P1451

3MZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P1451: Fuel Tank Pressure Sensor Range/Performance

DTC P1451 - Fuel Tank Pressure Sensor Range/Performance

DTC P1452 - Fuel Tank Pressure Sensor Low Input

DTC P1453 - Fuel Tank Pressure Sensor High Input

DTC SUMMARY





DESCRIPTION

Refer to the EVAP system EVAP System.

MONITOR DESCRIPTION

1 DTC P1451: Pressure sensor abnormal voltage fluctuation or being constant
If the pressure sensor output voltage fluctuates rapidly for 10 seconds, the ECM (included in the HV control ECU) 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 DTC P1452: Pressure sensor voltage low
If the pressure sensor output voltage is below 0.45 V, the ECM (included in the HV control ECU) interprets this as an open or short circuit 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 DTC P1453: Pressure sensor voltage high
If the pressure sensor voltage output is 4.9 V or more, the ECM (included in the HV control ECU) interprets this as an open or short circuit 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):





Example of restart time





P1451 (Stuck Monitor):





Example of restart time






P1452 and P1453:





TYPICAL MALFUNCTION THRESHOLDS

P1451: Pressure sensor noise





P1451: Pressure sensor stuck





P1452: Pressure sensor low voltage





P1453: 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 tank cap.
- Do not disassemble the pump module.
- The Techstream is required to conduct the following diagnostic troubleshooting procedure.

PROCEDURE

1. CONFIRM DTC AND FUEL TANK PRESSURE
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Code.
(e) Read the 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 tester.
Result:






C -- GO TO EVAP INSPECTION PROCEDURE
B -- CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - HV CONTROL ECU)
A -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - HV CONTROL ECU)





(a) Turn the ignition switch off.
(b) Disconnect the H30 HV control ECU connector.
(c) Measure the resistance between the PTNK terminal of the HV control ECU connector and body ground.
Result:





(d) Reconnect the HV control ECU connector.
B -- REPLACE HV CONTROL ECU
A -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - HV CONTROL ECU)





(a) Remove the fuel tank assembly.
(b) Disconnect the V11 fuel tank pressure sensor connector.
(c) Disconnect the H30 HV control ECU connector.
(d) Measure the resistance between the PTNK terminal of the HV control ECU connector and body ground.
Result:





(e) Reconnect the pressure sensor connector.
(f) Reconnect the HV control ECU connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- REPLACE FUEL TANK PRESSURE SENSOR
4. CHECK HARNESS AND CONNECTOR (FUEL TANK PRESSURE SENSOR - HV CONTROL ECU)





(a) Remove the fuel tank assembly.
(b) Disconnect the V11 fuel tank pressure sensor connector.
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage and resistance according to the value(s) in the table below.
Standard:






Result:





(e) Reconnect the canister connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.
5. REPLACE FUEL TANK PRESSURE SENSOR
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)
6. REPAIR OR REPLACE HARNESS OR CONNECTOR
HINT: If the exhaust tail pipe has been removed, go to the next step before reinstalling it.

NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)
7. REPLACE HV CONTROL ECU
NEXT -- CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)
8. CHECK WHETHER DTC OUTPUT RECURS (AFTER REPAIR)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position and turn the tester on.
(c) Wait for at least 60 seconds.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
HINT: If no pending DTC is displayed on the tester, the repair has been successfully completed.

NEXT -- COMPLETED