is required.
 Additional Techstream units may be ordered by calling Approved Dealer Equipment (ADE)
at 1-800-368-6787.

Calibration Information
CALIBRATION ID
MODEL

MODEL YEAR

2016

PREVIOUS

NEW

8865060Q2002

8865060V8001

8865060Q2201

LX570
2017

8865060Q1001
8865060Q2101

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QTY

© 2019 Lexus, a division of Toyota Motor Sales, USA

8865060W0001

1

Page 13 of 71

HVAC Servo Motor Malfunction
Confirmation Procedure

1. Confirm one or more of the following conditions is present:


Uneven temperature or air flow between the vents.



Little or no air flow from the vent(s).



Improper MODE control function.

Does the vehicle exhibit ANY of the conditions listed above?


YES — Go to the Flash Reprogramming Procedure.



NO — Continue to step 2.

2. Using Techstream, check for the following stored DTCs:


B1441 – Air Mix Damper Control Servo Motor Circuit (Passenger Side).



B1442 – Air Inlet Damper Control Servo Motor Circuit.



B1443 – Air Outlet Damper Control Servo Motor Circuit.



B1445 – Passenger Side Cool Air Bypass Damper Control.



B1446 – Air Mix Damper Control Servo Motor Circuit (Driver Side).



B1447 – Rear Air Mix Damper Control Servo Motor Circuit (Driver Side).



B1448 – Passenger Side Face Servo Motor Circuit.



B1449 – Rear Air Outlet Damper Control Servo Motor Circuit.



B1457 – Driver Side Air Outlet Damper Control Servo Motor Circuit.



B1458 – Passenger Side Air Outlet Damper Control Servo Motor Circuit.



B1486 – Driver Side Air Outlet Damper Control Servo Motor Circuit.



B1488 – Rear Air Mix Damper Control Servo Motor Circuit (Front Passenger).

3. Are ANY of the DTCs listed above present?


YES — Continue to the Flash Reprogramming Procedure.



NO — This bulletin does NOT apply. Continue diagnosis using the applicable
Repair Manual.

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Page 14 of 71

HVAC Servo Motor Malfunction
Flash Reprogramming Procedure

1. Flash Reprogram the air conditioning amplifier assembly.
NOTE
The air conditioning amplifier flash reprogram is only performed one time if the air conditioning
amplifier has NOT been flash reprogrammed previously.

Follow the procedure outlined in Service Bulletin L-SB-0001-18, Techstream ECU Flash
Reprogramming Procedure, and flash reprogram the air conditioning amplifier with the NEW
calibration file update.
NOTE
The battery diagnostic tool MUST be used in Power Supply Mode to maintain battery voltage above
11.4V while flash reprogramming the air conditioning amplifier.

NOTICE
 Damage to the air conditioning amplifier may occur if the correct battery charge mode
setting is NOT used.
 Power Supply Mode is used to maintain battery voltage at 13.5V while
flash reprogramming.
 For details on how to use the battery diagnostic tool, refer to the
DCA-8000 Battery Diagnostic Tool Instruction Manual located on TIS - Diagnostics – Tools
& Equipment – Battery Diagnostics.

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Page 15 of 71

HVAC Servo Motor Malfunction
Servo Cleaning Operation Procedure

1. Clean the servos using the AC damper servo operation check tool.
A. Continue with the battery diagnostic tool connected using the
“Power Supply Mode” ONLY.
B. Confirm flash reprograming of the air
conditioning amplifier is complete,
otherwise the AC damper servo
operation check tool will show the
corresponding error message.

Figure 1.

NOTE
The AC damper servo operation check
tool will ONLY function correctly with the
NEW calibration file update.

C. BEFORE using the AC damper servo operation check tool, manually set the front and rear
air conditioning to the following settings:


MODE – Face



Temperature – Max Cold



Air Inlet – Fresh

Download the AC damper servo operation check tool onto the Techstream desktop.
Select the following link to download the AC damper servo operation check tool
to Techstream:
AC damper servo operation check tool download.
NOTE
Depending on browser and settings used, the file may not automatically save to the
Techstream desktop. If this is the case, locate the downloaded file and save it to the
Techstream desktop.

E. Confirm the ignition is in the IG-ON position and the Techstream unit is connected to the
DLC3 connector.
F. Confirm NO other programs on the Techstream unit are currently communicating
with the vehicle.
G. Double-click on the AC damper servo operation check tool from the Techstream desktop.

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Page 16 of 71

HVAC Servo Motor Malfunction
Servo Cleaning Operation Procedure (continued)

H. Click on NEXT to start the AC damper
servo operation check tool and the
progress bar will show. It will take
between 8 – 14 minutes to complete the
cleaning process depending on the
condition of the servos. The completion
rate of the progress bar will show
between 50% – 100%.

Figure 2.

NOTE
If the connection between Techstream
and the vehicle is interrupted during the
cleaning process, the error message in
Figure 2 will also display. To reconnect,
turn OFF the Techstream unit and
disconnect it from the DLC3 connector,
reconnect Techstream and confirm
connections, and turn ON the
Techstream unit and restart the
cleaning process.

I.

When the cleaning process is complete, the DTC check result screen shown on the next
page will be displayed. If ANY DTC is output, the servo related to it will require replacement.
(Reference the Servo Location Guide (page 19) for the servo motor location.)
NOTE
If DTCs B1497 or B149A are output, this bulletin does NOT apply. The communication from the
air conditioning amplifier to each servo has an error or a communication interruption.
Complete substeps I and J, and continue diagnosis using the applicable Repair Manual.

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Page 17 of 71

HVAC Servo Motor Malfunction
Servo Cleaning Operation Procedure (continued)

Are ANY DTCs output?


YES — Check DTC and Servo
Location Guide and replace the
appropriate servo according to
the displayed DTC (Figure 3).



NO — Complete substeps J – K to
complete the repair and return
the vehicle to the
customer (Figure 4).

Figure 3.

Figure 4.

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Page 18 of 71

HVAC Servo Motor Malfunction
Servo Cleaning Operation Procedure (continued)

J. Take a screen shot of the VIN displayed on the Techstream System Selection Menu
overlaid with the AC damper servo operation check tool results showing the DTCs. Retain
the screen shot as per Toyota Warranty Policies and Procedures with the repair order.
Figure 5.

K. The Servo Cleaning Operation is complete. Cycle the ignition to the IG-OFF position and
select Exit.

L. Turn OFF and disconnect the battery diagnostic tool.

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Page 19 of 71

HVAC Servo Motor Malfunction
Damper Servo Sub-assembly Replacement Procedure
NOTE
The servo replacement procedure (and surrounding parts to remove) varies depending on the servo being
replaced. Perform the replacement work according to the Servo Location Guide.
Servo Location Guide
Required Removal Work for Replacement of Each Servo
Figure 6. Servo Replacement
on Vehicle

Figure 7. Servos Replaced From Air Conditioning
Units Removed From Vehicle
C

A

z

z

1

z

D

z

1

z

B

z

2

2




A

Group A

B

Group B

1

Instrument Panel Safety Pad Assembly

2

Front Quarter Trim Panel Assembly, LH

z

C

Group C

D

Group D

1

Air Conditioning Unit

2

Rear Cooling Unit Assembly

z

Groups A and B servo replacement:
Servo replacement takes place on the vehicle.
Groups C and D servo replacement:
To access the servos, servo replacement requires removal of the air conditioning unit and the
rear cooling unit assembly from the vehicle.
If multiple servos need to be replaced that require groups C or D procedures, performing
procedures for groups A and B will NOT be necessary.

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© 2019 Lexus, a division of Toyota Motor Sales, USA

Page 20 of 71

HVAC Servo Motor Malfunction
Damper Servo Sub-assembly Replacement Procedure (continued)
Servo Location Guide (continued)
NO.

DTC

[1]