2001 TOYOTA SEQUOIA engine

I24837
IGTransponder Key ECU
D 3
T16
OJ43
J/C W±L
8 OP3 D6
DLC3
CG
4A
AO
± DIAGNOSTICSENGINE IMMOBILISER SYSTEM
DI±1599
1793 Author: Date:
2005 SEQUOIA (RM1146U)
Diagnosis Circuit
CIRCUIT DESCRIPTION
This circuit sends a signal to the ECU that outputs DTCs.
WIRING DIAGRAM
DIABK±03

A04550
CGOP3
1 234 5 678
91011 13 151612 14
DI±1600
± DIAGNOSTICSENGINE IMMOBILISER SYSTEM
1794 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals OP3 and CG of DLC3.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals OP3 and CG of the
DLC3.
OK:
Voltage: 10 to 14 V
OK Proceed to next circuit inspection shown in
problem symptoms table (See page DI±1573).
NG
2 Check harness and connector between transponder key ECU and DLC3, DLC3
and body ground (See page IN±35).
NG Repair or replace harness or connector.
OK
Replace transponder key ECU
(See page IN±35).

I28425
Brake Master Cylinder

Brake Fluid Level Warning Switch
Engine Room R/B

ECU±B Fuse
Light Control RheostatCombination Meter Assembly
Instrument Panel J/B

IGN 2 Fuse

GAUGE Fuse
Parking Brake SwitchIgnition Switch
Passenger Seat
Belt Warning
Skid Control ECU
± DIAGNOSTICSCOMBINATION METER SYSTEM
DI±1603
1797 Author: Date:
2005 SEQUOIA (RM1146U)

I28825
Engine Coolant Temperature Sender Gauge
Oil Pressure Sender DI±1604
± DIAGNOSTICSCOMBINATION METER SYSTEM
1798 Author: Date:
2005 SEQUOIA (RM1146U)

DI±1606
± DIAGNOSTICSCOMBINATION METER SYSTEM
1800 Author: Date:
2005 SEQUOIA (RM1146U)
Input and output signals of each ECU
Transmitting ECU
(transmitter)Receiving ECUSignalsCommunication
method
A/C ECU

Combination meter

Driver door control ECU

Passenger door control ECU
Temperature dataBEAN
A/C ECUCombination meterEngine coolant temperature dataBEAN
Combination meter

A/C ECU

Body ECU

Driver door control ECU

Passenger door control ECU

Back door ECU
Vehicle speed signalBEAN
Combination meter
Body ECU

Seat control ECUShift position signalBEAN
Combination meter

A/C ECU

Body ECU

Driver door control ECU

Passenger door control ECU

Back door ECU
Meter activation signalBEAN
Combination meterA/C ECUDisplay unit demand signalBEAN
Combination meterBody ECUEngine system signalBEAN
Body ECU

A/C ECU

Combination meter

Driver door control ECU

Passenger door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Diagnosis tool demand signalBEAN
Body ECU
A/C ECU

Combination meterBody control system signal (HEAD
signal, TAIL signal)BEAN
Body ECU

Combination meter

Driver door control ECU

Passenger door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Body control system signal (IG
signal, ACC signal, All door cour-
tesy lamp signal, Door lock signal,
Door unlock signal)
BEAN
Body ECU

Combination meter

Driver door control ECU

Passenger door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Body ECU activation signalBEAN
Body ECU

Combination meter

Driver door control ECU

Seat control ECUBody control system signal (KSW
signal)BEAN
Body ECU

Combination meter

Driver door control ECU

Passenger door control ECU

Seat control ECUDoor condition signal (Driver side
door courtesy lamp signal, Pas-
senger side door courtesy signal)
BEAN

DID8Q±01
DI±1608
± DIAGNOSTICSCOMBINATION METER SYSTEM
1802 Author: Date:
2005 SEQUOIA (RM1146U)
SYSTEM DESCRIPTION
1. METER GAUGE AND WARNING/INDICATOR
GAUGE:
ItemDetail
SpeedometerVehicle speed sensor (Direct line).
TachometerECM transmits engine speed to the meter to display.
ODO/TRIP MeterCombination meter assy.
FuelDisplays a fuel level according to a signal from the fuel sender gauge (Direct line).
Water TemperatureDisplays engine coolant temperature according to a signal from the ECM (BEAN).
Oil PressureReceives a signal from the oil pressure sender (Direct line).
Volt MeterDisplays vehicle voltage according to a voltage from the IG terminal (Direct line).
WARNING/INDICATOR:
HINT:
Combination meter bulb check is performed for 3 seconds after the ignition switch is turned ON.
ItemDetailList of indicators available for
bulb check
O/D OFFReceives a signal from the ECM (Direct line)±
TURNTurns signal switch ON (Direct line)±
BEAMReceives a signal from the body ECU (*1), Displays a signal received from the
dimmer switch (*2) (Direct line)±
SECURITYReceives a set signal from the transponder key ECU and body ECU (Direct line)±
CHARGEReceives a malfunction signal from the alternator (Direct line)
AIR BAGReceives a malfunction signal from the airbag sensor center (Direct line)
D SEAT BELTReceives the driver seat belt signal (Unfastened) from the seat belt inner front LH
(Direct line)±
DOOROpen door indicator comes on when a signal is received from the ECU (BEAN)
from each door±
A/T OIL TEMP.Warning is displayed when the oil temperature is high (Direct line)
BRAKEComes on when the parking brake switch is on or the brake fluid level warning
switch is on (Direct line)
MIL (CHECK ENGINE)Receives a malfunction signal from the ECM (Direct line)
FUEL WARNINGReceives the fuel empty signal from the fuel sender gauge (Direct line)±
ABSReceives a malfunction signal from the skid control ECU (Direct line)
WASHERWarning is displayed when the washer level is low (Direct line)±
CRUISEReceives a CRUISE on signal or malfunction signal from the ECM (Direct line)±
VSC TRACReceives a malfunction signal from the skid control ECU (Direct line)
VSC (TRAC) OFFReceives a malfunction signal from the translate ECU (Direct line)
SLIPReceives a malfunction signal from the translate ECU (Direct line)
4HIReceives a 4HI signal from the 4WD control ECU (Direct line)±
CTR DIF LOCKReceives a DIF LOCK signal from the 4WD control ECU (Direct line)±
A/T PReceives a P signal from the park/neutral position switch (Direct line)±
A/T NReceives an N signal from the park/neutral position switch (Direct line)±
A/T DReceives a D signal from the park/neutral position switch (Direct line)±
A/T 3Receives a 3 signal from the park/neutral position switch (Direct line)±
A/T 2Receives a 2 signal from the park/neutral position switch (Direct line)±
A/T LReceives an L signal from the park/neutral position switch (Direct line)±

DID8S±01
/ /
/ /
COMBINATION METER SYSTEM Check Sheet
Inspector 's name:
Customer 's NameVIN
Production Date
Licence Plate No.
Date Vehicle
Brought InOdometer Readingkm
miles
Weather Conditions
When Problem
OccurredFrequency Problem Occurs
Weather
Outside temperature Constantly  Sometimes ( times per day, month)
 Once only Date Problem First Occurred
 Fine  Cloudy  Rainy  Snowy
 Various/Others
 Hot  Warm  Cool
 Cold (Approx. 5F ( 5C))
Problem Symptom
Gauge

Malfunction in speedometer

Malfunction in tachometer

Malfunction in engine coolant temperature receiver gauge

Malfunction in fuel receiver gauge

Entire combination meter does not operate

Buzzer does not sound (Key reminder warning, Seat belt warning)

Seat belt warning for driver's seat does not operate
Others

Operating light control rheostat does not change light brightness

















Malfunction in oil pressure receiver gauge

Malfunction in volt meter DI±1612
± DIAGNOSTICSCOMBINATION METER SYSTEM
1806 Author: Date:
2005 SEQUOIA (RM1146U)
CUSTOMER PROBLEM ANALYSIS CHECK

DID8U±01
DI±1614
± DIAGNOSTICSCOMBINATION METER SYSTEM
1808 Author: Date:
2005 SEQUOIA (RM1146U)
PROBLEM SYMPTOMS TABLE
HINT:
Inspect the related ºFuseº and ºRelayº before confirming the suspected area as shown in the table below.
MALFUNCTION SYSTEM:
SymptomSuspected AreaSee page
Entire combination meter does not operate.Refer to troubleshooting proceduresDI±1628
Operating light control rheostat does not change light brightness.Refer to troubleshooting proceduresDI±1645
Seat belt warning does not operate.Refer to troubleshooting proceduresDI±1650
Key reminder warning buzzer does not sound.
1. Multiplex communication system
2. Key unlock warning switch circuit
3. Door courtesy lamp switch circuit
4. Combination meter assyDI±1892
DI±1715
DI±1728
IN±35
METER GAUGES:
SymptomSuspected AreaSee page
Malfunction in speedometerRefer to troubleshooting proceduresDI±1632
Malfunction in tachometerRefer to troubleshooting proceduresDI±1636
Malfunction in fuel receiver gaugeRefer to troubleshooting proceduresDI±1640
Malfunction in engine coolant temperature receiver gaugeRefer to troubleshooting proceduresDI±1644
Malfunction in oil pressure receiver gaugeRefer to troubleshooting proceduresDI±1654
Malfunction in volt meterRefer to troubleshooting proceduresDI±1658
WARNING LIGHTS:
SymptomSuspected AreaSee page
Check engine warning light (MIL) does not come on.
1. ECM
2. Wire harness or connector
3. Combination meter assyDI±9
±
IN±35
Discharge warning light does not come on.
1. ECM
2. Wire harness or connector
3. Combination meter assyDI±9
±
IN±35
Brake warning light does not come on.
1. Skid control ECU
2. Wire harness or connector
3. Combination meter assyDI±895
±
IN±35
ABS warning light does not come on.
1. Skid control ECU
2. Wire harness or connector
3. Combination meter assyDI±895
±
IN±35
SRS warning light does not come on.
1. Airbag sensor assy
2. Wire harness or connector
3. Combination meter assyDI±1126
±
IN±35
Open door warning light does not come on.
1. Door courtesy light switch circuit
2. Wire harness or connector
3. Combination meter assy
4. Body ECUDI±1728
±
IN±35
IN±35
Fuel level warning light does not come on.
1. Refer to troubleshooting
2. Wire harness or connector
3. Combination meter assyDI±1640
±
IN±35
Low oil pressure warning light does not come on.
1. Low oil pressure warning switch
2. Wire harness or connector
3. Combination meter assyBE±55
±
IN±35