Toyota FJ Cruiser (GSJ 10, 15 series). Instruction - part 72

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES–243

ES

HINT:
If no pending DTCs are displayed on the tester, the 
repair has been successfully completed.

NEXT

COMPLETED

ES–244

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES

DTC SUMMARY

DESCRIPTION

The description can be found in the EVAP (Evaporative Emission) System (See page 

ES-352

).

INSPECTION PROCEDURE

Refer to the EVAP System (See page 

ES-357

).

MONITOR DESCRIPTION

5 hours

*

 after the ignition switch is turned to OFF, the leak detection pump creates negative pressure 

(vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP 
pressure.
HINT:

*

: If the engine coolant temperature is not below 35

°C (95°F) 5 hours after the ignition switch is turned to 

OFF, the monitor check starts 2 hours later. If it is still not below 35

°C (95°F) 7 hours after the ignition 

switch is turned to OFF, the monitor check starts 2.5 hours later.

DTC

P0455

Evaporative Emission Control System Leak 
Detected (Gross Leak)

DTC

P0456

Evaporative Emission Control System Leak 
Detected (Very Small Leak)

DTCs

Monitoring Items

Malfunction Detection Conditions

Trouble Areas

Detection 

Timings

Detection 

Logic

P0455

EVAP gross leak

Leak detection pump creates negative 
pressure (vacuum) in EVAP system and 
EVAP system pressure measured. 
Reference pressure measured at start 
and at end of leak check.
If stabilized pressure higher than [second 
reference pressure x 0.2], ECM 
determines that EVAP system has large 
leak.

•

Fuel cap (loose)

•

Leakage from EVAP line
(Canister - Fuel tank)

•

Leakage from EVAP line
(Purge VSV - Canister)

•

Canister pump module

•

Leakage from fuel tank

•

Leakage from canister

While ignition 
switch OFF

2 trip

P0456

EVAP small leak

Leak detection pump creates negative 
pressure (vacuum) in EVAP system and 
EVAP system pressure measured. 
Reference pressure measured at start 
and at end of leak check.
If stabilized pressure higher than second 
reference pressure, ECM determines 
that EVAP system has small leak.

•

Fuel cap (loose)

•

Leakage from EVAP line
(Canister - Fuel tank)

•

Leakage from EVAP line
(Purge VSV - Canister)

•

Canister pump module

•

Leakage from fuel tank

•

Leakage from canister

While ignition 
switch OFF

2 trip

Sequ

ence

Operations

Descriptions

Duration

-

ECM activation

Activated by soak timer, 5 hours (7 or 9.5 hours) after ignition switch turned to OFF.

-

A

Atmospheric pressure 
measurement

Vent valve turned OFF (vent) and EVAP system pressure measured by ECM in order to 
register atmospheric pressure.
If pressure in EVAP system not between 70 kPa-a and 110 kPa-a (525 mmHg-a and 825 
mmHg-a), ECM cancels EVAP system monitor.

10 seconds

B

First reference 
pressure measurement

In order to determine reference pressure, leak detection pump creates negative pressure 
(vacuum) through reference orifice and then ECM checks if leak detection pump and vent 
valve operate normally.

60 seconds

1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES–245

ES

*

 If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.

(a) P0455: EVAP gross leak
In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system and the 
EVAP system pressure is measured. If the stabilized system pressure is higher than [second reference 
pressure x 0.2] (near atmospheric pressure), the ECM determines that the EVAP system has a large 
leakage, illuminates the MIL and sets the DTC (2 trip detection logic).

C

EVAP system pressure 
measurement

Vent valve turned ON (closed) to shut EVAP system.
Negative pressure (vacuum) created in EVAP system, and EVAP system pressure then 
measured.
Write down measured value as will be used in leak check.
If EVAP pressure does not stabilize within 15 minutes, ECM cancels EVAP system monitor.

15 minutes

*

D

Purge VSV monitor

Purge VSV opened and then EVAP system pressure measured by ECM.
Large increase indicates normality.

10 seconds

E

Second reference 
pressure measurement

After second reference pressure measurement, leak check performed by comparing first and 
second reference pressure.
If stabilized system pressure higher than second reference pressure, ECM determines that 
EVAP system leaking.

60 seconds

F

Final check

Atmospheric pressure measured and then monitoring result recorded by ECM.

-

Sequ

ence

Operations

Descriptions

Duration

Operation A: Atmospheric Pressure Measurement

Operation C: EVAP System Pressure Measurement

Operation B, E:

Reference Pressure Measurement

Operation D: Purge VSV Monitor

Purge VSV: OFF

Canister

Fuel Tank

Vent Valve: OFF (vent)

Canister Pump Module

Canister Filter

Canister 
Pressure 
Sensor

Leak Detection Pump: OFF

OFF

ON

ON (closed)

Atmospheric 
Pressure

Negative 
Pressure

OFF

OFF (vent)

ON

Reference Orifice (0.02 Inch)

ON

ON

ON (closed)

A112612E01

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1GR-FE ENGINE CONTROL SYSTEM  –  SFI SYSTEM

ES

(b) P0456: EVAP very small leak
In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system and the 
EVAP system pressure is measured. If the stabilized system pressure is higher than the second reference 
pressure, the ECM determines that the EVAP system has a small leakage, illuminates the MIL and sets 
the DTC (2 trip detection logic).

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

Required Sensors/Components

Purge VSV and canister pump module

Frequency of Operation

Once per driving cycle

Duration

Within 15 minutes (varies with amount of fuel in tank)

MIL Operation

2 driving cycles

Sequence of Operation

None

Monitor runs whenever following DTCs not present

None

EVAP key-off monitor runs when all of following conditions met

-

Atmospheric pressure

70 to 110 kPa-a (525 to 825 mmHg-a)

Battery voltage

10.5 V or more

Vehicle speed

Below 2.5 mph (4 km/h)

Ignition switch

OFF

Time after key off

5 or 7 or 9.5 hours

Canister pressure sensor malfunction (P0450, P0451, P0452 and 
P0453)

Not detected

Purge VSV

Not operated by scan tool

Vent valve

Not operated by scan tool

EVAP Pressure when EVAP System Leaks:

Purge VSV

Vent Valve

Leak Dtection 
Pump

EVAP Pressure

Positive

Negative

First Reference 
Pressure

Sequence

10 seconds

60 
seconds

60 
seconds

10 
seconds

P0455

ON: Open

ON: Closed

OFF: Closed

OFF: Vent

P0456

Time

OK

A

B

C

D

E

ON

ON

ON

Within 15 minutes

[Second 
Reference 
Pressure] x 0.2

[Second 
Reference 
Pressure]

A106061E05