LEXUS LS430 2003 Factory Repair Manual

Fig. 25: Buzzer Problem Symptoms Table
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
Refer to ON
-VEHICLE INSPECTION .
COMBINATION METER ASSY

Fig. 26: Identifying Terminals Of ECU (Combination Meter Assy)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
COMBINATION METER ASSY CONNECTOR TERMINALS REFERENCE
Symbols
(Terminals No.)Wiring
ColorTerminal DescriptionConditionSpecified
Condition
IG + (C12-1) -
Body groundY - Body
groundIgnition switch signal
(ON)Ignition switch OFF -->
ONBelow 1 V --> 10
to 14 V
MPX + (C12-2) -
Body groundGR-B -
Body groundMultiplex
communication signal--
MPX- (C12-3) -
Body groundGR-B -
Body groundMultiplex
communication signal--
S (C12-4) - Body
groundB-Y - Body
groundTachometer signalEngine runningPulse generation
(See waveform 1)
CHECK (C12-5) -
Body groundY-R - Body
groundCHECK ENGINE
signalCHECK ENGINE warning
light ON --> OFFBelow 1 V --> 10
to 14 V
TEMS (C12-6) -
Body groundY - Body
groundTEMS SPORT signalTEMS SPORT indicator
light ON --> OFFBelow 1 V --> 10
to 14 V
A/B (C12-7) - V-R (W) - ODO/TRIP signalIgnition switch ON,
ODO/TRIP switch ON -->
Below 1 V --> 4.5

Body groundBody groundOFFto 5.5 V
RESET (C12-8) -
Body groundY-G - Body
groundTRIP RESET signal
Ignition switch ON, TRIP
RESET switch ON -->
OFFBelow 1 V --> 4.5
to 5.5 V
BELT (C12-9) -
Body groundL - Body
groundSeat belt condition
signal (Passenger side)P-BELT indicator light ON
--> OFFBelow 1 V --> 10
to 14 V
S E (C12-10) -
Body groundW - Body
groundGround (Switch)AlwaysBelow 1 ohms
ES (C12-11) -
Body groundW-B - Body
groundGroundAlwaysBelow 1 ohms
+B (C12-12) -
Body groundL-Y - Body
groundBatteryAlways10 to 14 V
+B (C12-13) -
Body groundR - Body
groundBatteryAlways10 to 14 V
TURN L(C12-14)
- Body groundG-B - Body
groundTurn signal L
Ignition switch ON, turn
signal LH indicator OFF --
> ONBelow 1 V --> 10
to 14 V
TURN R (C12-15)
- Body groundL-B (SB) -
Body groundTurn signal R
Ignition switch ON, turn
signal RH indicator OFF --
> ONBelow 1 V --> 10
to 14 V
ILL- (C12-16) -
Body groundW-L - Body
groundIllumination signalIgnition switch ONPulse generation
H (C12-17) - Body
groundP - Body
groundTurn signal L
Ignition switch ON,
HEIGHT HI indicator ON
--> OFFBelow 1 V --> 10
to 14 V
SI (C12-18) -
Body groundW-G - Body
groundSpeed signal (Input)Ignition switch ON and
turn the wheel slowlyPulse generation
(See waveform 2)
+S (C12-19) -
Body groundV-W - Body
groundSpeed signal (Output)Ignition switch ON and
turn the wheel slowlyPulse generation
E2 (C12-22) -
Body groundW-B - Body
groundGroundAlwaysBelow 1 ohms

Fig. 27: Identifying Waveform 1
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 1 (Reference):
WAVEFORM 1 (REFERENCE)
ItemContents
Tool setting5V/DIV, 10 ms/DIV
Vehicle conditionEngine idle speed

Fig. 28: Identifying Waveform 2
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Waveform 2 (Reference):
WAVEFORM 2 (REFERENCE)
HINT:
As vehicle speed increases, the cycle of the signal waveform narrows.
COMBINATION METER INNER CIRCUIT
ItemContents
Tool setting5V/DIV, 20 ms/DIV
Vehicle conditionDriving at approx. 20 Km/h (12 mph)

Fig. 29: Combination Meter Inner Circuit Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Fig. 30: Combination Meter Connector Terminals Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.CHECK DLC3
a. The vehicle's combination meter (ECU) uses CAN and the ISO 9141-2 for communication
protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO
9141-2 format.

Fig. 31: Identifying DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DLC3 CONNECTOR TERMINALS REFERENCE
HINT:
If the display shows UNABLE TO CONNECT TO VEHICLE when you have connected the cable of the
hand-held tester to the DLC3, turned the ignition switch ON and operated the tester, there is a problem on
the vehicle side or tool side.
Symbols (Terminals No.)Terminals DescriptionConditionSpecified condition
CG(4) - Body groundChassis groundAlwaysBelow 1 ohms
BAT(16) - Body groundBattery positiveAlways11 to 14 V
CANH(6) - CANL(14)HIGH-level CAN bus lineIG switch OFF54 ohms to 67ohms
CANH(6) - Body groundHIGH-level CAN bus lineIG switch OFF1 Mohms or higher
CANH(6) - CG(4)HIGH-level CAN bus lineIG switch OFF3 Kohms or higher
CANL(14) - Body groundLOW-level CAN bus lineIG switch OFF1 Mohms or higher
CANL(14) - CG(4)LOW-level CAN bus lineIG switch OFF3 Kohms or higher

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.
2.DIAGNOSIS CHECK (MULTI- INFORMATION DISPLAY)
a. Switch to diagnosis mode
1. Connect terminal 13 (TC) and 4 (CG) of the DLC3 using SST.
Fig. 32: Identifying Terminal 13 (TC) And 4 (CG) Of DLC3

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
2. The display in the warning area shows "DIAG" when the ignition switch is turned to the ON
position.
3. Each system can be switched by pushing the "DISP1" switch on the steering pad switch.
HINT:
Dia
gnosis checks for the EFI, VSC and CRUISE systems can be done by using the displayed items

in the warning area.
SFI (EFI) system (see SYSTEM DIAGRAM )
VSC system (see HOW TO PROCEED WITH TROUBLESHOOTING )
CRUISE system (see HOW TO PROCEED WITH TROUBLESHOOTING)