2003 LEXUS LS430 air conditioning

Fig. 176: Inspecting Air Conditioning Amplifier (RHI, RLO, RSLO)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: Go to STEP 5
OK: Go to STEP 7
5.INSPECT REAR BLOWER RESISTOR
a. Remove the rear blower resistor.
b. Measure the resistance according to the value (s) in the table below.
Standard:
REAR BLOWER RESISTOR RESISTANCE
NG: REPLACE BLOWER RESISTOR
Tester connectionConditionSpecified condition
R30-1 - R30-3Always5.2 to 6.0 ohms
R30-2 - R30-3Always10.5 to 12.1 ohms

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

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