P0452

2GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0451-P0453: Evaporative Emission Control System Pressure Sensor Range / Performance


DTC SUMMARY





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

DESCRIPTION

The description can be found in the EVAP (Evaporative Emission) System Component Tests and General Diagnostics.

MONITOR DESCRIPTION





1. DTC P0451: Canister pressure sensor abnormal voltage fluctuation or being constant

If the canister pressure sensor voltage output fluctuates rapidly for 10 seconds, the ECM stops the EVAP system monitor. The ECM interprets this as the canister pressure sensor voltage fluctuating, 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 stuck, and stops the monitor. The ECM then illuminates the MIL and sets the DTC. (Both the malfunctions are detected by 2 trip detection logic.)

2. DTC P0452: Canister pressure sensor voltage low

If the canister pressure sensor voltage output is below 0.45 V, 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 is 4.9 V 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





TYPICAL ENABLING CONDITIONS

All:





P0451 (Noise monitor):





P0451 (Stuck monitor):





P0452 and P0453:





TYPICAL MALFUNCTION THRESHOLDS

(a) P0451: Canister pressure sensor noise





(b) P0451: Canister pressure sensor stuck





(c) P0452: Canister pressure sensor low voltage





(d) P0453: Canister pressure sensor high voltage





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
- When a vehicle is brought into the workshop, leave it as it is. Do not change the vehicle condition. For example, do not tighten the fuel cap.
- Do not disassemble the canister pump module.
- The Techstream is required to conduct the following diagnostic troubleshooting procedure.

PROCEDURE

1. CONFIRM DTC AND EVAP PRESSURE

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch on (IG) (do not start the engine).

(c) Turn the tester on.

(d) Select the following menu items: Powertrain / Engine and ECT / Trouble Code.

(e) Read DTCs.

(f) Select the following menu items: Powertrain / Engine and ECT / Data List / EVAP / Vapor Pressure Pump.

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

Result:





C -- GO TO EVAP SYSTEM

B -- CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)

(a) Turn the ignition switch off.





(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Result:





Text in Illustration





(d) Reconnect the ECM connector.

B -- REPLACE ECM
A -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)

(a) Disconnect the canister pump module connector.





(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Result:





Text in Illustration





(d) Reconnect the canister pump module connector.

(e) Reconnect the ECM connector.

B -- REPAIR OR REPLACE HARNESS OR CONNECTOR (CANISTER PUMP MODULE - ECM)

A -- REPLACE CHARCOAL CANISTER ASSEMBLY

4. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)

(a) Disconnect the canister pump module connector.





(b) Turn the ignition switch on (IG).

(c) Measure the voltage and resistance according to the value(s) in the table below.

Standard voltage:





Standard resistance:





Text in Illustration





Result:





(d) Reconnect the canister pump module connector.

B -- REPAIR OR REPLACE HARNESS OR CONNECTOR (CANISTER PUMP MODULE - ECM)

A -- REPLACE CHARCOAL CANISTER ASSEMBLY

5. REPLACE CHARCOAL CANISTER ASSEMBLY

(a) Replace the canister assembly Components.

NOTICE:
When replacing the canister, check the canister pump module interior and related pipes for water, fuel and other liquids. If liquids are present, check for disconnections and/or cracks in the following: 1) the pipe from the air inlet port to the canister pump module; 2) the canister filter; and 3) the fuel tank vent hose.





NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)

6. REPAIR OR REPLACE HARNESS OR CONNECTOR (CANISTER PUMP MODULE - ECM)

HINT
If the exhaust tailpipe has been removed, go to the next step before reinstalling it.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)

7. REPLACE ECM

(a) Replace the ECM Components.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)

8. CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch on (IG) and turn the tester on.

(c) Wait for at least 60 seconds.

(d) Select the following menu items: Powertrain / Engine and ECT / Trouble Code / Pending.

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

NEXT -- COMPLETED