2003 LEXUS LS430 ignition

If the communication is normal when the tool is connected to another vehicle, inspect the DLC3 on
the original vehicle.
If the communication is still impossible when the tool is connected to another vehicle, the problem
is probably in the tool itself, so consult the Service Department listed in the tool's instruction
manual.
1.INDICATOR CHECK
a. Turn the ignition switch to the ON position while pressing the A/C control AUTO switch and R/F
(Recirculation/Fresh) switch simultaneously.
Fig. 13: Identifying Auto Switch (W/O LEXUS Navigation System)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Check that the all indicators come on and go off 4 times in succession at 1 second intervals.
HINT:
After the indicator check is completed, the system enters the DTC mode automatically.
Press the "OFF" switch to cancel the indicator mode.

Fig. 15: Blinking Pattern Indictor Light
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
2.DTC CHECK USING HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Read the DTC following the prompts on the tester screen. Please refer to the hand-held tester
operator's manual for further details.
c. Clear the DTCs.
HINT:
After repairing the malfunctions, clear the DTC.
1. Connect the hand-held tester to the DLC3.
2. Turn the ignition switch to the ON position.
3. Erase the DTCs followin
g the prompts on the tester screen.

Fig. 16: Connecting Hand-Held Tester To DLC3
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
Refer to the intelligent tester II operator's manual for further details.
1.ACTUATOR CHECK
a. Turn the ignition switch to the ON position while pressing the A/C control AUTO switch and R/F
(Recirculation / Fresh) switch simultaneously.
b. Press the R/F (Recirculation / Fresh) switch.
c. As each damper, motor and relay automatically operate the actuator check at 1 second intervals
from STEP No. 1 to No. 10 continuousl
y, check the temperature and air flow visually and by hand.

Fig. 21: Display Code - Conditions Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.DATA LIST
HINT:
From the DATA LIST displayed on the hand-held tester, you can read the values of the displays, sensors,
actuators and so on without parts removal. Reading the DATA LIST as the first STEP of troubleshooting
is one way to shorten labor time.
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. From the display on the tester, select the "DATA LIST".
DATA LIST / AIR CONDITIONER:
DATA LIST / AIR CONDITIONER
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic
Note

DATA LIST / ENGINE AND ECT / ALL:
DATA LIST / ENGINE AND ECT / ALL
2.ACTIVE TEST
HINT:
Performing the ACTIVE TEST
using the hand-held tester allows the relays, VSV, actuators and so on to
operate without parts removal. Performing the ACTIVE TEST
as the first STEP of troubleshooting is
one way to shorten labor time.
It is possible to display the DATA LIST on the hand-held tester during the ACTIVE TEST.
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. From the display on tester, perform the "ACTIVE TEST
".
ACTIVE TEST / AIR CONDITIONER:
ACTIVE TEST / AIR CONDITIONER
FOOT AIR
LEAKFoot air leak / ON, OFFCustomized value will be displayed-
DESTINATION
Destination / DOMEST, USA,
EUROPE, AUSTRAL,
MIDEAST, NO INFO
Changes with destinations-
REAR SOLAR
SENSRear solar sensor / min.: 0 max.:
255Changes depending on brightness-
NOX GAS SENSEmission gas Nox sensor / min.: 0
max.: 255Increases as the gas amount increases-
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic
Note
REG PRESS
SENSRegulator pressure sensor / min.:
0 max.: 255Actual regulator pressure is displayed-
FILTER FLOW
VOLFilter flow volume / min.: 0 max.:
65535Actual filter flow volume is displayed-
REG CTRL
CURRNTRegulator control current / min.: 0
A max.: 255 A--
HUMIDITY
SENSHumidity sensor / min.: 0% max.:
100%Actual room humidity is displayed-
#CODESNumber of Trouble Codes / min.:
0 max.: 255Number of DTCs will be displayed-
ItemMeasurement Item/Display (Range)Normal ConditionDiagnostic Note
A/C SIGA/C signal/ ON or OFFA/C ON: ON-

Fig. 22: Identifying Air Conditioning Amplifier Connector Front View
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
AIR CONDITIONING AMPLIFIER CONNECTOR SPECIFICATIONS
ItemTest Details / Display (Range)Diagnostic Note
ACTUATOR CHECKActuator check / OFF, ON-
Symbols
(Terminal No.)Wiring
colorTerminal DescriptionConditionSpecification
GND - Body
ground (A11-1 -
Body ground)W-B -
Body
groundGround for main power
supplyAlwaysBelow 1.0
ohms
MPX+ (A11-2)GR-BMultiplex communication
systemMultiplex communication circuit-
ACC - GND
(A11-3 - A11-1)GR - W-
BPower source (ACC)Turn ignition switch to ACC.10 to 14 V
MPX- (A11-4)GR-BMultiplex communication
systemMultiplex communication circuit-
BLW - GND
(A11-5 - A11-1)LG-B -
W-BBlower motor speed
control voltageBlower fan speed OFF --> M2 -->
HIPulse
generation
SOL+ - SOL-
(A11-6 - A11-7)P - Y-BCompressor operation
signalA/C magnetic clutch to ON.Pulse
generation
RDFGR - GND
(A11-8 - A11-1)W - W-BRear defogger operation
voltageIgnition switch ON. Rear
defogger switch to OFF.10 to 14 V
RDFGR - GND
(A11-8 - A11-1)W - W-BRear defogger operation
voltageIgnition switch ON. Rear
defogger switch to ON.Below 1.0 V
IG - GND (A11-9
- A11-1)LG-R -
W-BPower source (IG)Ignition switch ON.10 to 14 V

IG - GND (A11-9
- A11-1)LG-R -
W-BPower source (IG)Ignition switch OFF.0 V
TSDr - GND
(A11-19 - A11-1)L - W-BSolar sensor signal (Driver
side)Ignition switch ON. Solar sensor
subjected to electric light.0.8 to 4.3 V
TSDr - GND
(A11-19 - A11-1)L - W-BSolar sensor signal (Driver
side)Ignition switch ON. Solar sensor
covered by a cloth.Below 0.8 V
TSPa - GND
(A11-20 - A11-1)G-R - W-
BSolar sensor signal
(Passenger side)Ignition switch ON. Solar sensor
subjected to electric light.0.8 to 4.3 V
TSPa - GND
(A11-20 - A11-1)G-R - W-
BSolar sensor signal
(Passenger side)Ignition switch ON. Solar sensor
covered by a cloth.Below 0.8 V
+B - GND (A11-
21 - A11-1)B-Y - W-
BPower source (Back-up)Always10 to 14 V
DGS - SG-1
(A11-29 - A13-8)B - YExhaust gas sensor signal
After 30 seconds from Ignition
switch ON and the sensor is
exposed to the exhaust gas.
1.0 to 4.5 V
DS1 - GND
(A12-1 - A11-1)V - W-BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
Symbols
(Terminal No.)Wiring
colorTerminal DescriptionConditionSpecification
DS2 - GND
(A12-2 - A11-1)G - W-BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
PS1 - GND (A12-
3 - A11-1)R-B - W-
BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
PS2 - GND (A12-
4 - A11-1)B - W-BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
PS3 - GND (A12-
5 - A11-1)P - W-BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
PS4 - GND (A12-
6 - A11-1)Y-R - W-
BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
DUAL - DrGND
(A12-7 - A12-11)O - LG-RDual temperature control
signalIgnition switch ON. Dual switch
ON.Below 1.0 V
DUAL - DrGND
(A12-7 - A12-11)O - LG-RDual temperature control
signalIgnition switch ON. Dual switch
OFF.10 to 14 V

DS3 - GND
(A12-8 - A11-1)B-R - W-
BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
DS4 - GND
(A12-9 - A11-1)G-B - W-
BSwing grill STEP motor
signal
Ignition switch ON. Blower
motor: Operating Mode selector:
BI-LEVEL Intelligent swing
register: ON
Pulse
generation
DUIND+ -
DUIND - (A12-
10 - A12-13)G-R - B-
WDriver temperature and
passenger temperature
communication signalDriver temperature and passenger
temperature are different.5 to 14 V
DUIND+ -
DUIND- (A12-10
- A12-13)G-R - B-
WDriver temperature and
passenger temperature
communication signalDriver temperature and passenger
temperature are the same.Below 1.0 V
S5-2 - SG-5
(A12-15 - A13-
12)
V-R - LGPressure sensor operation
voltageIgnition switch ON.4.5 to 5.5 V
S5-4 - TSRr(2)
(A12-16 - A11-
30)
GR - W-LRear solar sensor signalIgnition switch ON. Rear solar
sensor subjected to electric light.0.8 to 4.3 V
S5-4 - TSRr(2)
(A12-16 - A11-
30)
GR - W-LRear solar sensor signalIgnition switch ON. Rear solar
sensor covered by a cloth.Below 1.0 V
PRS - SG-5
(A12-17 - A13-
12)
V - LGPressure sensor signalRefrigerant pressure 0 Mpa (0
kgf.cm, 0 psi).0.5V
PRS - SG-5
(A12-17 - A13-
12)
V - LGPressure sensor signalRefrigerant pressure 2.9 Mpa (30
kgf.cm, 427 psi).4.5 V
TAMOUT - GND
(1) (A12-18 -
A11-1)L - W-BVehicle speed signalIgnition switch ON.Pulse
generation
PaDN - PaGND
(A12-19 - A12-
12)R-W - Y-
RTemperature control
switch signal (Passenger
side)Push passenger temperature
switch OFF.10 to 14 V
PaDN - PaGND
(A12-19 - A12-
12)R-W - Y-
RTemperature control
switch signal (Passenger
side)Push passenger temperature
switch ON.Below 1.0 V
PaUP - PaGND
(A12-20 - A12-
12)
W - Y-R
Temperature control
switch signal (Passenger
side)Push passenger temperature
switch OFF.10 to 14 V
Symbols
(Terminal No.)Wiring
colorTerminal DescriptionConditionSpecification
PaUP - PaGND
(A12-20 - A12-W - Y-RTemperature control
switch signal (Passenger
Push passenger temperature Below 1.0 V