engine TOYOTA SEQUOIA 2001 Service Repair Manual

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±639
833 Author: Date:
2005 SEQUOIA (RM1146U)
2 Perform active test
HINT:
Performing the ACTIVE TEST using the hand±held tester allows the relay, VSV, actuator and so on to oper-
ate without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one method
to shorten labor time.
It is possible to display the DATA LIST during the ACTIVE TEST.
(a) Warm up the engine.
(b) Turn the ignition switch off.
(c) Connect the hand±held tester to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Turn on the tester.
(f) Select the item ºDIAGNOSIS / ENHANCED OBD II / ACTIVE TESTº.
(g) According to the display on the tester, perform the ºACTIVE TESTº.
HINT:
While driving, the shift position can be forcibly changed with the hand±held tester.
Comparing the shift position commanded by the ACTIVE TEST with the actual shift position enables you
to confirm the problem (See page DI±567).
Standard:
ItemTest DetailsDiagnostic Note
SHIFT
[Test Details]
Operate the shift solenoid valve and set each shift position by yourself.
[Vehicle Condition]
Less than 50 km/h (31 mph)
[Others]

Press º"º button: Shift up

Press ºuº button: Shift down
Possible to check the operation of
the shift solenoid valves.
HINT:

This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.

The 4th to 5th up±shiftings must be performed with the accelerator pedal released.

The 5th to 4th down±shiftings must be performed with the accelerator pedal released.

Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.

The shift position commanded by the ECM is shown in the DATA LIST (SHIFT) display on the hand±
held tester.
OK:
Gear position changes in accordance with the tester command.
NG Repair or replace valve body

(See page AT±10).
OK

D14171
Line Pressure
Control Pressure
Current Flow to Solenoid
D14172
ON
OFF
1 cycle
D14173
DI±656
± DIAGNOSTICSAUTOMATIC TRANSMISSION
850 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P2714 Pressure Control Solenoid ºDº Performance
(Shift Solenoid Valve SLT)
SYSTEM DESCRIPTION
The linear solenoid valve (SLT) controls the transmission line
pressure for smooth transmission operation based on signals
from the throttle position sensor and the vehicle speed sensor.
The ECM adjusts the duty cycle of the SLT solenoid valve to
control hydraulic line pressure coming from the primary regula-
tor valve. Appropriate line pressure assures smooth shifting
with varying engine outputs.
(*): Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, and B
is the period of non±continuity, then
Duty Ratio = A/(A + B) x 100 (%)
DTC No.DTC Detection ConditionTrouble Area
P2714
ECM detects a malfunction on SLT (ON side) according to the
revolution difference of the turbine and the output shaft, and
also by the oil pressure. (2±trip detection logic)
Shift solenoid valve SLT remains open or closed

Valve body is blocked

Automatic transmission (clutch, brake or gear, etc.)
MONITOR DESCRIPTION
The ECM calculates the amount of heat absorbed by the friction material based on the difference in revolu-
tion (clutch slippage) between the turbine and output shaft. The ECM turns on the MIL and outputs this DTC
when the amount of heat absorption exceeds the specified value.
When the shift solenoid valve SLT remains on, oil pressure goes down and clutch engagement force de-
creases.
NOTE: If you continue driving under these conditions, the clutch will burn out and the vehicle will no longer
be drivable.
DIDJL±01

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±657
851 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR STRATEGY
Related DTCsP2714Shift solenoid valve SLT/ON malfunction
MainShift solenoid valve SLT
Required sensors/ComponentsSubValve body, ATF temperature sensor, Speed sensor (NT), Speed sensor
(NO)
Frequency of operationContinuous
DurationImmediate
MIL operation2 driving cycles
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
All:
Turbine speed sensor circuitNot circuit malfunction
Output speed sensor circuitNot circuit malfunction
Transmission Fluid Temperature Sensor
circuitNot circuit malfunction
Shift solenoid valve S1 circuitNot circuit malfunction
Shift solenoid valve S2 circuitNot circuit malfunction
Shift solenoid valve SR circuitNot circuit malfunction
Shift solenoid valve SL1 circuitNot circuit malfunction
Shift solenoid valve SL2 circuitNot circuit malfunction
Shift solenoid valve SLT circuitNot circuit malfunction
ECT (Engine coolant temperature) sensor
circuitNot circuit malfunction
KCS sensor circuitNot circuit malfunction
ETCS (Electric throttle control system)Not system down
Transmission rangeºDº
ECT40°C (104°F) or more±
Spark advance from Max. retard timing by
KCS control0° CA or more±
EngineStarting
Transfer rangeºHIGHº*1
TFT (transmission fluid temperature)10°C or more±
Transfer range ºHIGHº *1 (This condition is applied only 4WD)
*1 Following conditions met
Vehicle speed sensor circuitNot circuit malfunction
Output shaft speed sensor circuitNot circuit malfunction
Transfer output speed143 rpm or more±
NO/NOtf (Transfer input speed/Transfer
output speed)0.9 to 1.1

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±659
853 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Performing the ACTIVE TEST using the hand±held tester allows the relay, VSV, actuator and so on to oper-
ate without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one method
to shorten labor time.
It is possible to display the DATA LIST during the ACTIVE TEST.
(a) Warm up the engine.
(b) Turn the ignition switch off.
(c) Connect the hand±held tester to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Turn on the tester.
(f) Select the item ºDIAGNOSIS / ENHANCED OBD II / ACTIVE TESTº.
(g) According to the display on tester, perform the ºACTIVE TESTº.
ItemTest DetailsDiagnostic Note
LINE PRESS UP *
[Test Details]
Operate the shift solenoid SLT and raise the line pressure.
[Vehicle Condition]

Vehicle Stopped.

IDL: ON
[HINT]
OFF: Line pressure up (When the active test of ºControl the Line Pres-
sure Upº is performed, the ECM commands the SLT solenoid to turn
off).
ON: No action (normal operation)
±
*: ºLINE PRESS UPº in the ACTIVE TEST is performed to check the line pressure changes by connecting
the SST to the automatic transaxle, which is used in the HYDRAULIC TEST (See page DI±540) as well.
HINT:

The pressure values in ACTIVE TEST and HYDRAULIC TEST are different from each other.

Normally, the line pressure detected in the ACTIVE TEST is approximately half of the value detected
in the HYDRAULIC TEST's stall test.

DI±666
± DIAGNOSTICSAUTOMATIC TRANSMISSION
860 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P2740 Transmission Fluid Temperature Sensor ºBº
Circuit
DTC P2742 Transmission Fluid Temperature Sensor ºBº
Circuit Low Input
DTC P2743 Transmission Fluid Temperature Sensor ºBº
Circuit High Input
CIRCUIT DESCRIPTION
ATF (Automatic Transmission Fluid) temperature sensor No.2 is on the transmission and just in front of the
oil cooler inlet pipeline.
If ECM detects the abnormally high temperature of ATF by this sensor, it draws driver's attention by illuminat-
ing the warning lamp.
HINT:

The temperature of ATF easily rises when towing, climbing hills and in traffic, etc.

If the ATF temperature sensor No.2 becomes short±circuited, the signal that indicates the ATF temper-
ature is 150C (302F) or higher is input in ECM.
Vehicle conditions when the sensor is normal and when the sensor is short±circuited are indicated
in the table below.
ATF temperature Sensor No.2
StateDetection ConditionSymptomRecovery Condition

AT fluid temp. more than 150C
(302F).
AT Oil Temp. warning light re-
mains on
AT fluid temp. less than 135C
(275F). *2

AT fluid temp. more than 130C
(266F).
Shift point too high.
AT fluid temp. less than 110C
(230F).
Sensor is normalWhen the conditions (a) and (b)
are satisfied.
(a) AT fluid temp. more than 130C
(266F).
(b) Engine coolant temp. more
than 95C (203F).

Lock±up at 3rd gear. *1
AT fluid temp. less than 110C
(230F) *2 and engine coolant
temp. less than 95C (203F).
Sensor is short±circuited

Any conditions.

AT Oil Temp. warning light re-
mains on

Shift point too high.

Symptoms still occur
Sensor is short circuited

Engine coolant temp. more than
95C (203F).
Lock±up at 3rd gear. *1
Symptoms still occur
HINT:
*1: When AT fluid temperature is normal, transmission locks up at 5th gear with the shift lever in D position
and at 4th gear with the shift lever in 4 position.
*2: When AT fluid temperature is in normal range, it decreases to less than 135C (275F) within 5 minutes
with the shift lever in P or N position in an idling state.
DIDJN±01

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±667
861 Author: Date:
2005 SEQUOIA (RM1146U)DTC No.
DTC Detecting ConditionTrouble Area
P2740
(a) and (b) are detected momentarily within 0.5 sec. when
neither P2742 nor P2743 is detected (1±trip detection logic)
(a) ATF temperature sensor No.2 resistance is less than 25 W
(0.046 V)
(b) ATF temperature sensor No.2 resistance is more than 156
kW (4.915 V)
HINT:
Within 0.5 sec. the malfunction switches from (a) to (b) or from
(b) to (a)

Open or short in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM
P2742ATF temperature sensor No.2 resistance is less than 25 W
(0.046 V) for 0.5 sec. or more (1±trip detection logic)
Short in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM
P2743
ATF temperature No.2 sensor resistance is more than 156 kW
(4.915 V) when 15 minutes or more after the engine start
DTC is detected for 0.5 sec. or more (1±trip detection logic)
Open in ATF temperature sensor No.2 circuit

Transmission wire (ATF temperature sensor No.2)

ECM
MONITOR DESCRIPTION
The Automatic Transmission Fluid (ATF) temperature sensor converts ATF temperature to an electrical re-
sistance value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects
an open or short in the AFT temperature circuit. If the resistance value of the ATF temperature is less than
25 W (0.046 V) or more than 156 kW (4.915 V), the ECM interprets this as a fault in the ATF sensor or wiring.
The ECM will turn on the MIL and store the DTC.
MONITOR STRATEGY
P2740ATF temperature sensor/Range check (Fluttering)
Related DTCsP2742ATF temperature sensor/Range check (Low voltage)Related DTCs
P2743ATF temperature sensor/Range check (High voltage)
Required sensors/ComponentsATF temperature sensor (TFT sensor)
Frequency of operationContinuous
Duration0.5 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not present.See page DI±545
Range check (Fluttering, Low voltage)
The typical enabling condition is not avail-
able.±
Range check (High voltage)
Time after engine start15 min. or more±

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±669
863 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
According to the DATA LIST displayed by the OBD II scan tool or hand±held tester, you can read the value
of the switch, sensor, actuator and so on without parts removal. Reading the DATA LIST as the first step of
troubleshooting is one method to shorten labor time.
(a) Warm up the engine.
(b) Turn the ignition switch off.
(c) Connect the OBD II scan tool or hand±held tester to the DLC3.
(d) Turn the ignition switch to the ON position.
(e) Push the ºONº button of the OBD II scan tool or the hand±held tester.
(f) When you use the hand±held tester:
Select the item ºDIAGNOSIS / ENHANCED OBD II / DATA LISTº.
(g) According to the display on the tester, read the ºDATA LISTº.
ItemMeasurement Item/
Range (display)Normal Condition
AT FLUID TEMP 2
ATF Temp. Sensor Value/
min.: ±40C (±40F)
max.: 215C (419F)
After Stall Test;
Approx. 80C (176F)

Equal to ambient temperature when cold soak
HINT:
When DTC P2742 is output and hand±held tester output is 150C (302F) or more, there is a short circuit.
When DTC P2743 is output and hand±held tester output is ±40C (±40F), there is an open circuit.
Measure the resistance between terminal THO2 (OT2) and body ground.
Temperature DisplayedMalfunction
±40°C (±40°F)Open circuit
150°C (302°F) or moreShort circuit

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±673
867 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR DESCRIPTION
Torque converter lock±up is controlled by the ECM based on the turbine (input) speed sensor NT, output
speed sensor SP2, engine rpm, engine load, engine temperature, vehicle speed, transmission temperature,
and gear selection. The ECM determines the lock±up status of the torque converter by comparing the engine
rpm (NE) to the input turbine rpm (NT). The ECM calculates the actual transmission gear by comparing input
turbine rpm (NT) to output shaft rpm (SP2). When conditions are appropriate, the ECM requests ºlock±upº
by applying control voltage to the shift solenoid SLU. When the SLU is turned on, it applies pressure to the
lock±up relay valve and locks the torque converter clutch.
If the ECM detects no lock±up after lock±up has been requested or if it detects lock±up when it is not re-
quested, the ECM interprets this as a fault in the shift solenoid valve SLU or lock±up system performance.
The ECM will turn on the MIL and store the DTC.
Example:
When any of the following is met, the system judges it as a malfunction.
(a) There is a difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock±up.
(Engine speed is at least 70 rpm greater than input turbine speed.)
(b) There is no difference in rotation between the input side (engine speed) and output side (input turbine
speed) of the torque converter when the ECM commands lock±up off.
(The difference between engine speed and input turbine speed is less than 35 rpm.)
MONITOR STRATEGY
RltdDTCP2757Shift solenoid valve SLU/OFF malfunctionRelated DTCsP2757Shift solenoid valve SLU/ON malfunction
MainShift solenoid valve SLU
Required sensors/ComponentsSubValve body, Vehicle speed sensor, Throttle position sensor, Speed sensor
(NT), Speed sensor (NO)
Frequency of operationContinuous
OFF malfunction (A)2 sec.
DurationOFF malfunction (B)0.4 sec.Duration
ON malfunction1.8 sec.
MIL operation2 driving cycles
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
All:
Turbine speed sensor circuitNot circuit malfunction
Output speed sensor circuitNot circuit malfunction
Shift solenoid valve S1 circuitNot circuit malfunction
Shift solenoid valve S2 circuitNot circuit malfunction
Shift solenoid valve SR circuitNot circuit malfunction
Torque converter clutch pressure control
solenoid circuitNot circuit malfunction
KCS sensor circuitNot circuit malfunction
ETCS (Electric throttle control system)Not system down
Transmission rangeºDº

DI±674
± DIAGNOSTICSAUTOMATIC TRANSMISSION
868 Author: Date:
2005 SEQUOIA (RM1146U) ECT (Engine coolant temperature)
40°C (104°F) or more±
Spark advance from Max. retard timing by
KCS control0° CA or more±
EngineStarting
ECM selected gear4th or 5th
Vehicle speed25 km/h (15.5 mph) or more±
Shift solenoid valve S1 circuitNot on malfunction
Shift solenoid valve S2 circuitNot on malfunction
Shift solenoid valve SL2 circuitNot on malfunction
1±2 Shift valveNot on malfunction
Transfer neutral position switchOFF
Transfer rangeºHIGHº*1
Transfer range ºHIGHº *1 (This condition is applied only 4WD)
*1 Following conditions met
Vehicle speed sensor circuitNot circuit malfunction
Output shaft speed sensor circuitNot circuit malfunction
Transfer output speed143 rpm or more±
NO/NOtf (Transfer input speed/Transfer
output speed)0.9 to 1.1
OFF malfunction (A)
ECM lock±up commandON
(SLU pressure: 513kpa or more)
Vehicle speed±Less than 100 km/h (62.2 mph)
OFF malfunction (B)
ECM selected gear2nd
Vehicle speed2 km/h (1.2 mph) or more±
Output speed2nd " 1st down shift point or more±
Throttle valve opening angle7.0% or more at 2,000 rpm
(Conditions vary with engine speed)±
ON malfunction
ECM lock±up commandOFF
(SLU pressure: less than 4kpa)
Throttle valve opening angle9% or more±
Vehicle speed±Less than 60 km/h (37.3 mph)

± DIAGNOSTICSAUTOMATIC TRANSMISSION
DI±675
869 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL MALFUNCTION THRESHOLDS
Detection criteriaThreshold
Both of the following conditions are met: OFF malfunctions (A) and (B)
OFF malfunction (A)
Engine speed ± Turbine speed70 rpm or more
OFF malfunction (B)
Turbine speed/Output speedNot
3.30 to 7.50
ON malfunction
2 detections are necessary per driving cycle
1st detection; temporary flag ON
2nd detection; pending fault code ON
Vehicle speed must be under 10 km/h (6.2 mph) once before 2nd detection
Difference between engine speed and turbine speedLess then 35 rpm