P0452
Diagnostic Chart (Part 1 Of 2):
Diagnostic Chart (Part 2 Of 2):
Schematic:
CIRCUIT DESCRIPTION
The fuel tank pressure sensor is used in order to detect a vacuum decay or an excessive vacuum during the EVAP diagnostic routine. The sensor responds to the changes in the fuel tank pressure or vacuum. The signal voltage to the Powertrain Control Module (PCM) varies from a minimum of about 0.2 voltswith pressure in the fuel tank to more than 4.0 volts with a high vacuum in the fuel tank.
CONDITIONS FOR RUNNING THE DTC
The engine is running.
CONDITIONS FOR SETTING THE DTC
The fuel tank pressure sensor voltage is less than than 0.1 volt for more than 25 seconds.
ACTION TAKEN WHEN THE DTC SETS
^ The Malfunction Indicator Lamp (MIL) will illuminate.
^ The PCM will record the operating conditions at the time that the diagnostic fails. The Freeze Frame and Failure Records buffers will store this information.
^ A history DTC stores.
CONDITIONS FOR CLEARING THE MIL/DTC
^ The MIL will turn off after 3 consecutive ignition cycles in which the diagnostic runs without a fault.
^ A history DTC will clear after 40 consecutive warm up cycles without a fault.
^ Use a scan tool to clear the DTCs.
DIAGNOSTIC AIDS
Check for the following conditions:
^ Inspect the PCM harness electrical connectors for the following conditions:
- Any incorrect mating
- Any broken locks
- Any incorrectly formed terminals or damaged terminals
^ Inspect the wiring harness for damage. If the harness appears to be OK, observe the Fuel Tank Pressure display on the scan tool while moving the electrical connectors and the wiring harnesses related to the sensor. A change in the display will indicate the location of the malfunction.
Refer to EVAP System Cleaning before starting repairs.
TEST DESCRIPTION
7. A normal fuel tank pressure sensor voltage output with no pressure or vacuum on the fuel system should be between 1.3 and 1.7 volts.
11. The replacement PCM must be programmed and the Crankshaft Position System Variation Learn procedure must be performed.