P0454
DTC P0454 EVAP EMISSION SYSTEM-PRESSURE SENSOR INTERMITTENTComponent Location:
COMPONENT LOCATION
GENERAL DESCRIPTION
The evaporative emission control system prevents hydrocarbon vapors from escaping from the fuel tank into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The Fuel Tank Pressure Sensor (FTPS) is an integral part of the evaporative monitoring system. The PCM monitors the FTPS signal to detect vacuum decay and excess vacuum. The FTPS measures the difference between the air pressure inside the fuel tank and outside air pressure to check the purge control solenoid valve operation and for leak detection in the evaporative emission control system by monitoring pressure and vacuum levels in the fuel tank during the purge control solenoid valve operating cycles.
DTC DESCRIPTION
If the difference between maximum and minimum voltage of fuel tank pressure's signal is out of the threshold value, the PCM determines that a fault exists and a DTC is stored.
DTC Detecting Condition:
Schematic Diagram:
MONITOR SCANTOOL DATA
1. Ignition "OFF"
2. Connect Scantool and Engine "ON"
3. Monitor "Fuel Tank Pressure Sensor" parameter on CURRENT DATA.
Specification
4. Is the parameter displayed within specifications?
YES: Fault is intermittent caused by poor contact in FTS's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "W/Harness Inspection" procedure.
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical Systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "Component Inspection " procedure.
COMPONENT INSPECTION
1. Check PCSV
1. Ignition "OFF"
2. Measure resistance between terminals "1" and "2" of the PCSV connector.
Specification: Approx. 20 - 32 Ohms (20 °C (68 °F))
3. Monitor the PCSV signal waveform and verify that the ground voltage is less than approx. 0.3 V and the surge voltage is between 40 V and 60 V.
4. Is the PCSV normal?
YES: Go to "Check FTPS" as below.
NO:
- Substitute with a known - good PCSV and check for proper operation.
- If the problem is corrected, replace PCSV and go to "Verification of Vehicle Repair" procedure.
2. Check FTPS
1. Ignition "OFF"
2. Disconnect Fuel Tank Pressure Sensor connector.
3. Measure resistance between terminal 1 & 3 of FTPS connector (To component Side)
4. Measure resistance between terminal 1 & 2 of FTPS connector (To component Side)
Specification:
Terminal 1 & 3: Approx. 1.1 kOhms
Terminal 1 & 2: Approx. 5.8 kOhms
5. Is the measured resistance within specifications?
YES:
- Substitute with a known - good PCM and check for proper operation.
- If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NO:
- Substitute with a known good FTPS and check for proper operation.
- If the problem is corrected, replace FTPS and go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all readiness tests have been verified as "Complete"
5. Are any DTCs present?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.