Toyota Sequoia (2005). Manual - part 134

–

DIAGNOSTICS

ENGINE

DI–331

525

MONITOR STRATEGY

P1442

Air switching valve No. 2 (Bank 1) is stuck closed

Related DTCs

P1445

Air switching valve No. 2 (Bank 2) is stuck closed

Related DTCs

P2441

Air switching valve and air switching valve No.2

are stuck closed

Required sensors/components

Pressure sensor, Air switching valve No. 2 (Bank 1, 2), Electromagnetic air switching valve

Frequency of operation

Continuous

Duration

P1442 (Air switching valve No. 2 (Bank 1) is stuck closed): 20 sec.

P1445 (Air switching valve No. 2 (Bank 2) is stuck closed): 20 sec.

P2441 (Air switching valve is stuck closed): 8 sec.

MIL operation

2 driving cycles

Sequence of operation

None

TYPICAL ENABLING CONDITIONS

P1442, P1445: Air switching valve No. 2 bank 1 and/or bank 2 are stuck closed

It

Specification

Item

Minimum

Maximum

The monitor will run whenever this DTC is
not present

See page 

DI–18

Atmospheric pressure

76 kPa (570 mmHg)

–

Battery voltage

11.5 V

–

Idle

ON

Engine RPM

–

3,750 rpm

Time after secondary air injection out of

operation

10 sec.

–

Air injection pressure sensor fail

Not detected

P2441: Electromagnetic air switching valve is stuck closed or air switching valve No. 2 (Bank 1 and
Bank 2) are stuck closed

It

Specification

Item

Minimum

Maximum

The monitor will run whenever this DTC is
not present

See page 

DI–18

Atmospheric pressure

76 kPa (570 mmHg)

–

Battery voltage

11.5 V

–

Time after secondary air injection in op-

eration

6 sec.

–

AIR pump

ON

Air switching valve

ON

Air switching valve No. 2 (Bank 1)

ON

Air switching valve No. 2 (Bank 2)

ON

Engine RPM

–

3,750 rpm

Delay time after engine started

6 sec.

–

Air injection pressure sensor fail

Not detected

DI–332

–

DIAGNOSTICS

ENGINE

526

TYPICAL MALFUNCTION THRESHOLDS

P1442: Air switching valve No. 2 bank 1 is stuck closed

Detection Criteria

Threshold

Both of following conditions are met

Condition 1 and 2

1. Cumulative pressure pulsation

15 kPa (113 mmHg) or more

(when AI ON (Air pump ON, all of air switching valves are ON)

2. Air pressure change

Less than 1 kPa (7.5 mmHg)

(when opening air switching valve No. 2 (Bank 1))

P1445: Air switching valve No. 2 bank 2 is stuck closed

Detection Criteria

Threshold

Both of following conditions are met

Condition 1 and 2

1. Cumulative pressure pulsation

15 kPa (113 mmHg) or more

(when AI ON (Air pump ON, all of air switching valves are ON)

2. Air pressure change

Less than 1 kPa (7.5 mmHg)

(when opening air switching valve No. 2 (Bank 2))

P2441: Electromagnetic air switching valve is stuck closed or air switching valve No. 2 (Bank 1 and
Bank 2) are stuck closed

Cumulative pressure pulsation

Less than 15 kPa (113 mmHg)

(when AI ON (Air pump ON, all of air switching valves are ON)

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 ”Confirmation Monitor”).

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.

Secondary air injection (AIR) system

MID

TID

Scaling

Description of Test Value

Minimum Test Limit

Maximum Test Limit

$71

$E1

Multiply by 0.01

(g/s)

Test value of AIR amount insufficient

Minimum test limit

Maximum test limit

$71

$E2

Multiply by 0.01

(kPa)

Test value of AIR pump stuck ON

Minimum test limit

Maximum test limit

$71

$E3

Multiply by 0.01

(kPa)

Test value of AIR pump stuck OFF

Minimum test limit

Maximum test limit

$71

$E4

Multiply by 0.01

(kPa)

Test value of AIR control valve ON

Minimum test limit

Maximum test limit

$71

$E5

Multiply by 0.01

(kPa)

Test value of AIR control valve OFF

Minimum test limit

Maximum test limit

$71

$E6

Multiply by 0.01

(kPa)

Test value of AIR pressure change for

AIR valve

Minimum test limit

Maximum test limit

$71

$E7

Multiply by 0.01

(kPa)

Test value of AIR pressure change for

AIR VSV bank 1

Minimum test limit

Maximum test limit

$71

$E8

Multiply by 0.01

(kPa)

Test value of AIR pressure change for

AIR VSV bank 2

Minimum test limit

Maximum test limit

$71

$E9

Multiply by 0.01

(kPa)

Test value of AIR pressure pulsation for

AIR VSV when AIR pressure is low

Minimum test limit

Maximum test limit

B17426

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DIAGNOSTICS

ENGINE

DI–333

527

WIRING DIAGRAM

Refer to DTC P1441, P1444 and P2440 on page 

DI–314

.

INSPECTION PROCEDURE

1

Check any other DTCs output (In addition to secondary air injection system
DTCs).

PREPARATION:
(a)

Connect a hand–held tester to the DLC3.

(b)

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

(c)

Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

CHECK:
(a)

Read DTCs.

RESULT:

Display (DTC Output)

Proceed To

”P1442 and/or P1445” and P2441

A

P1442 and/or P1445

B

”P1442 and/or P1445 and/or P2441” and other DTCs

C

HINT:
If any DTCs other than P1441 and/or P1444 and P2440 are output, troubleshoot those DTCs first.

B

Go to step 6.

C

Go to DTC chart (See page 

DI–58

).

A

2

Check vacuum hose between throttle body and VSV for air injection control.

CHECK:
(a)

Check that the vacuum hoses between the throttle body
and VSV for air injection control are securely connected.

OK:

The vacuum hoses are securely connected.

CHECK:
(a)

Check the vacuum hoses for blockage or damage.

OK:

The vacuum hoses are no blockages and damage.

NG

Repair or replace vacuum hoses.

OK

B17440

A46

Air Switching Valve Connector

Wire Harness Side:

DI–334

–

DIAGNOSTICS

ENGINE

528

3

Check voltage between terminal 1 of air switching valve and body ground.

PREPARATION:
(a)

Remove the intake manifold (see page 

EM–36

).

(b)

Disconnect the A46 air switching valve 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 switching valve is operated using the hand–
held tester, measure voltage between terminal A46–1 of
the air switching valve 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 4

HINT:
OPERATION 1: AP:OFF, EASV:CLOSE, ASV1:CLOSE,
ASV2:CLOSE
OPERATION  4: AP:OFF,  EASV:OPEN, 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:

Tester operation

Tester Connection

Specified Condition

Operation 4

A46–1 – Body ground

10 V or more

Operation 1

A46–1 – Body ground

Below 1.0 V

NG

Go to step 12.

OK