Toyota Tundra. Manual — part 1211

Typical Malfunction Thresholds

TYPICAL MALFUNCTION THRESHOLDS

MONITOR RESULT

Refer to CHECKING MONITOR STATUS .

DTC P0451 EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE SENSOR
RANGE/PERFORMANCE; DTC P0452 EVAPORATIVE EMISSION CONTROL SYSTEM
PRESSURE SENSOR/SWITCH LOW INPUT; DTC P0453 EVAPORATIVE EMISSION CONTROL
SYSTEM PRESSURE SENSOR/SWITCH HIGH INPUT

DTC SUMMARY

DTC SUMMARY CHART

Purge duty cycle

8% or more

Both of following conditions met

Conditions 1 and 2

1. EVAP pressure change when purge operation started

Less than 0.1 kPa-g (0.75 mmHg-
g)

2. EVAP pressure change during purge operation when vent valve
closed

Less than 0.5 kPa-g (3.75 mmHg-
g)

DTC

Monitoring

Item

Malfunction

Detection

Condition

Trouble Area

Detection Timing

Detection

Logic

P0451

Canister
pressure sensor
noise

Sensor output
voltage fluctuates
frequently within
certain time
period.



Canister pump module



Connector/wire harness
(Canister pump module
- ECM)



EVAP system hose
(pipe from air inlet port
to canister pump
module, canister filter,
fuel tank vent hose)



ECM



EVAP
monitoring
(ignition
switch OFF)



Engine
running

2 trip

Canister
pressure sensor
signal becomes
fixed/flat

Sensor output
voltage does not
vary within certain
time period.



Canister pump module



Connector/wire harness
(Canister pump module
- ECM)



EVAP system hose
(pipe from air inlet port
to canister pump
module, canister filter,
fuel tank vent hose)



EVAP
monitoring
(ignition
switch OFF)

2 trip

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

HINT:

The canister pressure sensor is built into the canister pump module.

DESCRIPTION

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

MONITOR DESCRIPTION



ECM

P0452

Canister
pressure sensor
low input

EVAP pressure
less than 42.1 kPa
for 0.5 seconds.



Canister pump module



Connector/wire harness
(Canister pump module
- ECM)



EVAP system hose
(pipe from air inlet port
to canister pump
module, canister filter,
fuel tank vent hose)



ECM



Ignition
switch ON



EVAP
monitoring
(ignition
switch OFF)

1 trip

P0453

Canister
pressure sensor
high input

EVAP pressure
more than 123.8
kPa for 0.5
seconds.



Canister pump module



Connector/wire harness
(Canister pump module
- ECM)



EVAP system hose
(pipe from air inlet port
to canister pump
module, canister filter,
fuel tank vent hose)



ECM



Ignition
switch ON



EVAP
monitoring
(ignition
switch OFF)

1 trip

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

Fig. 155: Monitor Description - Canister Pressure Graph

1. DTC P0451: Canister pressure sensor noise or fixed/flat

If the canister pressure sensor voltage output fluctuates rapidly for 10 seconds, the ECM stops the EVAP
system monitor. The ECM interprets this as noise from the canister pressure sensor, and stops the EVAP
system monitor. The ECM then illuminates the MIL and sets the DTC. Alternatively, if the sensor voltage
output does not change for 10 seconds, the ECM interprets this as the sensor being fixed/flat, and stops
the monitor. The ECM then illuminates the MIL and sets the DTC. (Both malfunctions are detected by 2
trip detection logic.)

2. DTC P0452: Canister pressure sensor voltage low

If the canister pressure sensor voltage output [pressure] is below 0.45 V [42.1 kPa-a (315.9 mmHg-a)],
the ECM interprets this as an open or short circuit malfunction in the canister pressure sensor or its
circuit, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC (1 trip
detection logic).

3. DTC P0453: Canister pressure sensor voltage high

If the canister pressure sensor voltage output [pressure] is 4.9 V [123.8 kPa-a (928.4 mmHg-a)] or more,
the ECM interprets this as an open or short circuit malfunction in the canister pressure sensor or its
circuit, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC (1 trip
detection logic).

MONITOR STRATEGY

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

P0451 (Noise monitor)

TYPICAL ENABLING CONDITIONS

P0451 (Fixed/flat monitor)

TYPICAL ENABLING CONDITIONS

P0452 and P0453:

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

Required Sensors/Components

Canister pump module

Frequency of Operation

Once per driving cycle: P0451 sensor fixed/flat
Continuous: P0451 sensor noise, P0452 and P0453

Duration

0.5 seconds: P0452 and P0453
2 minutes: P0451

MIL Operation

Immediate: P0452 and P0453
2 driving cycles: P0451

Sequence of Operation

None

Monitor runs whenever following DTCs not present

None

Atmospheric pressure (absolute pressure)

70 to 110 kPa-a (525 to 825 mmHg-a)

Battery voltage

10.5 V or more

Intake air temperature

4.4 to 35°C (40 to 95°F)

Canister pressure sensor malfunction (P0452, 0453)

Not detected

Either of following conditions met

A or B

A. Engine condition

Running

B. Time after key off

5 or 7 or 9.5 hours

Monitor runs whenever following DTCs not present

None

Battery voltage

10.5 V or more

Intake air temperature

4.4 to 35°C (40 to 95°F)

Canister pressure sensor malfunction (P0452, 0453)

Not detected

Atmospheric pressure (absolute pressure)

70 to 110 kPa-a (525 to 825 mmHg-a)

Time after key off

5 or 7 or 9.5 hours

Monitor runs whenever following DTCs not present

None

Either of following conditions met

(a) or (b)

(a) Ignition switch

ON

(b) Soak timer

ON

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra