2003 LEXUS LS430 air conditioning

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

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)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Standard (Passenger side):
AIR OUTLET SERVOMOTOR - AIR CONDITIONING AMPLIFIER RESISTANCE
(PASSENGER SIDE)
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Tester connectionConditionSpecified condition
A36-5 (AOPa1) -A45-6AlwaysBelow 1 ohms
A36-6 (AOPa2) -A45-5AlwaysBelow 1 ohms
A36-7 (AOPa3) -A45-2AlwaysBelow 1 ohms
A36-9 (AOPa4) -A45-1AlwaysBelow 1 ohms
A36-26 (AOPB) - A45-4AlwaysBelow 1 ohms
A36-5 (AOPa1) - Body groundAlways10 kohms or higher
A36-6 (AOPa2) - Body groundAlways10 kohms or higher
A36-7 (AOPa3) - Body groundAlways10 kohms or higher
A36-9 (AOPa4) - Body groundAlways10 kohms or higher
A36-26 (AOPB) - Body groundAlways10 kohms or higher

Fig. 140: Checking Harness And Connector (Air Outlet Servomotor - Air Conditioning Amplifier)
(Passenger'S Side)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
This servomotor is controlled by the A/C amplifier. Air flow temperature changes when moving the air mix
damper to the target point. The target point can be detected with the air mix damper position sensor.
WIRING DIAGRAM