Trip Detection Logic

DTC

Monitoring Items

Malfunction Detection Conditions

Trouble Areas

Detection Timings

Detection Logic

P0450

Canister pressure sensor voltage fluctuation abnormal

Sensor output voltage rapidly fluctuates beyond upper and lower malfunction thresholds for 0.5 seconds.

• Canister pump module

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

• ECM

• EVAP monitoring (ignition OFF)

• Ignition ON

1 trip

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 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 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)

• EVAP monitoring (ignition OFF)

1 trip

DTC

Monitoring Items

Malfunction Detection Conditions

Trouble Areas

Detection Timings

Detection Logic

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)

• EVAP monitoring (ignition OFF)

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

The description can be found in the EVAP (Evaporative Emission) System (see page ES-335). MONITOR DESCRIPTION

Canister Pressure Sensor Specification:

(450) (825) (mmHg-a)

HINT:

Standard atmospheric pressure is 101.3 kPa-a (760 mmHg-a)

1. DTC P0450: Canister pressure sensor abnormal fluctuation

If the canister pressure sensor output [pressure] rapidly fluctuates between less than 42.1 kPa-a (315.9 mmHg-a) and more than 123.8 kPa-a (928.4 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 (Evaporative Emission) system monitor. The ECM then illuminates the MIL and sets the DTC (1 trip detection logic).

2. 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 the malfunctions are detected by 2 trip detection logic).

3. 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).

4. DTC P0453: Canister pressure sensor voltage high

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).

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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