Toyota Sequoia (2005). Manual - part 118

–

DIAGNOSTICS

ENGINE

DI–267

461

Pressure sensor chattering, low/high voltage:

Battery voltage

8 V

–

Ignition switch

ON

Starter

OFF

TYPICAL MALFUNCTION THRESHOLDS

Detection Criteria

Threshold

Pressure sensor noise:

Frequency that FTP change is 0.3 kPa or more

10 times or more for 10 sec.

Pressure sensor stuck:

FTP change for 10 sec. during EVAP monitor (0.02 inch

reference pressure)

Less than 4.9 mmHg (0.65 kPa)

Pressure sensor chattering:

Pressure sensor voltage

Less than 0.45 V, or more than 4.9 V

Pressure sensor low voltage:

Pressure sensor voltage

Less than 0.45 V

Pressure sensor high voltage:

Pressure sensor voltage

More than 4.9 V

DI–268

–

DIAGNOSTICS

ENGINE

462

INSPECTION PROCEDURE

NOTICE:

When a vehicle is brought into the workshop, leave it as it is. Do not change the vehicle condi-
tion. For example, do not tighten the fuel tank cap.

Do not disassemble the pump module.

A hand–held tester is required to conduct the following diagnostic troubleshooting procedure.

1

Confirm DTC and EVAP pressure.

PREPARATION:
(a)

Connect a hand–held tester to the DLC3.

(b)

Turn the ignition switch to ON (do not start the engine).

(c)

Turn the tester ON.

CHECK:
(a)

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

(b)

Read DTCs.

(c)

Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / VAPOR
PRESS.

(d)

Read the EVAP (Evaporative Emission) pressure displayed on the tester.

RESULT:

Display (DTC Output)

Test Results

Suspected Trouble Areas

Proceed To

P0451



Pressure sensor

C

P0452

Less than 45 kpa (430 mmHg)

Wire harness/connector (ECM – pressure
sensor)

Pressure sensor

Short in ECM circuit

A

P0453

More than 120 kPa (900 mmHg)

Wire harness/connector (ECM – pressure
sensor)

Pressure sensor

Open in ECM circuit

B

B

Go to step 4.

C

 Go to EVAP inspection procedure 
(See page 

DI–460

).

A

B17417

E4

PPMP

–

DIAGNOSTICS

ENGINE

DI–269

463

2

Measure resistance between terminal PPMP of ECM and body ground.

PREPARATION:
(a)

Turn the ignition switch to OFF.

(b)

Disconnect the E4 ECM connector.

CHECK:
Measure the resistance between PPMP terminal of the ECM
connector and the body ground.

RESULT:

Test Results

Suspected Trouble Areas

Proceed To

10 

Ω

 or less

Wire harness/connector (ECM – pressure sensor)

Short in pressure sensor circuit

A

10 k

Ω

 or more

Wire harness/connector (ECM – pressure sensor)

Short in ECM circuit

B

B

Go to step 7.

A

B17417

E4

PPMP

A23446

L5

DI–270

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DIAGNOSTICS

ENGINE

464

3

Measure resistance between terminal PPMP of ECM and body ground.

PREPARATION:
(a)

Disconnect the L5 canister connector.

(b)

Disconnect the E4 ECM connector.

CHECK:
Check the resistance between PPMP terminal of the ECM con-
nector and the body ground.

Result:

Test Results

Suspected Trouble Areas

Proceed To

10 k

Ω

 or more

Short in pressure sensor circuit

A

10 

Ω

 or less

Short in wire harness/connector (ECM – pressure sensor)

B

A

Go to step 5.

B

Go to step 6.