Toyota Tundra. Manual — part 1388

Fig. 162: Identifying Purge VSV Connector & EFI No. 2 Fuse

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

OK : CHECK ECM POWER SOURCE CIRCUIT (See ECM POWER SOURCE CIRCUIT )

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

D29-2 or EFI No. 2 fuse terminal 2 - Body ground Always

10 kohms or higher

DTC

Monitoring

Item

Malfunction

Detection

Trouble Area

Detection Timing

Detection

Logic

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra

HINT:

Condition

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)



ECM



EVAP
monitoring
(ignition
switch off)

2 trip

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 (2UZ-FE) - Tundra

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

Fig. 163: Voltage Output 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 output [pressure] is below 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

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra

If the canister pressure sensor output [pressure] is 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

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

P0451 (Noise monitor):

TYPICAL ENABLING CONDITIONS - P0451 (NOISE MONITOR)

P0451 (Fixed/flat monitor):

TYPICAL ENABLING CONDITIONS - P0451 (FIXED/FLAT MONITOR)

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 higher

Intake air temperature

4.4 to 40°C (40 to 104°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 higher

Intake air temperature

4.4 to 40°C (40 to 104°F)

Canister pressure sensor malfunction
(P0452, 0453)

Not detected

Atmospheric pressure (absolute pressure)

Less than 70 kPa-a (525 mmHg-a) or 110 kPa-a (825
mmHg-a) or more

Time after key off

5 or 7 or 9.5 hours

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra