2001 TOYOTA SEQUOIA coolant change

MA003±50
MA±4
± MAINTENANCEUNDER HOOD
51 Author: Date:
2005 SEQUOIA (RM1146U)
UNDER HOOD
GENERAL MAINTENANCE
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.

Failure to do even one item can cause the engine to run poorly and increase exhaust emissions.
2. WINDSHIELD WASHER FLUID
Check that there is sufficient fluid in the tank.
3. ENGINE COOLANT LEVEL
Check that the coolant level is between the FULL and LOW lines on the see±through reservoir.
4. RADIATOR AND HOSES
(a) Check that the front of the radiator is clean and not blocked with leaves, dirt or bugs.
(2UZ±FE engine: See page CO±14)
(b) Check the hoses for cracks, kinks, rot or loose connections.
5. BATTERY ELECTROLYTE LEVEL
Check that the electrolyte level of all battery cells is between the upper and lower level lines on the case.
6. BRAKE AND CLUTCH FLUID LEVELS
Check that the brake and clutch fluid levels are near the upper level line on the see±through reservoirs.
7. ENGINE DRIVE BELTS
Check all drive belts for fraying, cracks, wear or oiliness.
8. ENGINE OIL LEVEL
Check the level on the dipstick with the engine turned off.
9. POWER STEERING FLUID LEVEL
(a) Check the level on the dipstick.
(b) The level should be in the HOT or COLD range depending on the fluid temperature.
10. AUTOMATIC TRANSMISSION FLUID LEVEL
(a) Park the vehicle on a level surface.
(b) With the engine idling and the parking brake applied, shift the selector into all positions from the P to
L, and then shift into the P position.
(c) Pull out the dipstick and wipe off the fluid with a clean rag. Re±insert the dipstick and check that the
fluid level is in the HOT range.
(d) Do this check with the fluid at normal driving temperature (70 ± 80°C, 158 ± 176°F).
HINT:
Wait until the engine cools down (approx. 30 min.) before checking the fluid level after extended driving at
high speeds, in hot weather, in heavy traffic or pulling a trailer.
11. EXHAUST SYSTEM
(a) Visually inspect for cracks, holes or loose supports.
(b) If any change in the sound of the exhaust or smell of the exhaust fumes is noticed, find the cause and
correct.

A23544
40 mph (64 km/h)
Idling
IG SW OFF ECT:
75C (167F) or higher
Vehicle Speed
Warming up(5)(6)
10 minutes
or more(7)
10 seconds
or more4 seconds
or moreTime At Least 3 times
(8) (9)
(10) Accelerator Pedal
DepressedAccelerator Pedal
Released (Fuel±cut)
± DIAGNOSTICSENGINE
DI±31
225 Author: Date:
2005 SEQUOIA (RM1146U)
5. AIR±FUEL RATIO (A/F) AND OXYGEN SENSOR (HO2) MONITOR (ACTIVE AIR±FUEL RATIO
CONTROL TYPE)
(a) Preconditions
The monitor will not run unless:

2 minutes or more have elapsed since the engine was started.

The Engine Coolant Temperature (ECT) is 75C (167F) or higher.

Air±fuel ratio feedback control is performed.

Fuel±cut control is performed for 8 seconds or more.
(b) Drive Pattern
(1) Connect the hand±held tester to DLC3.
(2) Turn the ignition switch to ON.
(3) Clear DTCs (see page DI±43).
(4) Start the engine, and warm it up until the ECT reaches 75C (167F) or higher.
(5) Drive the vehicle at 40 mph (64 km/h) or more for at least 10 minutes.
(6) Change the transmission to 2nd gear.
(7) Accelerate the vehicle to 30 mph (48 km/h) or more by depressing the accelerator pedal for at
least 10 seconds.
(8) Soon after performing step (8) above, release the accelerator pedal for at least 4 seconds without
depressing the brake pedal, in order to execute fuel±cut control.
(9) Stop the vehicle and allow the engine to idle for 10 seconds or more.
(10) Allow the vehicle to decelerate until the vehicle speed declines to less than 6 mph (10 km/h).
(11) Repeat steps from (8) through (10) above at least 3 times in one driving cycle.
(c) Monitor Status
(1) Check the Readiness Monitor status displayed on the tester.
(2) If the status does not switch to COMPL (complete), make sure that the preconditions have been
met, and then perform steps from (5) through (11) in Drive Pattern above.

± DIAGNOSTICSENGINE
DI±119
313 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0115 Engine Coolant Temperature Circuit
DTC P0117 Engine Coolant Temperature Circuit Low
Input
DTC P0118 Engine Coolant Temperature Circuit High
Input
CIRCUIT DESCRIPTION
A thermistor is built in the Engine Coolant Temperature (ECT) sensor and changes the resistance value ac-
cording to the engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as the Intake Air Temperature (IAT) sen-
sor.
HINT:
If the ECM detects the DTC ºP0115, P0117 or P0118º, it operates the fail±safe function in which the ECT
is assumed to be 80C (176F).
DTC No.Proceed toDTC Detection ConditionTrouble Area
P0115Step 1
Open or short in engine cool-
ant temperature sensor circuit
for 0.5 sec.
P0117Step 4
Short in engine coolant tem-
perature sensor circuit for 0.5
sec.
Open or short in engine coolant temperature sensor circuit

Engine coolant temperature sensor

ECM
P0118Step 2
Open in engine coolant tem-
perature sensor circuit for 0.5
sec.
HINT:
After confirming DTC ºP0115, P0117 or P0118º, use the OBD II scan tool or the hand±held tester to confirm
the engine coolant temperature from the DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL.
Displayed TemperatureMalfunction
±40°C (±40°F)Open circuit
140°C (284°F) or moreShort circuit
MONITOR DESCRIPTION
The ECT (Engine Coolant Temperature) sensor is used to monitor the engine coolant temperature. The ECT
sensor has a thermistor that varies its resistance depending on the temperature of the engine coolant. When
the coolant temperature is low, the resistance in the thermistor increases. When the temperature is high, the
resistance drops. The resistance varies as output voltage from the sensor changes.
The ECM monitors the sensor voltage and uses this value to calculate the engine coolant temperature.
When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a fault
in the ECT sensor and sets a DTC.
DI3HO±13

DI±126
± DIAGNOSTICSENGINE
320 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever this DTC is
not presentSee page DI±18
Case 1 (When temperature is fixed between 35C (95F) and 60C (140F)):
Cumulative idle off period250 sec.±
Speed increase 30 km/h (18.6 mph) or
more10 times±
Engine coolant temperature35C (95F)60C (140F)
Intake air temperature±6.7C (20F)±
Case 2 (When temperature is fixed at 60C (140F) or more):
Engine coolant temperature at engine
start60C (140F)±
Intake air temperature±6.7C (20F)±
Stop and goOnce or more (Stop for 20 sec. or more and accelerate to more than 70 km/h (43.5 mph)
with in 40 sec.)
Steady driving and stop *Once or more
*: Vehicle is driven by 65 km/h (40.4 mph) or more for 30 sec. or more and the vehicle speed reaches 70
km/h (43.5 mph). The vehicle is decelerated from 65 km/h (40.4 mph) to 3 km/h (1.86 mph) or less within
35 sec. and stopped for 10 sec.
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Case1 (When temperature is fixed between 35C (95F) and 60C (140F)):
Change of engine coolant temperature valueLess than 3C (5.4F)
Case2 (When temperature is fixed at 60C (140F) or more):
Change of engine coolant temperature value1C (1.8F) or less
COMPONENT OPERATING RANGE
Standard Value
Engine coolant temperature changes with the actual engine coolant temperature.
INSPECTION PROCEDURE
HINT:

If DTC P0115, P0116, P0117, P0118 and P0125 are output simultaneously, ECT sensor circuit may
be open or shorted. Perform the troubleshooting of DTC P0115, P0117 or P0118 first.

Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions
when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the
vehicle was running or stopped, if the engine was warmed up or not, if the air±fuel ratio was lean or
rich, as well as other data from the time when a malfunction occurred.
Replace engine coolant temperature sensor.

B17394
Fuel
Compensation
Amount
1.35
1.0
0.65 +35 (%):
Lean Malfunction Threshold
±35 (%):
Rich Malfunction Threshold
P0171, P0174:
P0172, P0175:
± DIAGNOSTICSENGINE
DI±167
361 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR DESCRIPTION
Under closed±loop fuel control, fuel injection volumes that deviate from those estimated by the ECM cause
changes in the long±term fuel trim compensation value. The long±term fuel trim is adjusted when there are
persistent deviations in the short±term fuel trim values. Deviations from the ECM's estimated fuel injection
volumes also affect the average fuel trim learning value, which is a combination of the average short±term
fuel trim (fuel feedback compensation value) and the average long±term fuel trim (learning value of the air±
fuel ratio). If the average fuel trim learning value exceeds the malfunction thresholds, the ECM interprets
this a fault in the fuel system and sets a DTC.
Example:
The average fuel trim leaning value is more than +35 % or less than ±35 %, the ECM interprets this as a fuel
system malfunction.
MONITOR STRATEGY
P0171Fuel system lean (Bank 1)
RltdDTCP0172Fuel system rich (Bank 1)Related DTCsP0174Fuel system lean (Bank 2)
P0175Fuel system rich (Bank 2)
Main sensors/componentsFront oxygen sensor
Required sensors/componentsRelated sensors/componentsEngine coolant temperature sensor, Mass air flow
meter, Crankshaft position sensor
Frequency of operationContinuous
Duration10 sec.
MIL operation2 driving cycles
Sequence of operationNone

± DIAGNOSTICSENGINE
DI±171
365 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check air induction system (See page SF±1).
CHECK:
Check the air induction system for vacuum leaks.
NG Repair or replace air induction system.
OK
4 Perform active test (A/F control).
(a) Connect the hand±held tester to the DLC3.
(b) Start the engine and turn the tester ON.
(c) Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
(d) On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST /
A/F CONTROL.
(e) Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT
button to change the fuel injection volume).
(f) Monitor the voltage outputs of A/F and HO2 sensors(AFS B1S1 (AFS B2S1) and O2S B1S2 (O2S
B2S2)) displayed on the tester.
HINT:

The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection
volume by 25 %.

Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Standard:
Tester Display
(Sensor)Injection VolumesStatusVoltages
AFS B1S1 (AFS B2S1)
(A/F)+25 %RichLess than 3.0
AFS B1S1 (AFS B2S1)
(A/F)±12.5 %LeanMore than 3.35
O2S B1S2 (O2S B2S2)
(HO2)+25 %RichMore than 0.55
O2S B1S2 (O2S B2S2)
(HO2)±12.5 %LeanLess than 0.4
Result:
Status
AFS B1S1
(AFS B2S1)Status
O2S B1S2
(O2S B2S2)A/F Condition and
A/F Sensor ConditionMisfiresSuspected Trouble AreasProceed To
Lean/RichLean/RichNormal''C
LeanLeanActual air±fuel ratio leanMay occur

PCV valve and hose

PCV hose connections

Injector blockage

Gas leakage from exhaust system

Air induction system

Fuel pressure

Mass Air Flow (MAF) meter

Engine Coolant Temperature (ECT)
sensor
A

S01196S01699
30
20
10
5
3
02040 0.11
0.3
0.2 0.52
60 80 100 ±20
(±4) (104) (140) (176)(32) (68) (212)
A21042
Ohmmeter
Acceptable
TEMPERATURE C (F)
RESISTANCE KW
± DIAGNOSTICSENGINE
DI±203
397 Author: Date:
2005 SEQUOIA (RM1146U)
18 Check engine coolant temperature sensor.
PREPARATION:
Remove the engine coolant temperature sensor.
CHECK:
Measure the resistance between the terminals of the engine
coolant temperature sensor.
Resistance:
Tester ConnectionSpecified Condition
1 ± 22.32 to 2.59 kW (20C (68F))
1 ± 20.310 to 0.326 kW (80C (176F))
NOTICE:
In case of checking the engine coolant temperature sensor
in the water, be careful not to allow water to go into the ter-
minals. After checking, dry the sensor.
HINT:
Alternate procedure: Connect an ohmmeter to the installed en-
gine coolant temperature sensor and read the resistance. Use
an infrared thermometer to measure the engine temperature in
the immediate vicinity of the sensor. Compare these values to
the resistance/temperature graph. Change the engine temper-
ature (by warming up or cooling down) and repeat the test.
NG Replace
engine coolant temperature sensor.
OK
19 Switch step by number of misfire cylinder (Refer to the result of step 4).
High misfire rate cylinderProceed to
1 or 2 cylindersA
More than 3 cylindersB
B Go to step 5.
A
Check for intermittent problems
(See page DI±11).

A23669
EVAP Purge Flow:
Canister Purge VSV
(ON)
Vacuum Pump (OFF)Air Filter Fuel Tank fuel tank cap
To Intake Manifold
Pump Module
Pressure Sensor0.02 Inch Orifice
Vent Valve (OFF)
ECM
Soak Timer
Refueling Valve
To Atmosphere
DI±462
± DIAGNOSTICSENGINE
656 Author: Date:
2005 SEQUOIA (RM1146U)
Key±off monitor
This monitor checks for EVAP (Evaporative Emission) system leaks and pump module malfunctions. The
monitor starts 5 hours*
after the ignition switch is turned OFF. More than 5 hours are required to allow enough
time for the fuel to cool down to stabilize the Fuel Tank Pressure (FTP), thus making the EVAP system moni-
tor more accurate.
The electric vacuum pump creates negative pressure (vacuum) in the EVAP system and the pressure is
measured. Finally, the ECM monitors for leaks from the EVAP system, and malfunctions in both the pump
module and purge VSV, based on the EVAP pressure.
HINT:
*:If the engine coolant temperature is not below 35C 5 hours after the ignition switch is turned off, the moni-
tor check starts 2 hours later. If it is still not below 35C 7 hours after the ignition switch is turned off, the
monitor check starts 2.5 hours later.
Purge flow monitor
The purge flow monitor consists of the two monitors. The 1st monitor is always conducted every time and
the 2nd monitor is activated if necessary.

The 1st monitor
While the engine is running and the purge VSV (Vacuum Switching Valve) is ON (open), the ECM
monitors the purge flow by measuring the EVAP pressure change. If negative pressure is not
created, the ECM begins the 2nd monitor.

The 2nd monitor
The vent valve is turned ON (closed) and the EVAP pressure is then measured. If the variation
in the pressure is less than 0.5 kpa (3.75 mmHg), the ECM interprets this as the purge VSV being
stuck closed, and illuminates the MIL and sets DTC P0441 (2 trip detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before
and after conduction of the purge flow monitor, is measured by the ECM.