2001 TOYOTA SEQUOIA coolant

± DIAGNOSTICSENGINE
DI±187
381 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
Battery voltage8 V±
Throttle position learningCompleted
VVT systemNormal operate by scan±tool
Engine RPM400 to 5,700rpm
All of the following conditions are met:Condition 1 and 2
1. Engine coolant temperature±10C (14F)±
2. Either of the following conditions is met:Condition (a) or (b)
(a) Engine coolant temperature at engine
start±7C (19F)±
(b) Engine coolant temperature20C (68F)±
Fuel±cutOFF
Emission±related±misfire:
First 1,000 revolutions after engine start,
or check modeCrankshaft 1,000 revolutions
Except aboveCrankshaft 1,000 revolutions x 4
Catalyst±damage±misfire (MIL blinks):
All of the following conditions 1, 2 and 3
are metCrankshaft 200 revolutions
1. Driving cycle1st
2. Check modeOFF
3. Engine RPM±2,800 rpm
Except aboveCrankshaft 200 revolutions x 3
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Emission±related±misfire:
Misfire rate:1.2 % or more
Catalyst±damage±misfire (MIL blinks):
Number of misfire per 200 revolutions93 or more
(varies with intake air amount and RPM)
Multiple cylinders misfireDetected
MONITOR RESULT
Refer to page DI±26 for detailed information.
The test value and test limit information are described as shown in the following table. Check the monitor
result and test values after performing the monitor drive pattern (refer to ºConfirmation Monitorº).

MID (Monitor Identification Data) is assigned to each emissions±related component.

TID (Test Identification Data) is assigned to each test value.

Scaling is used to calculate the test value indicated on generic OBD ll scan tools.

± DIAGNOSTICSENGINE
DI±191
385 Author: Date:
2005 SEQUOIA (RM1146U)
HINT:
In order to memorize the DTC of misfire, it is necessary to drive around MISFIRE RPM, MISFIRE LOAD in
the DATA LIST for the following period of time. Take care not to turn the ignition switch OFF. Turning the
ignition switch OFF switches the diagnosis system from check mode to normal mode, and all DTCs, etc.,
are erased.
Engine SpeedTime
Idling3 minutes 30 seconds or more
1,000 rpm3 minutes or more
2,000 rpm1 minute 30 seconds or more
3,000 rpm1 minute or more
(f) Check if there is misfire, and the DTC and the freeze frame data. Record the DTC's, freeze frame data
and misfire counter data.
(g) Turn the ignition switch OFF and wait for at least 5 seconds.
INSPECTION PROCEDURE
HINT:

If DTCs besides misfire DTCs are memorized simultaneously, troubleshoot the non±misfire DTCs first.

If the misfire does not occur when the vehicle is brought to the workshop, the misfire can be confirmed
by reproducing the condition of the freeze frame data. Also, after finishing the repair, confirm that there
is no misfire (See confirmation driving pattern).

On 6 or 8 cylinder engines, misfiring cylinder identification is disabled at high engine speed and only
a general misfire fault code P0300 is stored instead of a cylinder specific misfire fault code (P0301 to
P0308).
If the misfire starts in a high engine speed area or the misfire occurs only in a high engine speed area,
only code P0300 may be stored.
When only a general misfire fault code like P0300 is stored:

Erase the general misfire fault code using the hand±held tester

Start the engine and drive the confirmation patten.

Read the value of the misfire ratio for each cylinder. Or read the DTC.

Repair the cylinder that has a high misfire ratio. Or repair the cylinder indicated by the DTC.

After finishing repairs, drive the confirmation pattern again and confirm that no misfire occurs.

When either of SHORT FT #1, LONG FT #1, SHORT FT #2 or LONG FT #2 in the freeze frame data
is over the range of ±20 %, there is a possibility that the air±fuel ratio is becoming RICH (±20 % or
less) or LEAN (+20 % or more).

When COOLANT TEMP in the freeze frame data is less than 80°C (176°F), there is a possibility of
misfire only during engine warm±up.

If the misfire cannot be reproduced, the following reasons may apply: 1) the vehicle has low fuel, 2)
improper fuel is being used, or 3) the ignition plug is contaminated.

Be sure to check the value on the misfire counter after the repair.

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).

A23648
GND 1V/ DIV KNK1 Signal Waveform
1 msec./ Division
± DIAGNOSTICSENGINE
DI±205
399 Author: Date:
2005 SEQUOIA (RM1146U)
Reference: Inspection using the oscilloscope.
The correct waveform is as shown.
ItemDetails
Terminal
KNK1 ± EKNK
or
KNK2 ± EKN2
Equipment Settings0.01 to 10 V/Division,
0.01 to 10 msec./Division
ConditionAfter warming up the engine,
keep the engine speed at 4,000 rpm.
MONITOR DESCRIPTION
The knock sensor located on the cylinder block detects spark knock.
When spark knock occurs, the sensor pick±up vibrates in a specific frequency range. When the ECM detects
the voltage in this frequency range, it retards the ignition timing to suppress the spark knock.
If there is a defect in the knock sensor or an open or short circuit, the voltage level will deviate outside the
normal operating range. The ECM interprets this deviation as a defect in the knock sensor and sets a DTC.
Example:
When the knock sensor voltage output is less than 0.5 V, or more than 4.5 V, and if either the condition contin-
ues for more than 3 sec.
MONITOR STRATEGY
P0325Knock sensor (Bank 1) range check (Chattering)
P0327Knock sensor (Bank 1) range check (Low volt-
age)
RltdDTC
P0328Knock sensor (Bank 1) range check (High volt-
age)
Related DTCsP0330Knock sensor (Bank 2) range check (Chattering)
P0327Knock sensor (Bank 2) range check (Low volt-
age)
P0328Knock sensor (Bank 2) range check (High volt-
age)
Main sensors/componentsKnock sensor
Required sensors/componentsRelated sensors/components
Crankshaft position sensor, Camshaft position
sensor, Engine coolant temperature sensor,
Mass air flow meter
Frequency of operationContinuous
Duration1 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
Battery voltage10.5 V±
Time after engine start5 sec.±

A21429
ECM
No.1 Ignition Coil with Igniter
No. 2 Ignition
Coil with Igniter Crankshaft
Position
Sensor
Camshaft
Position
Sensor
Other Sensors:
No. 3 Ignition
Coil with Igniter
No. 4 Ignition
Coil with Igniter
No. 5 Ignition
Coil with Igniter
No. 6 Ignition
Coil with Igniter
No. 7 Ignition
Coil with Igniter
No. 8 Ignition
Coil with Igniter
TA C
To TachometerFrom Battery
Igniter
Ignition CoilSpark Plug
No. 1 Cylinder
No. 4 Cylinder
No. 5 Cylinder
No. 6 Cylinder No. 2 Cylinder
No. 3 Cylinder
No. 7 Cylinder
No. 8 Cylinder IGT1
IGF1
IGT2
IGF2
IGT3
IGT4
IGT5
IGT6
IGT7
IGT8 (Engine Coolant Temp.
Sensor, Mass Air Flow
Sensor, Throttle Position
Sensor, etc.)
DI±222
± DIAGNOSTICSENGINE
416 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT DESCRIPTION
These DTCs indicate a malfunction related to primary circuit.
The DIS is a 1±cylinder ignition system which ignites one cylinder with one ignition coil. In the 1±cylinder
ignition system, the one spark plug is connected to the end of the secondary winding. High voltage generated
in the secondary winding is applied directly to the spark plug. The spark of the spark plug passes from the
center electrode to the ground electrode.
The ECM determines the ignition timing and outputs the ignition signals (IGTs) for each cylinder. Using the
IGT, the ECM turns on and off the power transistor inside the igniter and this switches on and off the current
to the primary coil. When the current to the primary coil is cut off, high±voltage is generated in the secondary
coil and this voltage is applied to the spark plugs to create sparks inside the cylinders. As the ECM cuts the
current to the primary coil, the igniter sends back the ignition confirmation signal (IGF) for each cylinder igni-
tion to the ECM.

B17432
Air PumpPressure
Sensor
Air
Air Injection
Driver (AID)
Air Switching Valve
(ASV)(EASV)Air Switching Valve No.2
(ASV No.2)(ASV1)VSV for Air Injection
Control
ECMEngine Coolant
Temp. Sensor
Mass Air Flow
Meter
Intake Air Temp.
Sensor To Bank 2To Bank1
Air Switching Valve No.2
(ASV No.2)(ASV2)
DI±234
± DIAGNOSTICSENGINE
428 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0412 Secondary Air Injection System Air Switch-
ing Valve ºAº Circuit
CIRCUIT DESCRIPTION
The secondary air injection system pumps air to the exhaust port to accelerate the activation of the catalyst.
The secondary air injection system consists of the ECM, air pump, Air Switching Valve (ASV) (EASV), Air
Switching Valve No.2 (ASV No.2) (ASV1, 2), pressure sensor and air injection driver (AID). The Air Switching
Valve (ASV)(EASV) is an electromagnetic type and Air Switching Valve No.2 (ASV No.2)(ASV1,2) is a vacu-
um type.
The secondary air injection system pumps pressurized air to the exhaust port by the air pump through the
ASV and ASV No.2. The ASV assists the ASV No.2. The ASV No.2 also controls air supply.
The ECM sends signals to the AID, and then the AID operates the air pump and ASV. The pressure sensor
detects pressure and exhaust pulsation in the system when the system operates and when it does not oper-
ate, and sends the data to the ECM.
DTC No.DTC Detection ConditionTrouble Area
P0412
All of the following conditions are met when engine is idling just
after cold start
(1 trip detection logic):
(a) Air injection system does not operate (Air pump OFF and all
ASVs OFF)
(b) Air injection driver diagnostic signal duty is 40%.
Open in air switching valve drive circuit

Short between air switching valve circuit and +B circuit

Air injection driver

Air switching valve

ECM
P0412
All of the following conditions are met when engine is idling just
after cold start
(1 trip detection logic):
(a) Air injection system operates (Air pump ON and all ASVs
ON)
(b) Air injection driver diagnostic signal duty is 40%.

Short between air switching valve circuit and body ground

Air injection driver

Air switching valve

ECM
DIDMV±01

DI±250
± DIAGNOSTICSENGINE
444 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR STRATEGY
RltdDTCP0420Bank 1 catalyst is deterioratedRelated DTCsP0430Bank 2 catalyst is deteriorated
Main sensors/componentsFront and rear heated oxygen sensor
Required sensors/componentsRelated sensors/components
Mass air flow meter, Engine coolant temperature
sensor, Engine speed sensor, Intake air tempera-
ture sensor
Frequency of operationOnce per driving cycle
Duration20 sec.
MIL operation2 driving cycles
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
Battery voltage11 V±
Intake air temperature±10C (14F)±
Engine coolant temperature75°C (167°F)±
Atmospheric pressure coefficient0.75±
IdleOFF
Engine RPM±3,200 rpm
A/F sensorActivated
Fuel system statusClosed loop
Engine load10 to 70 %
All of the following conditions are metCondition 1, 2 and 3
1. MAF6to 75 g/sec
2. Front catalyst temperature (estimated)620to 830C (1,148 to 1,526F)
3. Rear catalyst temperature (estimated)410 to 830C (770 to 1,526F)
Rear HO2S monitorCompleted
Shift position4th±
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Oxygen storage capacity (OSC) of catalystLess than 0.16

A23541
At least 3 minutes
2 seconds
Check
2 seconds
Engine Speed
3,000 rpm
2,000 rpm
Idling
Ignition Switch OFF(a)(b)(c) (d)
Time
Warming up(d)
± DIAGNOSTICSENGINE
DI±251
445 Author: Date:
2005 SEQUOIA (RM1146U)
MONITOR RESULT
Refer to page DI±26 for detailed information.
The test value and test limit information are described as shown in the following table. Check the monitor
result and test values after performing the monitor drive pattern (refer to ºConfirmation Monitorº).
MID (Monitor Identification Data) is assigned to each emissions±related component.
TID (Test Identification Data) is assigned to each test value.
Scaling is used to calculate the test value indicated on generic tools.
Catalyst bank 1 ± Active A/F control method
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$21$A9Multiply by 0.0003
(no dimension)Oxygen storage capacity of catalystMinimum test limit for catalystMaximum test limit for catalyst
Catalyst bank 2 ± Active A/F control method
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$22$A9Multiply by 0.0003
(no dimension)Oxygen storage capacity of catalystMinimum test limit for catalystMaximum test limit for catalyst
WAVEFORMS OF AIR±FUEL RATIO (A/F) AND HEATED OXYGEN (HO2) SEN-
SORS
HINT:
Perform the operation with the engine speeds and time durations described below prior to check the wave-
forms of the A/F and HO2 sensors. This is in order to activate the sensors sufficiently to obtain the appropri-
ate inspection results.
(a) Connect the hand±held tester to the DLC3.
(b) Start the engine and warm it up with all the accessories switched OFF, until the engine coolant temper-
ature stabilizes.
(c) Run the engine at an engine speed of between 2,500 rpm and 3,000 rpm for at least 3 minutes.
(d) After confirming that the waveform of the heated oxygen sensor (bank 1, 2 sensor 1 (HA1A, HA2A)),
oscillate around 0.5 V during feedback to the ECM, check the waveform of the heated oxygen sensor
(bank 1, 2 sensor 2 (OX1B, OX2B)).