2003 LEXUS LS430 Temperature sensor

AOPa2 - GND
(A36-6 - A11-1)P-B - W-
BAir outlet servomotor
operation signal
(Passenger side)During actuator check mode.
Change display code 0 to display
code 9.Pulse
generation
AOPa3 - GND
(A36-7 - A11-1)P-G - W-
BAir outlet servomotor
operation signal
(Passenger side)During actuator check mode.
Change display code 0 to display
code 9.Pulse
generation
AOPa4 - GND
(A36-9 - A11-1)P-L - W-
BAir outlet servomotor
operation signal
(Passenger side)During actuator check mode.
Change display code 0 to display
code 9.Pulse
generation
S5-5 - SG-7(1)
(A36-11 - A36-
15)
R - W-L
Cool air bypass damper
position sensor signal
(Driver side)
Ignition switch ON.4.5 to 5.5 V
S5-5 - SG-7(2)
(A36-11 - A36-
15)
R - W-L
Cool air bypass damper
position sensor signal
(Passenger side)
Ignition switch ON.4.5 to 5.5 V
AMPB - GND
(A36-13 - A11-1)Y - W-B
Air mix servomotor
operation voltage
(Passenger side)
Always10 to 14 V
AIF - SG (A36-
16 - A37-19)G-R - W-
BAir inlet damper position
sensor signalIgnition switch ON. Push REC
switch.Below 1.0 V
AIF - SG (A36-
16 - A37-19)G-R - W-
BAir inlet damper position
sensor signalIgnition switch ON. Push FRESH
switch.10 to 14 V
AIR - SG (A36-
17 - A37-19)G-Y - W-
BAir inlet damper position
sensor signalIgnition switch ON. Push FRESH
switch.Below 1.0 V
AIR - SG (A36-
17 - A37-19)G-Y - W-
BAir inlet damper position
sensor signalIgnition switch ON. Push REC
switch.10 to 14 V
TE - SG-7 (A36-
20 - A36-15)L-Y - W-
LEvaporator temperature
sensor signalIgnition switch ON. Evaporator
temperature 0 °C (32 °F).2.0 to 2.4V
TE - SG-7 (A36-
20 - A36-15)L-Y - W-
LEvaporator temperature
sensor signalIgnition switch ON. Evaporator
temperature 15 °C (59 °F).1.4 to 1.8 V
TPBDr - SG-7
(A36-24 - A36-
15)B-R - W-
LCool air bypass
servomotor operation
signal (Driver side)Change display code 9 to display
code 0.3.5 to 4.5 V
TPBDr - SG-7
(A36-24 - A36-
15)B-R - W-
LCool air bypass
servomotor operation
signal (Driver side)Change display code 2 to display
code 3.0.5 to 1.8 V
AOPB - GND
(A36-26 - A11-1)Y-R - W-
BAir outlet servomotor
operation voltage
(Passenger side)
Always10 to 14 V
(1)w/o LEXUS Navigation System
(2)w/ Rear A/C

HINT:
The followings are the possible items to be customized.
AIR CONDITIONER
AIR CONDITIONER CUSTOMIZE PARAMETERS
SMOK - Body
ground (L14-16
- Body ground)L - Body
groundSmoke sensor
operation signal
Ignition switch ON. Rear A/C switch to
AUTO. By using cigarette smoke. Ignition
switch ON. Rear A/C switch to AUTO. By
not using cigarette smoke.
Above 4.0 V
Below 1.0 V
AUTO - Body
ground (L14-17
- Body ground)W -
Body
groundAuto switch
signal
Ignition switch ON. Rear A/C rear seat
AUTO indicator lights up. Ignition switch
ON. Rear A/C rear seat AUTO indicator
does not light up.
Below 1.0 V 10 to
14 V
RHR - Body
ground (L14-18
- Body ground)V -
Body
groundRear blower
motor operation
signal
Ignition switch ON. Rear A/C manual
mode. Rear A/C blower motor does not
operate. Ignition switch ON. Rear A/C
manual mode. Rear A/C blower motor
speed LO or HI. During actuator check
mode. Display code 0. Display code 2.
10 to 14 V Below
1.0 V 10 to 14 V
Below 1.0 V
RFR - Body
ground (L14-19
- Body ground)Y -
Body
groundRear blower
motor operation
signal
Ignition switch ON. Rear A/C blower
motor speed to except HI. Ignition switch
ON. Rear A/C blower motor speed to HI.
During actuator check mode. Display code
0. Display code 2.
10 to 14 V Below
1.0 V 10 to 14 V
Below 1.0 V
FRS - Body
ground (L14-20
- Body ground)B -
Body
groundExhaust damper
servomotor
operation signal
Ignition switch ON. Front A/C blower
motor operates. Push "FRS" switch.
Ambient temperature below -1 °C Ignition
switch ON. Front A/C blower motor
operates. Push "REC" switch.
10 to 14 V Below
1.0 V
(1)w/ Rear A/C
DISPLAY (ITEM)DEFAULTCONTENTSSETTING

1.STEP MOTORS INITIALIZING FUNCTION
STEP motor initializing procedure (Automatic initializing)
1. When the battery is reconnected and the ignition switch is turned to the ON position for the first
time, the initializing function of the STEP motors is activated. In this case, the "FRONT DEF"
indicator blinks.
SET TEMP SHIFT
(Set Temperature
Shift)
NORMALTo control with the shifted temperature
against the display temperature.+2C/+1C/ NORMAL -
1C / -2C
AIR INLET MODE
(Air Inlet Mode)AUTO
In case of turning the A/C ON when you
desire to make the compartment cool down
quickly, this is the function to change the
mode automatically to RECIRCULATED
mode.
MANUAL / AUTO
COMPRESSOR
MODE (Compressor
Mode)
AUTO
Function to turn the A/C ON automatically
by pressing the AUTO button when the
blower is ON and the A/C is OFF.
MANUAL / AUTO
COMPRS/DEF OPER
(Compressor/Air Inlet
DEF Operation)
LINK
Function to turn the A/C ON automatically
linking with the FRONT DEF button when
A/C is OFF.
NORMAL / LINK
MOTOR INITIALIZ
(STEP Motor
Initializing (IG/off))
OFFFunction to initialize the STEP motor after
the ignition switch is OFF.ON / OFF
EVAP CTRL
(External Variable
Control OFF)
AUTO
Function to set the evaporator control to the
AUTOMATIC position (AUTO) to save
power or to the coldest position
(MANUAL) to dehumidify the air and to
prevent the windows from fogging up.
MANUAL / AUTO
GAS SENS SHIFT
(Shift Emission Gas
Sensor Sensitivity)
NORMALFunction to change the sensitivity of the
exhaust gas sensor.
MU MORE /MORE / LI
MORE / NORMAL / LI
LESS / LESS / MU
LESS
AUTO MODE
(Cancel Auto Mode)AUTOFunction to swing the vent vans
automatically when A/C is ON.MANUAL / AUTO
BUTTON PRS BUS
(Cancel Operating
Switch Sound)
ONFunction to sound a buzzer when a button
is pressed.OFF / ON
FILTER SENS (Shift
Filter Clog Sensitivity)NORMALFunction to change the sensitivity of the air
conditioning filter choking sensor.LESS / NORMAL /
MORE
FOOT AIR LEAK
(Cancel Air Outlet
Foot II)
ONFunction to cut off the airstream felt
underfoot while the vehicle is moving.OFF / ON

Fig. 31: Rear A/C Problem Symptoms Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Air Purifier
Fig. 32: Air Purifier Problem Symptoms Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Intelligent Swing Register
Fig. 33: Intelligent Swing Register Problem Symptoms Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
If a malfunction code is displayed during the DTC check (sensor check), check the circuit listed for that code in
the table below.
DIAGNOSTIC TROUBLE CODE CHART
DTCDescription
DTC B1411ROOM TEMPERATURE SENSOR CIRCUIT
DTC B1412AMBIENT TEMPERATURE SENSOR CIRCUIT
DTC B1413EVAPORATOR TEMPERATURE SENSOR CIRCUIT
DTC B1415AIR DUCT SENSOR CIRCUIT (DRIVER SIDE)
DTC B1416AIR DUCT SENSOR CIRCUIT (PASSENGER SIDE)
DTC B1418EMISSION GAS SENSOR CIRCUIT
DTC B1421SOLAR SENSOR CIRCUIT (PASSENGER SIDE)
DTC B1423PRESSURE SWITCH CIRCUIT
DTC B1424SOLAR SENSOR CIRCUIT (DRIVER SIDE)
DTC B1428REAR SOLAR SENSOR CIRCUIT
DTC B1432AIR INLET DAMPER POSITION SENSOR CIRCUIT
DTC B1434MAX COOL DAMPER POSITION SENSOR CIRCUIT (DRIVER SIDE)
DTC B1435MAX COOL DAMPER POSITION SENSOR CIRCUIT (PASSENGER SIDE)

Fig. 34: Diagnostic Trouble Code Information Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
*1 If the room temperature is approximately -20°C (-4°F) or lower, DTC B1411/11 may be output even
though the system is normal.
*2 If the ambient temperature is approximately -50°C (-58°F) or lower, a DTC may be output even
though the system is normal.
*3 If the check is being performed in a dark place, DTC B1421/21 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1421/21 is still displayed, there could be trouble in the solar sensor circuit.
*4 If the check is being performed in a dark place, DTC B1424/24 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1424/24 is still displayed, there could be trouble in the solar sensor circuit.
*5 If the check is being performed in a dark place, DTC B1421/21 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1421/21 is still displayed, there could be trouble in the solar sensor circuit.
CIRCUIT DESCRIPTION
This sensor detects the interior temperature that is used as the basis for temperature control and sends
appropriate signals to the A/C amplifier.
Fig. 35: DTC Detection Item Trouble Area Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM

Fig. 36: Room Temperature Sensor Circuit
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE ON HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position and push the hand-held tester main switch on.
c. Select the item below in the DATA LIST, and read the display on the hand-held tester.
DATA LIST / AIR CONDITIONER:
DATA LIST / AIR CONDITIONER
OK:
The display is as specified in the normal condition.
Result:
ItemMeasure Item/Display (Range)Normal ConditionDiagnostic
Note
ROOM
TEMPRoom temperature sensor / min.: -6.5°C (20.3°F)
max.: 57.25°C (126.95°F)Actual room temperature
is displayed-

AIR CONDITIONER TEST RESULT
B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
A
2.INSPECT COOLER (ROOM TEMPERATURE SENSOR) THERMISTOR
a. Remove the cooler (room temperature sensor) thermistor.
b. Measure the resistance according to the value (s) in the table below.
Standard:
COOLER (ROOM TEMPERATURE SENSOR) THERMISTOR RESISTANCE
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C
Tester connectionConditionSpecified condition
A14-1 - A14-210°C (50°F)3.00 to 3.73 kohms
A14-1 - A14-215°C (59°F)2.45 to 2.88 kohms
A14-1 - A14-220°C (68°F)1.95 to 2.30 kohms
A14-1 - A14-225°C (77°F)1.60 to 1.80 kohms
A14-1 - A14-230°C (86°F)1.28 to 1.47 kohms
A14-1 - A14-235°C (95°F)1.00 to 1.22 kohms
A14-1 - A14-240°C (104°F)0.80 to 1.00 kohms
A14-1 - A14-245°C (113°F)0.65 to 0.85 kohms
A14-1 - A14-250°C (122°F)0.50 to 0.70 kohms
A14-1 - A14-255°C (131°F)0.44 to 0.60 kohms
A14-1 - A14-260°C (140°F)0.36 to 0.50 kohms

Fig. 37: Identifying Terminals Of A14 A/C Room Temperature Sensor Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
As the temperature increases, the resistance decreases (see the
graph below).