DIDIS±01
D14143
SST
SST
DI±540
± DIAGNOSTICSAUTOMATIC TRANSMISSION
734 Author: Date:
2005 SEQUOIA (RM1146U)
HYDRAULIC TEST
1. PERFORM HYDRAULIC TEST
Measure the line pressure.
NOTICE:
Perform the test at the normal operating ATF (Auto-
matic Transmission Fluid) temperature: 50 to 80°C
(122 to 176°F).
The line pressure test should always be carried out in
pairs. One technician should observe the conditions
of wheels or wheel stoppers outside the vehicle while
the other is performing the test.
Be careful to prevent SST hose from interfering with
the exhaust pipe.
This check must be conducted after checking and ad-
justing engine.
Perform under condition that A/C is OFF.
When conducting stall test, do not continue more
than 10 seconds.
(1) Warm up the ATF (Automatic Transmission Fluid).
(2) Lift the vehicle up.
(3) Remove the test plug on the transmission case cen-
ter right side and connect SST.
SST 09992±00095 (09992±00231, 09992±00271)
(4) Fully apply the parking brake and chock the 4
wheels.
(5) Start the engine and check idling speed.
(6) Keep your left foot pressing firmly on the brake ped-
al and shift into D position.
(7) Measure the line pressure when the engine is idling.
(8) Depress the accelerator pedal all the way down.
Quickly read the highest line pressure when engine
speed reaches stall speed.
(9) In the same manner, do the test in R position.
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±699
893 Author: Date:
2005 SEQUOIA (RM1146U)
Input and output signals of each ECU.
Transmitting ECUReceiving ECUSignalCommunication method
ECM
Translate ECU
Suspension control
ECU
Engine speed signal
Transmission signal
Shift position signal
L4 switch signal
TC signal
CAN
Translate ECUSuspension control
ECUVehicle wheel speed signal
TS signalCAN
Suspension control ECUTranslate ECUAir suspension setting signalCAN
DI±702
± DIAGNOSTICSAIR SUSPENSION SYSTEM
896 Author: Date:
2005 SEQUOIA (RM1146U)
3. FUNCTION OF MAIN COMPONENTS
ComponentOutline
Height Control Mode Select SwitchUsed to select vehicle height control mode (Auto/Manual).
Used to operate or stop auto leveling control.
Height Control SwitchAuto mode: Used to select vehicle height (HIGH, NORMAL, LOW).
Manual mode: Used to select vehicle height optionally.
Height Control SensorConverts the vertical change of the rear axle, in proportion to the standard, to sig-
nals and detects vehicle height.
Height Control Indicator Lamp (Combination Meter)Auto mode: Target vehicle height is displayed (HIGH, NORMAL, LOW).
Manual mode: Current vehicle height is displayed (HIGH, NORMAL, LOW).
Height Control Manual Indicator Lamp (Combination Meter)
Comes on during manual mode.
Blinks when the suspension control ECU detects a system malfunction.
Blinks during test mode.
Displays output DTC.
Stop light SwitchDetects braking condition.
Used to clear DTCs.
Pneumatic Cylinder (Height Control Cylinder Assy)Supports the vehicle body and adjusts the vehicle height.
Height Control Compressor Assy (Compressor/Height Con-
trol Dryer)The compressor generates compressed air that is necessary to raise vehicle
height and supplies it to the height control cylinder assy.
The dryer removes moisture from the compressed air.
Exhaust Solenoid ValveDrains the air in the height control cylinder assy when vehicle height is lowered.
(Built into the height control compressor assy)
Leveling Solenoid ValveOpens or closes the passage between the height cylinder assy and height control
compressor assy.
Gate Solenoid ValveOpens or closes the passage between the right and left height control cylinder assy
(Built into the leveling solenoid valve).
Suspension Control ECU
Estimates vehicle condition based on the signals from sensors and switches, and
outputs the control signals to the compressor and valves.
Blinks the height control manual indicator light when a system malfunction is de-
tected.
Air Suspension RelaySupplies power to the height control compressor assy.
Door Courtesy Switch (Body ECU)Detects whether the 5 doors, including the back door, are opened or closed, and
sends the signals to the suspension control ECU.
ECMSends the engine speed signal, etc. to the suspension control ECU through CAN
communication.
Speed Sensor (Skid Control ECU)Sends the vehicle wheel speed signal, etc. to the suspension control ECU through
CAN communication via the translate ECU.
DIDDE±01
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±727
921 Author: Date:
2005 SEQUOIA (RM1146U)
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
By accessing the DATA LIST displayed by the hand±held tester, you can read the value of the switches and
sensors and so on without removing any parts. Reading the DATA LIST is the first step of troubleshooting
and is one method to shorten labor time.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Following the display on the tester, read the DATA LIST.
AIR SUSPENSION:
ItemMeasurement Item / Range (Dis-
play)Normal ConditionDiagnostic Note
VEHICLE SPD
Vehicle speed reading / min.: 0
km/h (0 mph), max.: 255 km/h
(158 mph)
Actual vehicle speedSpeed indicated on the combina-
tion meter
FR WHEEL SPD
Wheel speed (Front right) reading /
min.: 0 km/h (0 mph), max.: 255
km/h (159 mph)
Actual vehicle speedSpeed indicated on the speedome-
ter
FL WHEEL SPD
Wheel speed (Front left) reading /
min.: 0 km/h (0 mph), max.: 255
km/h (159 mph)
Actual vehicle speedSpeed indicated on the speedome-
ter
IG VOLTAGEECU power supply voltage / min.:
0 V, max.: 25.5 VActual ECU power supply voltage:
10 to 14 V±
POWER VOLTAGE+B power source voltage / min.: 0
V, max.: 25.5 VActual battery power supply volt-
age: 10 to 14 V±
STEERING ANG
Steering angle sensor reading /
min.: ±49150.5 deg, max.: 49152
degActual steering angle /
Left turn: reading increases
Right turn: reading increasesZero point is set at the point when
battery is connected
ENGINE SPDCrankshaft position sensor read-
ing / min.: 0 rpm, max.: 25,500 rpmActual engine speedSpeed indicated on the combina-
tion meter
HEIGHT SW DOWNHeight control switch (DOWN) /
ON or OFFON: Height control switch
ºDOWNº button pressed
OFF: ±
±
HEIGHT SW UPHeight control switch (UP) / ON or
OFFON: Height control switch ºUPº
button pressed
OFF: ±
±
HEIGHT SW HOLDHeight control mode select switch
/ ON or OFFON: Height control mode select
switch pressed
OFF: ±
±
STOP LIGHT SWStop light switch / ON or OFFON: Brake pedal depressed
OFF: Brake pedal released±
DOOR SWDoor courtesy light switch / ON or
OFFON: Open each door
OFF: Close all doors±
L4 SW4LO switch / ON or OFFON: 2WD/4HI switch pressed
OFF: ±±
TSTS terminal / ON or OFFON: During test mode
OFF: Normal mode±
TCTC terminal / ON or OFFON: DTC recorded
OFF: No DTC recorded±
SOL SLRLHeight control valve solenoid (Lev-
elling solenoid valve) / ON or OFFON: Leveling solenoid operated
OFF: Leveling solenoid not oper-
ated
±
SOL SLRGHeight control valve solenoid
(Gate solenoid valve) / ON or OFFON: Gate solenoid operated
OFF: Gate solenoid not operated±
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±783
977 Author: Date:
2005 SEQUOIA (RM1146U)
DTC U0122/67 Lost Communication with Translate ECU
CIRCUIT DESCRIPTION
The translate ECU sends signals such as vehicle wheel speed signal, TS terminal signal (test mode signal)
to the suspension control ECU, etc. when the air suspension system is in operation.
DTC No.DTC Detecting ConditionTrouble Area
U0122/67
The suspension control ECU detects the following conditions
simultaneously:
1. Ignition switch ON
2. No communication from translate ECU continues for more
than 3 seconds
Translate ECU
Suspension control ECU
Communication circuit
INSPECTION PROCEDURE
HINT:
This circuit uses CAN for communication. Therefore, if there are any malfunctions in the communication cir-
cuit, one or more DTCs in the CAN communication system is/are output.
1 Go to CAN communication system (See page DI±1065).
DIDEH±01
DIDJT±01
F19148
Combination Meter
Tire Pressure
Warning Lamp DI±796
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
990 Author: Date:
2005 SEQUOIA (RM1146U)
TIRE PRESSURE WARNING SYSTEM
PRECAUTION
NOTICE:
When disconnecting the battery terminal, initialize the following system after the terminal is recon-
nected.
System NameSee Page
Back Door Power Window Control SystemBE±77
1. TIRE PRESSURE WARNING SYSTEM PRECAUTION
(a) When the tire pressure warning lamp comes on, immedi-
ately check the tire pressure of the tire and adjust it to the
specified pressure. (The tire pressure warning lamp
comes on if there is an open in the tire pressure warning
lamp circuit.)
NOTICE:
Check the spare tire as well since this system monitors
pressure of all tires, including the spare.
Tire sizeFrontRearSpare
P245 / 70 R 16220 kPa (2.2 kgf/cm2, 32 psi)240 kPa (2.4 kgf/cm2, 35 psi)240 kPa (2.4 kgf/cm2, 35 psi)
P265 / 70 R 16220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)
P265 / 65 R 17220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)
(b) When the tire pressure warning lamp blinks, there is a
malfunction in the system. Check for DTCs.
(c) It is necessary to register the transmitter ID in the tire pres-
sure monitor ECU when replacing the tire pressure moni-
tor valve sub±assy and/or tire pressure monitor ECU (see
page DI±805).
(d) When replacing the tire pressure monitor ECU.
(1) Using the DATA LIST, read the transmitter IDs regis-
tered in the ECU and make a note of them before
removing the tire pressure monitor ECU.
(2) Register the transmitter IDs after installing a new
tire pressure monitor ECU.
(e) When replacing the tire pressure monitor valve sub±assy.
(1) Make a note of the 7 digit number (transmitter ID)
written on the tire pressure monitor valve sub±assy
when replacing the tire pressure monitor valve sub±
assy. Register the transmitter IDs in the tire pres-
sure monitor ECU after replacing the tire pressure
monitor valve sub±assy and installing the tires and
wheels on the vehicle.
F19132
Transmitter ID
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
DI±797
991 Author: Date:
2005 SEQUOIA (RM1146U)
NOTICE:
The transmitter ID is written on the tire pressure monitor
valve sub±assy and ID can not be seen after installing the
tire pressure monitor valve sub±assy on the tire and wheel.
Therefore, make a note of the transmitter ID before instal-
ling the tire pressure monitor valve sub±assy.
2. IN CASE OF TIRE AND WHEEL REPLACEMENT
(a) When tires and wheels are replaced, register the transmitter ID without fail.
3. IN CASE OF TIRE ROTATION OR REPLACEMENT OF TIRE PRESSURE MONITOR ECU, TIRE
PRESSURE MONITOR VALVE SUB±ASSY, OR TIRES WITH DIFFERENT TIRE PRESSURE
(a) Initialize the tire pressure warning system after one of the following is performed:
Replacing the tire pressure monitor ECU or the tire pressure monitor valve sub±assy
Tire rotation
Replacing tires with different tire pressure
HINT:
The tire pressure warning system will not operate properly if it is not initialized (see page DI±808).
4. FAIL±SAFE FUNCTION
(a) When a system malfunction occurs in the tire pressure warning system, the tire pressure warning lamp
blinks and informs the driver of the system failure.
(b) The result of this diagnosis is stored in the tire pressure monitor ECU.
DIDJW±01
F19887
Tire Pressure Monitor Valve Sub±assy
Tire Pressure
Warning Reset
Switch
Tire Pressure
Monitor ECU
Meter
DLC3
Tire Pressure Monitor Valve Sub±assyTire Pressure Monitor Receiver Assy
DI±800
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
994 Author: Date:
2005 SEQUOIA (RM1146U)
SYSTEM DESCRIPTION
1. DESCRIPTION OF SYSTEM
(a) A tire pressure monitor valve sub±assy equipped with a tire pressure sensor and a transmitter and is
installed in a tire wheel assy. The sensor measures the tire pressure and the measured value and
transmitter ID are transmitted to the tire pressure monitor receiver assy on the body as radio waves
and then sent to the tire pressure monitor ECU from the tire pressure monitor receiver. If the transmitter
ID has already been registered, the ECU compares the measured air pressure value with the standard
value. When the value is less than the standard value registered in the tire pressure monitor ECU, the
warning lamp on the combination meter comes on.
To address the differences in the air pressure settings by the type of tires, or the differences in
pressure between the front and rear tires, a tire pressure warning reset switch has been newly
adopted.
Along with the adoption of the tire pressure warning reset switch, the warning operation has been
changed.
TPWS transmitters with different bending angles as the tire pressure monitor valve sub±assy
have been provided for steel wheels with center ornaments. (They are not interchangeable with
aluminum wheels or steel wheels with full wheel caps.)
2. WHEN TIRE PRESSURE WARNING LAMP IS LIT
(a) When the warning lamp does not go off, or when it comes on during driving, check tire pressure. If the
warning lamp is lit even though the tire pressure is correctly adjusted, the tire could be punctured.
(b) Under the following conditions, the system may not function properly.
The areas, facilities or devices that use similar radio frequencies are located in the vicinity of the
vehicle.
A radio device of similar frequency is used in the vehicle.
A lot of snow or ice is stuck to the vehicle, especially onto the wheels and around the wheel
houses.
The battery of the sensor has been depleted.
The tires without tire pressure monitor valve sub±assy are used.
Tire chains are used.