B17434
Pressure Gauge
Pressure Sensor
± DIAGNOSTICSENGINE
DI±425
619 Author: Date:
2005 SEQUOIA (RM1146U)
2 Inspect pressure sensor.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Connect the pressure gauge to the pressure sensor as
shown in the illustration.
(c) Connect the hand±held tester to the DLC3 on the vehicle.
(d) Turn the ignition switch ON and push the hand±held tes-
ter main switch ON (Do not start engine).
(e) Select the following items: DIAGNOSIS / ENHANCED
OBD II / DATA LIST / 2ND AIR PRESS.
CHECK:
Check that the pressure displayed on the hand±held tester fluc-
tuates when applying the pressure to the pressure sensor with
the pressure gauge.
OK:
Pressure fluctuates in response to the pressure ap-
plied with pressure gauge.
NG Replace pressure sensor (See page EC±22).
OK
Replace ECM (See page SF±80).
DI±426
± DIAGNOSTICSENGINE
620 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P2444 Secondary Air Injection System Pump Stuck
ON Bank 1
DTC P2445 Secondary Air Injection System Pump Stuck
OFF Bank 1
CIRCUIT DESCRIPTION
Refer to DTC P0412 on page DI±234.
DTC No.DTC Detection ConditionTrouble Area
P2444
Air pump stuck ON.
The secondary air pressure is more than 5 kPa (38 mmHg)
despite the ECM ordering the air pump to turn off.
(2 trip detection logic)Short in air pump circuit
Air injection driver
Pressure sensor
Open or short in pressure sensor circuit
ECM
P2445
Air pump stuck OFF or air injection volume is insufficient.
The amount of air flow is below the criteria.
(The secondary air pressure is less than specified value de-
spite the ECM ordering the air pump turn ON.)
(2 trip detection logic)
Air pump fuse
Vacuum hose
Air pump assembly
Air injection driver
Open in air pump circuit
Air injection system piping
Pressure sensor
Open or short in pressure sensor circuit
ECM
MONITOR DESCRIPTION
P2444:
The ECM observes the pressure in the secondary air passage using the pressure sensor located on the air
switching valve in the secondary air injection system. The sensor measures the pressure in the secondary
air passage and sends a signal to the ECM.
If the pressure level from the sensor exceed a certain level despite the ECM turning off the air pump, the
ECM interprets this as a fault in the secondary air injection system and sets a DTC.
P2445:
The ECM calculates the amount of air flow in the secondary air system based on the output values of the
pressure sensor and mas air flow meter.
The ECM determines whether the amount of air flow is normal or not according to the calculated value. When
the amount of air flow is below the criteria, the ECM stores the DTC and illuminates the MIL.
DIDMU±01
B17434
Pressure GaugePressure Sensor
B17436
± DIAGNOSTICSENGINE
DI±433
627 Author: Date:
2005 SEQUOIA (RM1146U)
5 Inspect ECM (air voltage).
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Connect the pressure gauge to the pressure sensor as
shown in the illustration.
(c) Connect the hand±held tester to the DLC3 on the vehicle.
(d) Turn the ignition switch ON and push the hand±held tes-
ter main switch ON (Do not start engine).
(e) Select the following items: DIAGNOSIS / ENHANCED
OBD II / DATA LIST / AIR PUMP PRS.
CHECK:
Check that the pressure displayed on the hand±held tester fluc-
tuates when applying the pressure to the pressure sensor with
the pressure gauge.
OK:
Pressure fluctuates in response to the pressure ap-
plied with the pressure gauge.
NG Replace pressure sensor.
OK
6 Check connection of all air injection system piping and hoses.
CHECK:
(a) Remove the intake manifold (see page EM±36).
(b) Check that all the pipes and hoses between the air pump
and air switching valve are securely connected.
OK:
All the air injection pipes and hoses are securely con-
nected.
CHECK:
(a) Check the pipe and hoses for blockage or damage.
OK:
The air injection system pipes and hoses have no
blockage and damage.
NG Repair or replace air injection system piping.
OK
A23458
Air±fuel Ratio Sensor Output:
Active A/F Control
A/F Sensor Output
Fuel Injection VolumeON
OFF
NormalMalfunction 10 Seconds
± DIAGNOSTICSENGINE
DI±451
645 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P2A00 A/F Sensor Circuit Slow Response (Bank 1
Sensor 1)
DTC P2A03 A/F Sensor Circuit Slow Response (Bank 2
Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P2195 on page DI±383.
DTC No.DTC Detection ConditionsTrouble Areas
P2A00
P2A03Calculated test value for A/F sensor response rate deteriora-
tion level is less than threshold.Open or short in A/F sensor (sensor 1) circuit
A/F sensor (sensor 1)
ECM
MONITOR DESCRIPTION
After engine is warmed up, the ECM performs air±fuel ratio feedback control to regulate the air±fuel ratio
at stoichiometric ratio. In addition, this vehicle performs Active A/F Ratio Control for approximately 10 se-
conds after preconditions met in order to measure the A/F sensor response rate. During active air±fuel ratio
control, the ECM forcibly increases and decreases the injection volume for certain amount based on learned
stoichiomentric air ±fuel ratio during usual air±fuel feedback control, and measures the A/F sensor response
rate. The ECM calculates the signal from the A/F sensor while value for A/F sensor response rate deteriora-
tion level.
If the test value for A/F sensor response rate deterioration level is less than threshold, ECM interprets this
as a malfunction, and sets the DTC.
DIDFY±01
Vehicle speed
(40 ±120 km/h)25 ± 75mph)
(g)(h)
Warm up
3 minutes DI±452
± DIAGNOSTICSENGINE
646 Author: Date:
2005 SEQUOIA (RM1146U)
CONFIRMATION DRIVING PATTERN
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the hand±held tester ON.
(d) Clear DTCs.
(e) Select the following menu items: DIAGNOSIS/ENHANCED OBD II/MONITOR INFO/MONITOR RE-
SULT.
(f) Check that RES RATE B1 S1 is INCOMPL.
(g) Start the engine and warm it up.
(h) Drive the vehicle at between 25 mph and 75 mph (40 km/h and 120km/h) for 3 minutes. However, the
vehicle should be driven at constant±speed.
(i) When detection is complete, Response rate of MONITOR RESULT changes.
If the value does not change, perform step (g) once more.
(j) Notes the value of the Monitor Result.
(k) Select the following menu items: DIAGNOSIS/ENHANCED OBD II/DTC INFO/ PENDING CODES.
(l) Check if any DTCs (any pending DTCs) are set.
MONITOR STRATEGY
RltdDTCP2A00A/F sensor (Bank 1) slow responseRelated DTCsP2A03A/F sensor (Bank 2) slow response
Required sensors/componentsA/F sensor
Frequency of operationOnce per driving cycle
Duration10 to 15 sec.
MIL operation2 driving cycles
Sequence of operationNone
± DIAGNOSTICSENGINE
DI±453
647 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever these
DTCs are not presentSee page DI±18
Battery voltage11 V±
ECT75°C (167°F)±
IdleOFF
Engine RPM±4,000 rpm
A/F sensor statusActivated
Fuel cutOFF
Engine load10 to 70%
Estimated catalyst temperature500 to 800°C (932 to 1,472°F)
Shift position2nd±
Catalyst monitorNot executing
Intake air amount2.5 to 12 g/sec
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Response rate deterioration levelLess than 0.2 V
Number of average5 or more
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.
A/F sensor bank 1 sensor 1
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$01$8EMultiply by 0.0003
(no dimension)Response rate deterioration level for
A/F sensorMalfunction criterionFF
A/F sensor bank 2 sensor 1
MIDTIDScalingDescription of Test ValueMinimum Test LimitMaximum Test Limit
$05$8EMultiply by 0.0003
(no dimension)Response rate deterioration level for
A/F sensorMalfunction criterionFF
WIRING DIAGRAM
Refer to DTC P2195 on page DI±383.
0.02 inch orifice clogged
Pressure sensor low outputP043E
P043FP0441 P0451 P0452 P0453 P0455 P0456 P2419P2401
P2402
0.02 inch orifice high±flow
Pressure sensor stuck
Pressure sensor noise
Gross leak
Small leak
Vacuum pump stuck OFF
Vacuum pump stuck ON
Vent valve stuck closed
Vent valve stuck open (vent) Purge VSV stuck open
Purge VSV stuck closed
Pressure sensor high output
DTCs
Malfunctioning AreasP2420 P0450
DI±460
± DIAGNOSTICSENGINE
654 Author: Date:
2005 SEQUOIA (RM1146U)
EVAP (Evaporative Emission) Inspection Procedure
DTCS RELATING TO EVAP SYSTEM
DTCsMonitoring ItemsSee Page
P043E0.02 inch orifice clogged (built into pump module)DI±445
P043F0.02 inch orifice high±flow (built into pump module)DI±445
P0441
Purge VSV (Vacuum Switching Valve) stuck closed
Purge VSV stuck open
Purge flow
DI±257
P0450Pressure sensor (built into pump module) voltage abnormal fluctuationDI±264
P0451Pressure sensor (built into pump module) noising
Pressure sensor stuck (built into pump module)DI±264
P0452Pressure sensor (built into pump module) voltage lowDI±264
P0453Pressure sensor (built into pump module) voltage highDI±264
P0455EVAP gross leakDI±273
P0456EVAP small leakDI±273
P2401Vacuum pump stuck OFF (built into pump module)DI±410
P2402Vacuum pump stuck ON (built into pump module)DI±410
P2419Vent valve stuck closed (built into pump module)DI±416
P2420Vent valve stuck open (vent) (built into pump module)DI±416
P2610Soak timer (built into ECM)DI±442
If any EVAP system DTCs are set, the malfunctioning area can be determined using the table below.
NOTICE:
If the 0.02 inch reference pressure difference between the first and second checks is greater than
the specification, the DTCs corresponding to the reference pressure (P043E, P043F, P0441, P0455,
P0456, P2401, P2420) will be all stored.
DIDFZ±01
0.02 inch orifice clogged
Pressure sensor voltage lowP043E
P043FP0441 P0451 P0452 P0453 P0455 P0456 P2419P2401
P2402
0.02 inch orifice high±flow
Pressure sensor stuck
Pressure sensor noising
Gross leak
Small leak
Vacuum pump stuck OFF
Vacuum pump stuck ON
Vent valve stuck ON (closed)
Vent valve stuck OFF (vent) Purge VSV stuck open
Purge VSV stuck closed
Pressure sensor voltage high
DTCs
Malfunctioning AreasP2420P0450
DI±466
± DIAGNOSTICSENGINE
660 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
NOTICE:
A hand±held tester is required to conduct the following diagnostic troubleshooting procedure.
HINT:
Using hand±held tester monitor results enables the EVAP (Evaporative Emission) system to be con-
firmed.
Read freeze frame data using a hand±held tester Freeze frame data record the engine condition when
malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle
was moving or stationary, if the engine was warmed up or not, if the air±fuel ratio was lean or rich, and
other data, from the time the malfunction occurred.
1 Confirm DTC.
(a) Turn the ignition switch to OFF and wait for 10 seconds.
(b) Turn the ignition switch to ON.
(c) Turn the ignition switch to OFF and wait for 10 seconds.
(d) Connect a hand±held tester to the DLC3.
(e) Turn the ignition switch to ON and turn the tester ON.
(f) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
(g) Confirm DTCs and freeze frame data.
If any EVAP system DTCs are set, the malfunctioning area can be determined using the table below.
NOTICE:
If the 0.02 inch reference pressure difference between the first and second checks is greater than
the specification, the DTCs corresponding to the reference pressure (P043E, P043F, P0441, P0455,
P0456, P2401, P2420) will be all stored.
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