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P1451





2UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P1451-P1453: Fuel Tank Pressure Sensor Range/Performance
P1453 - Fuel Tank Pressure Sensor High Input

DTC SUMMARY





DESCRIPTION

Refer to the EVAP System EVAP System.

MONITOR DESCRIPTION

1. P1451: Pressure sensor abnormal voltage fluctuation or being constant

If the pressure sensor output voltage fluctuates rapidly for 10 seconds, the ECM stops the EVAP system monitor. The ECM interprets this as the pressure sensor voltage fluctuating, and stops the EVAP system monitor. The ECM then illuminates the MIL and sets the DTC.

Alternatively, if the sensor output voltage does not change for 10 seconds, the ECM interprets this as the sensor voltage being constant, 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. P1452: Pressure sensor voltage low

If the pressure sensor output is below -17.19 kPa (-128.92 mmHg), the ECM interprets this as an open or short circuit malfunction in the 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. P1453: Pressure sensor voltage high

If the pressure sensor output is more than 23.94 kPa (179.55 mmHg), the ECM interprets this as an open or short circuit malfunction in the 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

P1451 (Noise Monitor):





P1451 (Stuck Monitor):





Key-off monitor sequence 1 to 15

1. Atmospheric pressure measurement





2. First reference pressure measurement





3. Vent valve stuck closed check





4. Vacuum introduction for canister





5. Purge VSV stuck closed check





6. Second reference pressure measurement





7. Canister leak





8. Fuel vapor-containment valve (FVCV stuck closed check)





9. Vacuum introduction for fuel tank





10. FVCV stuck closed check





11. FTP sensor stuck check





12 Third reference pressure measurement





13. Fuel tank leak check





14. FTP sensor stuck check





15. Atmospheric pressure measurement





HINT
"Saturated" indicates that the EVAP pressure change in less than 0.12 kPa (0.9 mmHg) in 30 seconds.

P1452 and P1453:





TYPICAL MALFUNCTION THRESHOLDS

1. P1451: Pressure sensor noise





2. P1451: Pressure sensor stuck





3. P1452: Pressure sensor low voltage





5. P1453: Pressure sensor high voltage





CONFIRMATION DRIVING PATTERN

NOTICE:
- The Evaporative System Check (Automatic Mode) consists of 5 steps performed automatically by the Techstream. It takes a maximum of approximately 18 minutes.
- Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the fuel tank leak check unavailable.
- Do not run the engine during this operation.
- When the temperature of the fuel is 35°C (95°F) or higher, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the fuel temperature below 35°C (95°F).

1. Connect the Techstream to the DLC3.

2. Turn the power switch on (IG) and turn the Techstream on.

3. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / Intake Air Temp B1S1 and Intake Air Temp B2S1.

4. Check that the intake air temperature is between 4.4 and 35°C (40 and 95°F).

5. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.

6. Turn the power switch off and wait for 30 seconds.

7. Turn the power switch on (IG) and turn the Techstream on.

8. Enter the following menus: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.

9. After the "Evaporative System Check" is completed, check for All Readiness by entering the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

10. Input the DTC: P1451, P1452 or P1453.

11. Check the DTC judgment result.





HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.

12. If the judgment result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

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 tank cap.
- Do not disassemble the canister pump module.
- The Techstream is required to conduct the following diagnostic troubleshooting procedure.

PROCEDURE

1. CONFIRM DTC AND FUEL TANK PRESSURE

(a) Connect the Techstream to the DLC3.

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

(c) Turn the Techstream ON.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(e) Read DTCs.

(f) Enter the following menus: Powertrain / Engine and ECT / Data List / Vapor Pressure Tank.

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

Result





B -- CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - BODY GROUND)

C -- REPLACE FUEL TANK PRESSURE SENSOR
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - ECM)





(a) Turn the power switch off.

(b) Disconnect the A13 ECM connector.

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

Result





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

3. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - ECM)





(a) Remove the fuel tank assembly.

(b) Disconnect the m1 fuel tank pressure sensor connector.

(c) Disconnect the A13 ECM connector.

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

Result





B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - BODY GROUND)





(a) Remove the fuel tank assembly.

(b) Disconnect the m1 fuel tank pressure sensor connector.

(c) Turn the power switch on (IG).

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

Standard:





Result





B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.

5. REPLACE FUEL TANK PRESSURE SENSOR

(a) Replace the fuel tank pressure sensor Removal.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

6. REPAIR OR REPLACE HARNESS OR CONNECTOR

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

NEXT -- CHECK WHETHER DTC OUTPUT RECURS

7. REPLACE ECM

(a) Replace the ECM Removal.

NEXT -- Continue to next step.

8. CHECK WHETHER DTC OUTPUT RECURS

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG) and turn the Techstream ON.

(c) Perform the Evaporative System Check using the Techstream, referring to the Confirmation Driving Pattern.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.

HINT
If no pending DTC is displayed on the Techstream, the repair has been successfully completed.

NEXT -- REPAIR COMPLETED