Toyota Sequoia (2005). Manual - part 135

B17436

A23671

Port A

Port B

Air

A23672

Port A

Port B

Battery

Air

–

DIAGNOSTICS

ENGINE

DI–335

529

4

Check all air injection pipes and hoses of air injection system.

CHECK:
(a)

Remove the intake manifold (see page 

EM–36

).

(b)

Check all pipes and hoses of the air injection system.

OK:

All the air injection pipes and hoses are securely con-
nected.

CHECK:
(a)

Check all pipes and hoses of the air injection system for
blockage or damage.

OK:

The air injection system pipes and hoses have no
blockage or damage.

NG

Repair or replace pipe or hose.

OK

5

Check air switching valve operation.

PREPARATION:
(a)

Remove the intake manifold (see page 

EM–36

).

(b)

Remove the air switching valve.

CHECK:
Blow air into port A and check that air is not discharged from port
B.
OK:

Not discharged

CHECK:
(a)

Apply battery positive across the terminals.

(b)

Blow air into port A and check that air is discharged from
port B.

OK:

Discharged

NG

 Replace air switching valve and go to step 6.

OK

A16555

AIR INJ CHECK

AIR PUMP............................ON
EASV   ............................OPEN
ASV1.   .............................OPEN
ASV2...............................OPEN
A/F BANK1.......................19.05
A/F BANK2.........................14.5
PRESSURE....................17 kPa
PULSATION..............25.39 kPa
AI STATUS...........................OK
Remaining Time 05 sec.

Press [EXIT] to quit

DI–336

–

DIAGNOSTICS

ENGINE

530

6

Check air switching valve No.2 operation.

PREPARATION:
(a)

Start the engine and warm it up.

(b)

Turn the ignition switch to OFF.

(c)

Connect the hand–held tester to the DLC3.

(d)

Turn the ignition switch to ON and push the hand–held
tester main switch ON.

CHECK:
(a)

Select the following menu items: DIAGNOSIS/EN-
HANCED OBD II/SYSTEM CHECK/ AIR INJ CHECK/
MANUAL OPERATION/OPERATION 5 and 6

HINT:
OPERATION 5: AP:ON, EASV:OPEN, ASV1:OPEN,
ASV2:CLOSE
OPERATION 6: AP:ON, EASV:OPEN, ASV1:CLOSE,
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..
(b)

Read value of the A/F BANK1 and BANK2 on the hand–
held tester.

RESULT:

Air switching valve No.2 operation

Air–fuel ratio

Open

18 or more

Close

Approximately 14.5

HINT:

When the ASV No.2 operates normally, the A/F value is 18 or more when the valve is open, and approx-
imately 14.5 when the valve is closed.

Perform the following procedures only on the bank of which the valve is not open.

NEXT

A23560

Port A

–

DIAGNOSTICS

ENGINE

DI–337

531

7

Check VSV for air injection control operation.

PREPARATION:
(a)

Turn the ignition switch OFF.

(b)

Disconnect the vacuum hose from the VSV for air injec-
tion control.

(c)

Connect the hand–held tester to the DLC3.

(d)

Turn the ignition switch to ON and turn the tester ON.

CHECK:
(a)

When the air switching valve is operated using the hand–
held tester, check that negative pressure from the port A.

(b)

Select the following menu items: DIAGNOSIS/EN-
HANCED OBD II/SYSTEM CHECK/ AIR INJ CHECK/
MANUAL OPERATION/OPERATION 2

HINT:
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:

Negative pressure from port A

NG

Go to step 10.

OK

A23452

B17530

Port C

Port B

Port A

Air

B17531

Port C

Port B

Port A

Air

DI–338

–

DIAGNOSTICS

ENGINE

532

8

Check vacuum hose between air switching valve(s) No.2 and VSV for air injec-
tion control.

CHECK:
(a)

Check that the vacuum hoses between the air switching
valve(s) No.2 and VSV for air injection control are secure-
ly connected.

OK:

The vacuum hose(s) are securely connected.

CHECK:
(a)

Check the vacuum hoses for blockages and damage.

OK:

The vacuum hoses no blockages and damages.

NG

Repair or replace vacuum hose.

OK

9

Check air switching valve No.2 operation.

PREPARATION:
Remove the air switching valve No.2.
CHECK:
Blow air into port B and check that air is not discharged from the
port C.
OK:

Not discharged from port C

CHECK:
Apply vacuum 30 kPa (225 mmHg) to port A, blow air into port
B and check that air is discharged from the port C.
OK:

Discharged from port C

NG

Replace air switching valve No.2.

OK