2001 TOYOTA SEQUOIA Page 18

DI±430
± DIAGNOSTICSENGINE
624 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
To check the pressure condition in the secondary air passage, the hand±held tester is available.
1 Is the DTC P2444 and/or P2445 being output?
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main switch ON.
(c) Select the following items: DIAGNOSIS/ENHANCED OBD II/DTC INFO/CURRENT CODES.
CHECK:
Read the DTCs.
RESULT:
Display (DTC output)Proceed to
P2445A
P2444B
P2444 and P2445B
ºP2444 and P2445º and other DTCsC
HINT:
If any other codes besides P2444 or P2445 is output, perform troubleshooting for those DTCs first.
B Go to step 7.
C Go to DTC chart (See page DI±58).
A

B17435Vacuum Hose
DI±432
± DIAGNOSTICSENGINE
626 Author: Date:
2005 SEQUOIA (RM1146U)
3 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 the secondary air injection system, confirm the pending codes for the secondary air
injection system by selecting the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO
/ PENDING CODES.
(c) Read DTCs and check that no DTC is set.
OK:
DTC P2444 or P2445 for the secondary air injection system is not output.
NG Go to step 4.
OK
Check for intermittent problems
(See page DI±11).
4 Check vacuum hose.
CHECK:
(a) Remove the intake manifold (see page EM±36).
(b) Check the vacuum hose connection between the pres-
sure sensor and air switching valve.
OK:
The vacuum hose is securely connected.
CHECK:
(a) Check the vacuum hose for blockage or damage.
OK:
The vacuum hose has no blockage or damage.
NG Repair or replace vacuum hose.
OK

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

B17444
Wire Harness Side:
Air Injection Driver Connector
A41
+B
E
B17443
Wire Harness Side:
Air Injection Driver Connector
A40
BATT
DI±434
± DIAGNOSTICSENGINE
628 Author: Date:
2005 SEQUOIA (RM1146U)
7 Inspect air injection driver power source circuit.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the A40 and A41 air injection driver connec-
tors.
(c) Turn the ignition switch to ON.
CHECK:
Measure the voltage between terminals A41±5 (+B) and A40±1
(BATT) of the air injection driver and body ground.
OK:
Standard:
Tester ConnectionSpecified Condition
A41±5 (+B) ± Body ground10 V or more
A40±1 (BATT) ± Body ground10 V or more
CHECK:
Measure the resistance between terminal A41±1 (E) of the air
injection driver and body ground.
OK:
Standard:
Tester ConnectionSpecified Condition
A41±1 (E) ± Body groundBelow 1 W
NG Repair or replace harness or connector.
OK

B17411
E4
AIRVAIRP
± DIAGNOSTICSENGINE
DI±435
629 Author: Date:
2005 SEQUOIA (RM1146U)
8 Check voltage between AIRP and AIRV terminal of ECM and body ground.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) 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 E4±25 (AIRP) and E4±4 (AIRV) of the air injec-
tion 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
ONE4±25 (AIRP) ±
Body ground10 V or more
OFFE4±25 (AIRP) ±
Body ground3.5 to 7.7 V*
ASV operation (EASV)Tester ConnectionSpecified Condition
OPENE4±4 (AIRV) ±
Body ground10 V or more
CLOSEE4±4 (AIRV) ±
Body ground3.5 to 7.7 V*
*: 35 to 55 % of the +B voltage.
NG Replace ECM (See page SF±80).
OK

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

B17438
Wire Harness Side:
Air Pump Connector
A43
DI±438
± DIAGNOSTICSENGINE
632 Author: Date:
2005 SEQUOIA (RM1146U)
11 Check for open in harness and connector between air pump and body ground.
PREPARATION:
(a) Remove the intake manifold (see page EM±36).
(b) Disconnect the A43 air pump connector.
CHECK:
Check the resistance between the wire harness side connec-
tors and body ground.
OK:
Standard:
Tester ConnectionSpecified Condition
A43±1 ± Body groundBelow 1 W
NG Repair or replace harness or connector.
OK

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