2003 LEXUS LS430 air condition

OK:
Water valve lever changes in accordance with each display code.
NG: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
OK: Go to next step
2.INSPECT WATER VALVE SERVOMOTOR
a. Remove the water valve servomotor.
b. Connect the positive (+) lead from the battery to terminal 3 and negative (-) lead to terminal 1, then
check that the lever turns to the "OPEN" position smoothly.
c. Connect the positive (+) lead from the battery to terminal 3 and negative (-) lead to terminal 2, then
check that the lever turns to the "SHUT" position smoothly.
Fig. 134: Inspecting Water Valve Servomotor

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
7OPEN
8OPEN
9OPEN

NG: REPLACE WATER VALVE SERVOMOTOR
OK: Go to next step
3.CHECK HARNESS AND CONNECTOR (WATER VALVE SERVOMOTOR - AIR
CONDITIONING AMPLIFIER) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
WATER VALVE SERVOMOTOR - AIR CONDITIONING AMPLIFIER RESISTANCE
Tester connectionConditionSpecified condition
A37-15 (WVO) - W4-1 (OPEN)AlwaysBelow 1 ohms
A37-7 (WVS) - W4-2 (SHUT)AlwaysBelow 1 ohms
A37-14 (WVIG) - W4-3 (+)AlwaysBelow 1 ohms
A37-15 (WVO) - Body groundAlways10 kohms or higher
A37-7 (WVS) - Body groundAlways10 kohms or higher
A37-14 (WVIG) - Body groundAlways10 kohms or higher

Fig. 135: Checking Harness And Connector (Water Valve Servomotor - Air Conditioning

Amplifier)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
This circuit turns the servomotor and changes each damper position by receiving the signals from the A/C
amplifier assy. When the AUTO switch is on, the A/C amplifier changes the mode between "FACE", "BI-
LEVEL" and "FOOT" following the temperature setting.
WIRING DIAGRAM

c. Press the driver temperature up switch, and change to STEP operation.
d. Press the driver temperature up switch, and check the air flow mode by hand.
DISPLAY CODE - AIR FLOW POSITION
OK:
Air flow position changes in accordance with each display code.
NG: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
OK: Go to next step
2.INSPECT AIR VENT MODE CONTROL SERVOMOTOR
a. Remove the vent mode control servomotor.
b. Measure resistance according to the value (s) in the table below:
Standard: (Driver side)
AIR VENT MODE CONTROL SERVOMOTOR (DRIVER SIDE) RESISTANCE
Display codeAir flow position
0FACE
1FACE
2FACE
3FACE
4BI-LEVEL
5BI-LEVEL
6FOOT
7FOOT
8FOOT/DEF
9DEF
Tester connectionConditionSpecified condition
A44-1 (AODr1) -A44-4 (AODB)Always24.3 to 26.3 ohms
A44-2 (AODr2) -A44-4 (AODB)Always24.3 to 26.3 ohms
A44-5 (AODr3) -A44-4 (AODB)Always24.3 to 26.3
A44-6 (AODr4) -A44-4 (AODB)Always24.3 to 26.3

Fig. 137: Inspecting Air Vent Mode Control Servomotor (Driver'S Side)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Standard: (Passenger side)
AIR VENT MODE CONTROL SERVOMOTOR (PASSENGER SIDE) RESISTANCE
Tester connectionConditionSpecified condition
A45-1 (AOPa1) -A45-4 (AOPB)Always24.3 to 26.3 ohms
A45-2 (AOPa2) -A45-4 (AOPB)Always24.3 to 26.3 ohms
A45-5 (AOPa3) -A45-4 (AOPB)Always24.3 to 26.3 ohms
A45-1 (AOPa4) -A45-4 (AOPB)Always24.3 to 26.3 ohms

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE AIR OUTLET SERVOMOTOR
OK: Go to next step
3.CHECK HARNESS AND CONNECTOR (AIR OUTLET SERVOMOTOR - AIR
CONDITIONING AMPLIFIER) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard (Driver side):
AIR OUTLET SERVOMOTOR - AIR CONDITIONING AMPLIFIER RESISTANCE (DRIVER'S
SIDE)
Tester connectionConditionSpecified condition
A37-5 (AODr) -A44-6AlwaysBelow 1 ohms
A37-6 (AODr2) -A44-5AlwaysBelow 1 ohms
A37-12 (AODr3) -A44-2AlwaysBelow 1 ohms
A37-13 (AODr4) -A44-1AlwaysBelow 1 ohms
A37-22 (AODB) - A44-4AlwaysBelow 1 ohms
A37-5 (AODr1) - Body groundAlways10 kohms or higher
A37-6 (AODr2) - Body groundAlways10 kohms or higher
A37-12 (AODr3) - Body groundAlways10 kohms or higher
A37-13 (AODr4) - Body groundAlways10 kohms or higher
A37-22 (AODB) - Body groundAlways10 kohms or higher

Fig. 139: Checking Harness And Connector (Air Outlet Servomotor - Air Conditioning Amplifier)
(Driver'S Side)