Page 638 of 4323

B17444
Wire Harness Side:
Air Injection Driver Connector
A41
SIPSIV
DI±436
± DIAGNOSTICSENGINE
630 Author: Date:
2005 SEQUOIA (RM1146U)
9 Check voltage between SIV and SIP terminals of air injection driver and body
ground.
PREPARATION:
(a) Disconnect the A41 air injection driver connector.
(b) Connect the hand±held tester to the DLC3.
(c) Turn the ignition switch ON and turn the tester ON.
CHECK:
(a) When the air pump and air switching valve are operated
using the hand±held tester, measure the voltage between
terminals A41±3 (SIV) and A41±4 (SIP) of the air injection
driver connector and body ground.
(b) Select the following menu items: DIAGNOSIS/EN-
HANCED OBD II/SYSTEM CHECK/AIR INJ CHECK/
MANUAL OPERATION/OPERATION 1 and 2
HINT:
OPERATION 1: AP:OFF, EASV:CLOSE, ASV1:CLOSE,
ASV2:CLOSE
OPERATION 2: AP:ON, EASV:OPEN, ASV1:OPEN,
ASV2:OPEN
NOTICE:
This test only allows technicians to operate the AI system
for 5 seconds. Furthermore, the test can be performed 4
times a trip. If the test is repeated, intervals of at least 30
seconds are required between tests.
While the AI system operation using the hand±held tester
is prohibited, the tester displays the prohibition (WAIT or
ERROR). If the ERROR (AI STATUS NG) is displayed on the
tester, stop the engine for 10 minutes and then try again..
OK:
Standard:
Air pump operationTester ConnectionSpecified Condition
ONA41±3 (SIP) ± Body
ground10 V or more
OFFA41±3 (SIP) ± Body
ground3.5 to 7.7 V*
ASV operation (EASV)Tester ConnectionSpecified Condition
OPENA41±4 (SIV) ± Body
ground10 V or more
CLOSEA41±4 (SIV) ± Body
ground3.5 to 7.7 V*
*: 35 to 55 % of the +B voltage.
NG Repair or replace harness or connector be-
tween air injection driver and ECM.
OK
Page 639 of 4323

B17438
Wire Harness Side:
Air Pump Connector
A43
± DIAGNOSTICSENGINE
DI±437
631 Author: Date:
2005 SEQUOIA (RM1146U)
10 Check voltage between terminal 2 of air pump and body ground.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the A43 air pump connector.
(c) Connect the hand±held tester to the DLC3.
(d) Turn the ignition switch ON and turn the tester ON.
CHECK:
(a) When the air pump is operated using the hand±held tes-
ter, measure the voltage between terminal A43±2 of the
air injection driver connector and body ground.
(b) Select the following menu items: DIAGNOSIS/EN-
HANCED OBD II/SYSTEM CHECK/ AIR INJ CHECK/
MANUAL OPERATION/OPERATION 1 and 2
HINT:
OPERATION 1: AP:OFF, EASV:CLOSE, ASV1:CLOSE,
ASV2:CLOSE
OPERATION 2: AP:ON, EASV:OPEN, ASV1:OPEN,
ASV2:OPEN
NOTICE:
This test only allows technicians to operate the AI system
for 5 seconds. Furthermore, the test can be performed 4
times a trip. If the test is repeated, intervals of at least 30
seconds are required between tests.
While the AI system operation using the hand±held tester
is prohibited, the tester displays the prohibition (WAIT or
ERROR). If the ERROR (AI STATUS NG) is displayed on the
tester, stop the engine for 10 minutes and then try again..
OK:
Standard:
Air pump operationTester ConnectionSpecified Condition
ONA43±2 ± Body ground10 V or more
OFFA43±2 ± Body groundBelow 1.0 V
NG Go to step 14.
OK
Page 641 of 4323

A23475
Pressure GaugePressure Sensor
± DIAGNOSTICSENGINE
DI±439
633 Author: Date:
2005 SEQUOIA (RM1146U)
12 Check air pump operation.
PREPARATION:
(a) Connect the pressure gauge to the air switching valve as
shown in the illustration.
(b) Connect the hand±held tester to the DLC3.
(c) Turn the ignition switch ON and turn the tester ON.
CHECK:
(a) When the air pump is operated using the hand±held tes-
ter, measure the secondary air injection system pressure.
(b) Select the following menu items: DIAGNOSIS/EN-
HANCED OBD II/ACTIVE TEST/AIR INJ CHECK/MANU-
AL OPERATION/OPERATION 3
HINT:
OPERATION 2: AP:ON, EASV:CLOSE, ASV1:CLOSE,
ASV2:CLOSE
NOTICE:
This test only allows technicians to operate the AI system
for 5 seconds. Furthermore, the test can be performed 4
times a trip. If the test is repeated, intervals of at least 30
seconds are required between tests.
While the AI system operation using the hand±held tester
is prohibited, the tester displays the prohibition (WAIT or
ERROR). If the ERROR (AI STATUS NG) is displayed on the
tester, stop the engine for 10 minutes and then try again..
OK:
Standard:
25 to 30 kPa or more
NG Replace air pump.
OK
Page 642 of 4323
DI±440
± DIAGNOSTICSENGINE
634 Author: Date:
2005 SEQUOIA (RM1146U)
13 Check whether DTC output recurs.
PREPARATION:
(a) Start the engine and warm it up.
(b) Turn the ignition switch OFF.
(c) Connect a hand±held tester to the DLC3.
(d) Turn the ignition switch to ON and turn the tester ON.
(e) Clear the DTCs (see page DI±43).
(f) Start the engine.
CHECK:
(a) Perform SYSTEM CHECK to operate the air injection system.
Select the following menu items: DIAGNOSIS/ENHANCED OBD II/SYSTEM CHECK/AIR INJ
CHECK/AUTOMATIC OPERATION
(b) After operating secondary air injection system, confirm the pending codes of the secondary air injec-
tion system by selecting the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO /
PENDING CODES.
(c) Read DTC and check no DTC.
OK:
DTC P2444 or P2445 for the secondary air injection system is not output.
NG Check for intermittent problems
(See page DI±11).
OK
END
Page 645 of 4323

± DIAGNOSTICSENGINE
DI±443
637 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±
Ignition switchON
StarterOFF
EngineRunning
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Soak time measurement when ECM CPU clock counts 10
min.Less than 7 min., or more than 13 min.
INSPECTION PROCEDURE
HINT:
DTC P2610 is set if an internal ECM problem is detected. Diagnostic procedures are not required. ECM
replacement is required.
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 Replace ECM (See page SF±80).
NEXT
Check whether DTC output recurs.
(a) Connect a hand±held tester to the DLC3.
(b) Turn the ignition switch to ON.
(c) Clear DTCs (see page DI±43).
(d) Start the engine and wait for 10 minutes or more.
(e) On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PEND-
ING CODES.
(f) If no pending DTC is displayed, the repair has been successfully completed.
Page 654 of 4323

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
Page 656 of 4323

DI±454
± DIAGNOSTICSENGINE
648 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Hand±held tester only:
Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE
TEST. The A/F CONTROL function can help to determine whether the Air±Fuel Ratio (A/F) sensor, Heated
Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the A/F CONTROL operation using a hand±held tester.
(1) Connect a hand±held tester to the DLC3.
(2) Start the engine and turn the tester ON.
(3) Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
(4) On the tester, select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE
TEST / A/F CONTROL.
(5) 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).
(6) Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 (AFS B2S1) and OS2 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
Page 657 of 4323

+25 %
±12.5 %
More than 3.35 V
Less than 3.0 V
1
A/F Sensor (Sensor 1)
Output Voltage
Injection volume
Output voltage
HO2 Sensor (Sensor 2)
Output VoltageMain Suspected
Trouble Areas
OK
+25 %
±12.5 %
More than 3.35 V
Less than 3.0V
Injection volume
Output voltage
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
A/F sensor+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG OK
OK
OK
Almost
no reaction
'
Almost
no reaction Almost
no reaction
Almost
no reaction
Case
2
3
4
A/F sensor circuit A/F sensor heater
HO2 sensor
HO2 sensor circuit HO2 sensor heater
(Air±fuel ratio extremely
lean or rich)Injector
Gas leakage from
exhaust system Fuel pressure
± DIAGNOSTICSENGINE
DI±455
649 Author: Date:
2005 SEQUOIA (RM1146U)
NOTICE:
The Air±Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen (HO2)
sensor has a maximum output delay of approximately 20 seconds.
Following the A/F CONTROL procedure enables technicians to check and graph the voltage outputs
of both the A/F and HO2 sensors.
To display the graph, select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD
II / ACTIVE TEST / A/F CONTROL / USER DATA / AFS B1S1 and O2S B1S2, and press the YES but-
ton and then the ENTER button followed by the F4 button.
HINT:
DTC P2A00 may be also set, when the air±fuel ratio is stuck rich or lean.
A low A/F sensor voltage could be caused by a rich air±fuel mixture. Check for conditions that would
cause the engine to run rich.
A high A/F sensor voltage could be caused by a lean air±fuel mixture. Check for conditions that would
cause the engine to run lean.
Read freeze frame data using a hand±held tester or OBD II scan tool. 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.