2001 TOYOTA SEQUOIA ECU

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)

DID8P±01
I28566
Seat Position
Control ECU
A/C ECU (Integration
Control Panel) BEANBody ECU
Back Door ECU
ECM
Light Control
Rheostat
Vehicle Speed
Sensor
Oil Pressure
Sender Gauge
Fuel Sender Gauge
Seat Inner
Belt Switch
Park/neutral
Position Switch
Turn Signal
Flasher Relay
Washer Level SensorKey Unlock
Warning Switch
Door Courtesy
Lamp Switch
Parking Brake Switch
Transponder
Key ECU
4WD Control ECU
Airbag Sensor
Center ECU Combination
Meter
Skid Control ECU
Suspension
Control ECU
Translate ECU
Overhead Module
(Garage Door
Opener)BEAN
BEAN
BEAN
BEAN
BEAN BEAN
± DIAGNOSTICSCOMBINATION METER SYSTEM
DI±1605
1799 Author: Date:
2005 SEQUOIA (RM1146U)
SYSTEM DIAGRAM

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

± DIAGNOSTICSCOMBINATION METER SYSTEM
DI±1607
1801 Author: Date:
2005 SEQUOIA (RM1146U)Driver door control ECU

Combination meter

Body control ECU

Passenger door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Driver door control ECU activation
signalBEAN
Passenger door control ECU

Combination meter

Body control ECU

Driver door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Passenger door control ECU ac-
tivation signalBEAN
Sliding roof control ECU

Combination meter

Body control ECU

Driver door control ECU

Passenger door control ECU

Back door ECU
Sliding roof control ECU activation
signalBEAN
Seat control ECU

Combination meter

Body control ECU

Driver door control ECU

Passenger door control ECU
Seat control ECU activation signalBEAN
Back door ECU

Combination meter

Body control ECU

Driver door control ECU

Passenger door control ECU

Seat control ECU
Back door control ECU activation
signalBEAN

A/C ECU

Combination meter

Driver door control ECU

Passenger door control ECU

Seat control ECU

Sliding roof control ECU

Back door ECU
Back door ECUDiagnosis tool answer signalBEAN

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)±

± DIAGNOSTICSCOMBINATION METER SYSTEM
DI±1609
1803 Author: Date:
2005 SEQUOIA (RM1146U)A/T R
Receives an R signal from the park/neutral position switch (Direct line)±
TAIL/HEADReceives a dimmer signal from the body ECU (BEAN)±
TIRE PRESSUREReceives a low tire pressure signal from the tire pressure monitor ECU (Direct line)
4LOReceives a 4LO signal from the 4WD control ECU (Direct line)±
MAIN REQD (Blinks)Blinks when 4,500 miles have been traveled, after ODO/TRIP switch is set (Direct
line)
MAIN REQD (Comes on)Blinks when 5,000 miles have been traveled, after ODO/TRIP switch is set (Direct
line)
RSCA OFFReceives an RSCA OFF signal from the airbag sensor center (Direct line)
HIReceives a suspension position HI signal from the suspension control ECU (Direct
line)
NReceives a suspension position N signal from the suspension control ECU (Direct
line)
LOReceives a suspension position LO signal from the suspension control ECU (Direct
line)
AHC MAN.Receives a suspension control manual signal from the suspension control ECU
(Direct line)
*1: w/ Day time running light
*2: w/o Day time running light
BUZZER:
ItemDetail
Key ReminderBuzzer is ON: Ignition switch is OFF, key is inserted, and door is open.
Fasten BeltBuzzer is ON: Ignition switch is ON and seat belt is unfastened.
2. COMBINATION METER IN SEQUOIA HAS THE FOLLOWING FEATURES:
(a) Built±in buzzer for the reminder system (key and seat belt)
(b) Integrated trip and odometer knobs

Press and release knob to scroll through trip ºAº, trip ºBº, and odometer features.

Press and hold the trip knob to reset trip meter functions.
(c) Oil maintenance indicator

When 4,500 miles have been traveled, after the ODO/TRIP switch is set, the maintenance indica-
tor begins to blink for 15 seconds after the ignition switch is turned to the ON position.

When 5,000 miles have been traveled, after the ODO/TRIP switch is set, the maintenance indica-
tor comes on.

Press and hold the trip knob to reset the oil maintenance indicator.
(d) Rotate knob to adjust interior illumination