2001 TOYOTA SEQUOIA ECO mode

DIDDC±01
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±725
919 Author: Date:
2005 SEQUOIA (RM1146U)
FAIL±SAFE CHART
FAIL±SAFE FUNCTION
When a rear air suspension system malfunction is detected under normal control operation, the suspension
control ECU will suspend the switch control of the height control operation.
FAIL±SAFE CHART
DTC No.Malfunction ItemFail±safe OperationFail±safe Deactivation
Condition
C1714/14Malfunction in height
control sensor
Auto mode:
When the target vehicle height, just before fail, is higher than
ºNº, vehicle height is lowered for 20 seconds and then sys-
tem control shuts down.
Manual mode:
When the target vehicle height, just before switching to the
manual mode, is higher than ºNº, the switch operation to
lower vehicle height is available for only 20 seconds.
Return to normal condition.
C1733/33Open or short in gate
solenoid valveSystem control shuts down.Return to normal condition.
C1734/34Open or short in level-
ing solenoid valveSystem control shuts down.Return to normal condition.
C1735/35Open or short in ex-
haust solenoid valve
Auto mode:
After vehicle height is raised through control, the system
shuts down.
Manual mode:
When vehicle height is lower than ºNº, only the switch opera-
tion to raise vehicle height is available.
Return to normal condition.
C1741/41Open or short in AIR
SUS relay circuit
Auto mode:
After vehicle height is lowered through control, the system
shuts down.
Manual mode:
When vehicle height is higher than ºNº, only the switch op-
eration to lower vehicle height is available.
Return to normal condition.
C1742/42Lock in height control
compressor motor
Auto mode:
After vehicle height is lowered through control, the system
shuts down.
Manual mode:
When vehicle height is higher than ºNº, only the switch op-
eration to lower vehicle height is available.
After interrupting for 70 min-
utes, restart the control.
C1751/51
Powered continuously
or powered excessive-
ly in height control
compressor motor
Auto mode:
After vehicle height is lowered through control, the system
shuts down.
Manual mode:
When vehicle height is higher than ºNº, only the switch op-
eration to lower vehicle height is available.
After interrupting for 70 min-
utes, restart the control.
C1761/61Malfunction in suspen-
sion control ECUSystem control shuts down.Return to normal condition.
C1774/74Power voltage
droppedSystem control shuts down.Return to normal condition.
U0100/65Lost communication
with TL ECUSystem control continues.Return to normal condition.

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±

DI±782
± DIAGNOSTICSAIR SUSPENSION SYSTEM
976 Author: Date:
2005 SEQUOIA (RM1146U)
DTC U0100/65 Lost Communication with ECM/PCM
CIRCUIT DESCRIPTION
The ECM sends signals such as engine speed signal, transmission signal, shift position signal, L4 switch
signal, TC terminal signal (diagnosis mode signal) to the suspension control ECU, etc. when the air suspen-
sion system is in operation.
DTC No.DTC Detecting ConditionTrouble Area
U0100/65
The suspension control ECU detects the following conditions
simultaneously:
1. Ignition switch ON
2. Vehicle speed signal is more than 30 km/h (18.5 mph)
3. No communication from ECM continues for more than 3
seconds

ECM

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).
DIDEG±01

± 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

F19451
C6
Combination
MeterSuspension Control
ECU
I18
Ignition SW
Engine Room J/B Instrument Panel J/B B±O
W±R11
7 1H
1JIGN1
1C
1C32
B±RMAN. 24
13 LG11
S25 VN
5
IG2 AM2 6
W±R
B
Battery 1
2D AM2
2C1
B5 4F10
FL Block
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±789
983 Author: Date:
2005 SEQUOIA (RM1146U)
Height Control Manual Indicator Lamp Circuit
CIRCUIT DESCRIPTION
When manual mode is selected by pressing the height control mode select switch, the manual indicator lamp
comes on. (For the wiring diagram of the height control mode select switch circuit, see page DI±778.) If the
suspension control ECU detects a problem, the height control manual indicator lamp blinks while suspend-
ing the height control function. At the same time, the suspension control ECU records a DTC in the memory.
Connect terminals TC and CG of the DLC3 to make the height control manual indicator lamp blink and output
DTCs.
WIRING DIAGRAM
DIDEN±01

± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
DI±801
995 Author: Date:
2005 SEQUOIA (RM1146U)

When the spare tire is not within the receivable range of the electric wave, a signal may not be
received because spare tires are fixed. Accordingly, the system may not function properly. If
there is a possibility that the TPWS system does not receive a signal from the spare tire, rotate
the tire 90°.
HINT:

If any other wheels than the specified ones are used, the system may not function properly because
the radio waves are differently transmitted from the tire pressure sensor.

Depending on the tire type, the system may not function properly even though the specified wheels
are used.
(c) The average use life of the grommet of the tire pressure monitor valve sub±assy is approximately 5
years, at which time it must be replaced.
(d) After removing and installing the ECU or a sensor, output a diagnosis code and check that it is a normal
code.
3. FUNCTION OF COMPONENTS
ComponentsFunction
Tire pressure monitor valve sub±assy
Combined as a single unit with a disc wheel air valve, it measures tire pressure and
temperature and transmits an ID number for measurement value and identification.
Built±in the battery.
Tire pressure monitor receiver assyReceives and transmits a necessary signal from the transmitter to the tire pressure
monitor ECU.
Tire pressure monitor ECU
Receives the signal from the receiver and identifies it as vehicle's own signal. If the
measurement value is equal to or lower than the specified value, it transmits a sig-
nal so that the air pressure warning lamp on the combination meter comes on.
Tire pressure warning lampLocated in the combination meter, it informs the driver of lowered tire air pressure
and system failure.
Tire pressure warning reset switchEnters the initialization mode for tire or wheel replacement, or tire rotation
4. TIRE PRESSURE WARNING RESET SWITCH

By operating the tire pressure warning reset switch, the tire pressure monitor ECU can be set to issue
a warning at an inflation pressure that corresponds to the type of tires. Therefore, the dealer must set
the warning threshold to the proper value in order to comply with the local regulations.

Operate the tire pressure warning reset switch only after the inflation pressures of all 5 tires (including
the spare) have been adjusted on the vehicle.

To initialize the system, press and hold the tire pressure warning reset switch for 3 seconds or longer
with the ignition switch ON. After the system has been initialized, the warning lamp blinks 3 times (1
second ON, 1 second OFF).

During initialization, the tire pressure monitor valve sub±assy measures the inflation pressure of the
tires, and registers the signals that are transmitted into the tire pressure monitor ECU at a frequency
of one per minute. The initialization process is completed when the signals from the 5 tires have been
received.

The initialization process is canceled if the ignition switch is turned OFF during initialization. To initialize
again, the tire pressure warning reset switch must be pressed again. For this reason, once the tire pres-
sure warning reset switch has been pressed, turning OFF the ignition switch is not recommended for
a minimum of 20 minutes.

F19181
DI±812
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
1006 Author: Date:
2005 SEQUOIA (RM1146U)
(e) Drive the vehicle at 12mph (20 km/h) or more for 10 se-
conds or more.
(f) Loosen the valve core and rapidly reducing the pressure
(20 kPa above/15 sec.).
HINT:
The transmitter ID can be transmitted by rapidly reducing the
tire air pressure.
(g) Check that the tire pressure warning system test mode
DTCs are erased.
SIGNAL
CHECK DTCTest SignalSignal Check DTC Clear Condition
C2181C2185Transmitter DataReceive DATA from the transmitter which has a registered ID
in TPWS ECU
C2191Vehicle Speed SignalVehicle speed of 12 mph (20 km/h) or more is detected for 3
seconds or more
(h) Result
HINT:
After the signal check is complete, check for a DTC and signal check DTC to confirm the system status.
SIGNAL CHECK DTC is outputRepair the faulty part and enter SIGNAL CHECK again
SIGNAL CHECK DTCs are clearedNo problem
(i) End of SIGNAL CHECK
After completing test mode (SIGNAL CHECK), turn the ignition switch OFF and disconnect the tester.

D13491
DLC3:
BAT
SIL CG
DIDK3±01
F19148
Combination Meter
Tire Pressure
Warning Lamp DI±816
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
1010 Author: Date:
2005 SEQUOIA (RM1146U)
DIAGNOSIS SYSTEM
1. CHECK BATTERY VOLTAGE
Battery voltage: 11 to 14 V
If the voltage is below 11 V, recharge the battery before pro-
ceeding.
2. CHECK DLC3
The vehicle's tire pressure monitor ECU uses ISO 9141±2 for
communication. The terminal arrangement of DLC3 complies
with SAE J1962 and matches the ISO 9141±2 format.
Verify the conditions listed in the table below:
Terminal No.Disc.Connection / Voltage or ResistanceCondition
7SILBus + Line / Pulse generationDuring transmission
4CGChassis Ground to Body Ground / 1 W or lessAlways
16BATBattery Positive to Body Ground / 10 to 14 VAlways
HINT:
If the hand±held tester display shows UNABLE TO CONNECT
TO VEHICLE when the cable of the hand±held tester is con-
nected to DLC3, the ignition switch is turned to the ON position
and the tester is operated, there is a problem on the vehicle side
or tester side.

If communication is normal when the tester is connected
to another vehicle, inspect DLC3 on the original vehicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tester itself, so consult the Service Department listed in
the tester's instruction manual.
3. DIAGNOSIS SYSTEM
(a) Warning lamp
(1) The tire pressure warning lamp blinks when there is
any malfunction in the tire pressure warning sys-
tem.
NOTICE:
When the malfunction has been corrected, the tire pres-
sure warning lamp does not come on.
(b) DTCs (Normal mode)
(1) DTCs are memorized in the tire pressure monitor
ECU and read by the blinks of the tire pressure
warning lamp or using the hand±held tester (see
page DI±820.
(c) Test mode
(1) By switching from normal mode into test mode (in-
put signal check), you can inspect the tire pressure
monitor receiver assy, each tire pressure monitor
valve sub±assy and vehicle speed sensor (see
page DI±810).