2003 LEXUS LS430 air condition

Fig. 177: Inspecting Rear Blower Resistor
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
6.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BLOWER
RESISTOR) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
AIR CONDITIONING AMPLIFIER - BLOWER RESISTOR RESISTANCE
Tester connectionConditionSpecified condition
A46-1 (RLO) -R30-1AlwaysBelow 1 ohms
A46-1 (RLO) - Body groundAlways10 kohms or higher
A46-2 (RSLO) - R30-3AlwaysBelow 1 ohms
A46-2 (RSLO) - Body groundAlways10 kohms or higher

Fig. 178: Checking Harness And Connector (Air Conditioning Amplifier - Blower Resistor)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig. 180: Checking Harness And Connector (Blower Motor -Blower Resistor)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE OR REPLACE HARNESS OR CONNECTOR
REPLACE REAR AIR CONDITIONING AMPLIFIER (SEE OVERHAUL
)
CIRCUIT DESCRIPTION
The exhaust damper control servomotor is controlled by the luggage room J/B ECU and moves the rear exhaust
damper to the desired position.
WIRING DIAGRAM
Fig. 181: Exhaust Damper Control Servomotor Circuit

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
a. PERFORM ACTUATOR CHECK

a. Warm up the engine.
b. Set the actuator check mode (see ACTUATOR CHECK
).
c. Press the driver temperature up switch, and change to STEP operation.
d. Press the driver temperature up switch, and check the air flow by hand.
ACTUATOR INSPECTION
A/P: Air purifier
OK: Exhaust damper position changes in accordance with each display code.
NG: Go to STEP 2
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
b.INSPECT EXHAUST SERVOMOTOR
a. Remove the exhaust servomotor.
b. Connect the positive (+) lead from the battery to terminal 7 and negative (-) lead to terminal 1, then
check that the lever turns to the "ROO" position smoothly.
c. Connect the positive (+) lead from the battery to terminal 7 and negative (-) lead to terminal 3, then
check that the lever turns to the "DIO" position smoothly.
d. Connect the positive (+) lead from the battery to terminal 7 and negative (-) lead to terminal 5, then
check that the lever turns to the "EXO" position smoothl
y.
Display CodeRear A/C ModeExhaust DamperCondition
0OFFExhaust positionNo air comes out
1LOA/PDiffusion positionNo air comes out
2HIA/PDiffusion positionNo air comes out
3 to 4HI A/CCool positionCool air comes out
5LOA/CCool positionCool air comes out
6 to 9OFFCool positionNo air comes out

OK: Go to next step
c.CHECK HARNESS AND CONNECTOR (EXHAUST SERVOMOTOR - REAR AIR
CONDITIONING AMPLIFIER) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
EXHAUST SERVOMOTOR - REAR AIR CONDITIONING AMPLIFIER RESISTANCE
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Tester connectionConditionSpecified condition
A46-10 (IG) - R31-7AlwaysBelow 1 ohms
A46-14 (ROO) - R31-1AlwaysBelow 1 ohms
A46-12 (DIO) - R31-3AlwaysBelow 1 ohms
A46-13 (EXO) - R31-5AlwaysBelow 1 ohms
A46-6 (GND) - R31-8AlwaysBelow 1 ohms
A46-10 (IG) - Body groundAlways10 kohms or higher
A46-14 (ROO) - Body groundAlways10 kohms or higher
A46-12 (DIO) - Body groundAlways10 kohms or higher
A46-13 (EXO) - Body groundAlways10 kohms or higher
A46-6 (GND) - Body groundAlwaysBelow 1 ohms

Fig. 183: Checking Harness And Connector (Exhaust Servomotor -Rear Air Conditioning
Amplifier)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE REAR AIR CONDITIONING AMPLIFIER (SEE OVERHAUL
)
CIRCUIT DESCRIPTION
The rear magnetic valve is controlled by luggage room J/B ECU and A/C amplifier operation.
WIRING DIAGRAM
Fig. 184: Rear Magnetic Valve Circuit

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT LUGGAGE ROOM J/B ECU (RMGV - BODY GROUND)

a. Remove the luggage room J/B ECU with connectors still connected.
b. Measure the voltage according to the value (s) in the table below.
Standard:
LUGGAGE ROOM J/B ECU (RMGV - BODY GROUND) VOLTAGE
NG: Go to STEP 3
Fig. 185: Inspecting Luggage Room J/B ECU (RMGV
- Body Ground)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
2.INSPECT REAR AIR CONDITIONING AMPLIFIER (RMGV - BODY GROUND)
a. Remove the A/C amplifier with connectors still connected.
b. Measure the voltage according to the value (s) in the table below.
Tester connectionConditionSpecified
condition
L14-11 (RMGV) - Body
groundTurn the ignition switch to ON position Turn the rear A/C
switch to ON positionBelow 1 V

Standard:
REAR AIR CONDITIONING AMPLIFIER (RMGV - BODY GROUND) VOLTAGE
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (REAR AIR CONDITIONING
AMPLIFIER - REAR MAGNETIC VALVE)
Fig. 186: Inspecting Rear Air Conditioning Amplifier (RMGV
- Body Ground)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
3.CHECK HARNESS AND CONNECTOR (LUGGAGE ROOM J/B - REAR MAGNETIC VALVE)
(SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
Tester connectionConditionSpecified
condition
A46-5 (RMGV) - Body
groundTurn the ignition switch to ON position Turn the rear A/C
switch to ON positionBelow 1 V