Toyota Sequoia (2005). Manual - part 158

–

DIAGNOSTICS

ENGINE

DI–427

621

MONITOR STRATEGY

P2444

Air pump is stuck ON

R l t d DTC

Air pump is stuck OFF

Related DTCs

P2445

Air flow volume is insufficient

P2445

Air pressure sensor is stuck

Required sensors/components

AIR pump, AIR pressure sensor

Frequency of operation

Continuous

Duration

P2444 (Air pump is stuck ON): 20 sec.

P2445 (Air pump is stuck OFF): 8 sec.

P2445 (Air flow volume is insufficient): 8 sec.

P2445 (Air pressure sensor is stuck:) 1.5 sec.

MIL operation

2 driving cycles

Sequence of operation

None

TYPICAL ENABLING CONDITIONS

P2444: Air pump is stuck ON

It

Specification

Item

Minimum

Maximum

The monitor will run whenever this DTC is
not present

See page 

DI–18

Atmospheric pressure

570 mmHg (76 kPa)

–

Battery voltage

11.5 V

–

Time after secondary air injection out of

operation

10 sec.

–

AIR pump

OFF

Air switching valve No. 2 (Bank 1)

OFF

Air switching valve No. 2 (Bank 2)

OFF

Engine RPM

–

3,750 rpm

Air injection pressure sensor fail

Not detected

P2445: Air pump is stuck OFF or air insufficient

It

Specification

Item

Minimum

Maximum

The monitor will run whenever this DTC is
not present

See page 

DI–18

Atmospheric pressure

570 mmHg (76 kPa)

–

Battery voltage

11.5 V

–

Time after secondary air injection out of

operation

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–428

–

DIAGNOSTICS

ENGINE

622

P2445: Air pressure sensor is stuck

It

Specification

Item

Minimum

Maximum

The monitor will run whenever this DTC is
not present

See page 

DI–18

ECT at engine start

–

5

°

C (41

°

F)

IAT at engine start

–15

°

C (5

°

F)

–

Time that ECT is 80

°

C (176

°

F) or higher

10 to 60 min.

Cumulative intake air amount

172 g

–

One of the following conditions is met

Condition 1, 2 or 3

1. Vehicle speed

80 km/h (49.7 mile)

–

2. Engine RPM

0 rpm

–

3. Throttle position

0 deg

Air switching valve

OFF

Air switching valve No. 2 (Bank 1)

OFF

Air switching valve No. 2 (Bank 2)

OFF

Air injection pressure sensor fail

Not detected

TYPICAL MALFUNCTION THRESHOLDS

P2444: Air pump is stuck ON

Detection Criteria

Threshold

Smoothed pressure

5 kPa (113 mmHg) or more

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

P2445: Air pump is stuck OFF or air insufficient

Detection Criteria

Threshold

Either of the following conditions is met

Condition 1 or 2

1. Air flow value

100 L/min. or less

2. Smoothed pressure

Less than 1 kPa (7.5 mmHg)

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

P2445: Air pressure sensor is stuck

Detection Criteria

Threshold

Detected times of identifying condition 1 is met

4 times or more

Air pressure change

5 kPa (113 mmHg) or more

–

DIAGNOSTICS

ENGINE

DI–429

623

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

WIRING DIAGRAM

Refer to DTC P0412 on page 

DI–234

.

DI–430

–

DIAGNOSTICS

ENGINE

624

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

P2445

A

P2444

B

P2444 and P2445

B

”P2444 and P2445” and other DTCs

C

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