2003 LEXUS LS430 ignition

HINT:
The automatic key code registration mode can be forced to end when at least 1 key code (immobilizer
code) for the master key has been registered.
3.REGISTRATION OF ADDITIONAL KEY (ADDITIONAL REGISTRATION)
a. Register an additional key using the hand-held tester.
HINT:
A maximum of 5 master key codes and 3 sub-key codes can be registered.
Registration mode will end if each step is not completed within the specified time.
When the ignition cylinder or the key cylinder set is replaced, remove the transmitter module
from the original master key. Then install this transmitter module to a new key and use the
new key as the master key. If necessary, use this master key to register other keys.
Additional Registration

a. Register the ECU communication ID.
1. Using SST, connect terminals TC and CG of the DLC3.
SST 09843-18040
Fig. 9: Connecting Terminals TC And CG Of DLC3 Using SST

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
2. Turn the ignition switch ON (do not start the engine) and leave it as is for 30 minutes.
3. Turn the ignition switch OFF and disconnect terminals TC and CG.
4. Check that the engine starts.
Fig. 10: Problem Symptoms Table
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.CHECK TRANSPONDER KEY AMPLIFIER

d. Measure the voltage and resistance of the connector.
Standard:
TRANSPONDER KEY AMPLIFIER - VOLTAGE TABLE
If the result is not as specified, the amplifier may have a malfunction.
e. Inspect using an oscilloscope.
Waveform 1 (Reference):
WAVEFORM 1 REFERENCE TABLE
Symbols
(Terminal No.)
Wiring Color
Terminal
Description
Condition
Specified
Condition
VC5 (T8-1) - GND
(T8-7)R - VPower sourceNo key in ignition
key cylinder ->
Key inserted0 V -> 4.6 to 5.4 V
RXCK (T8-3) -
GND (T8-7)L - VDemodulated signal
of key code dataNo key in ignition
key cylinder ->
Key insertedPulse generation
(see waveform 1)
CODE (T8-4) -
GND (T8-7)O - VDemodulated signal
of key code dataNo key in ignition
key cylinder ->
Key insertedPulse generation
(see waveform 2)
TXCT (T8-5) -
GND (T8-7)Y-B - VKey code output
signalNo key in ignition
key cylinder ->
Key insertedPulse generation
(see waveform 3)
GND (T8-7) -
Body groundV - Body groundGroundAlwaysBelow 1 ohms
TerminalRXCK - GND
Tool Setting5 V/DIV., 50 ms/DIV.
ConditionNo key in ignition key cylinder -> Key inserted

Fig. 12: Identifying Waveform 1
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 2 (Reference):
WAVEFORM 2 REFERENCE TABLE
TerminalCODE - GND
Tool Setting10 V/DIV., 20ms/DIV.
ConditionNo key in ignition key cylinder -> Key inserted

Fig. 13: Identifying Waveform 2
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 3 (Reference):
WAVEFORM 3 REFERENCE TABLE
TerminalTXCT - GND
Tool Setting5 V/DIV., 20ms/DIV.
ConditionNo key in ignition key cylinder -> Key inserted

Fig. 15: Checking Steering Lock ECU
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Disconnect the S46 ECU connector.
b. Measure the voltage and resistance of the wire harness side connector.
Standard:
STEERING LOCK ECU - VOLTAGE TABLE
Symbols
(Terminal No.)
Wiring Color
Terminal
Description
Condition
Specified
Condition
AGND (S46-18) -
Body groundV - Body groundGroundAlwaysBelow 1 ohms
CPUB (S46-1) -
GND (S46-9)V-Y - W-BBatteryAlways10 to 14 V
IG2 (S46-2) -
AGND (S46-18)B - VIgnition switchIgnition switch
OFF -> ONOV -> 10 to 14 V

If the result is not as specified, there may be a malfunction on the wire harness side.
c. Reconnect the S46 ECU connector.
d. Measure the voltage of the connector.
Standard:
STEERING LOCK ECU - VOLTAGE TABLE
If the result is not as specified, the ECU may have a malfunction.
e. Inspect using an oscilloscope.
Waveform 1 (Reference):
WAVEFORM 1 REFERENCE TABLE
KSW (S46-12) -
AGND (S46-18)LG-B - VUnlock warning
switchNo key in ignition
key cylinder ->
Key inserted10 kohms or
higher -> Below 1
ohms
PUSH (S46-11) -
AGND (S46-18)P-B - VIgnition switch
push signalIgnition switch not
pushed -> pushed10 kohms or
higher -> Below 1
ohms
Symbols
(Terminal No.)
Wiring Color
Terminal
Description
Condition
Specified
Condition
KSW (S46-12) -
AGND (S46-18)LG-B - VUnlock warning
switchNo key in ignition
key cylinder ->
Key inserted10 to 14 V -> 0 V
VC5 (S46-7) -
AGND (S46-18)R - VPower sourceIgnition switch
OFF -> ON0 V -> 4.6 to 5.4 V
RXCK (S46-8) -
AGND (S46-18)L - VTransponder key
amplifier
communication
signalIgnition switch
OFF -> ONPulse generation
(see waveform 1)
TXCT (S46-16) -
AGND (S46-18)Y-B - VTransponder key
amplifier
communication
signalIgnition switch
OFF -> ONPulse generation
(see waveform 2)
CODE (S46-17) -
AGND (S46-18)O - VTransponder key
amplifier
communication
signalIgnition switch
OFF -> ONPulse generation
(see waveform 3)
EFIO (S46-13) -
AGND (S46-18)B-Y - VECM output signalIgnition switch
OFF -> ONPulse generation
(see waveform 4)
EFII (S46-4) -
AGND (S46-18)GR-R - VECM input signalIgnition switch
OFF -> ONPulse generation
(see waveform 5)

Fig. 16: Identifying Waveform 1
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 2 (Reference):
WAVEFORM 2 REFERENCE TABLE
TerminalRXCK - GND
Tool Setting5 V/DIV., 10 ms/DIV.
ConditionIgnition switch OFF -> ON
TerminalTXCT - GND
Tool Setting5 V/DIV., 20ms/DIV.
ConditionIgnition switch OFF -> ON