P0452
DTC P0452 or P0453
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Strategy Based Diagnosis Strategy Based Diagnosis
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions
DTC Descriptors
DTC P0452
- Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage
DTC P0453
- Fuel Tank Pressure (FTP) Sensor Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The evaporative emission (EVAP) system is used to store fuel vapors in order to reduce the amount of fuel vapors into the atmosphere. The fuel tank pressure (FTP) sensor is only used for EVAP system diagnostics. The FTP sensor is a transducer that varies resistance according to changes in the fuel tank pressure. The engine control module (ECM) monitors the FTP sensor signal in order to detect vacuum decay and excess vacuum during the EVAP system diagnostic test. The ECM supplies a 5-volt reference and a low reference circuit to the FTP sensor.
Conditions for Running the DTC
* The ignition is ON or the engine is operating.
* The DTCs run continuously once the above condition is met.
Conditions for Setting the DTC
P0452
The ECM detects the FTP sensor voltage is less than 0.2 volt.
P0453
The ECM detects the FTP sensor voltage is more than 4.8 volts.
Action Taken When the DTC Sets
DTC P0452 and P0453 are Type B DTCs.
Conditions for Clearing the DTC
DTC P0452 and P0453 are Type B DTCs.
Diagnostic Aids
* If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.
* The scan tool 5 volt reference parameter should display between 4.8-5.2 volts.
Reference Information
Schematic Reference
Engine Controls Schematics (w/Throttle Actuator Controls) Electrical DiagramsEngine Controls Schematics (w/o Throttle Actuator Control) Electrical Diagrams
Connector End View Reference
* Engine Control Module Connector End Views (w/ Throttle Actuator Control) Engine Control Module Connector End Views (w/ Throttle Actuator Control)Engine Control Module Connector End Views (w/o Throttle Actuator Control) Engine Control Module Connector End Views (w/o Throttle Actuator Control)
* Engine Controls Connector End Views (w/ Throttle Actuator Control) Engine Controls Connector End Views (w/ Throttle Actuator Control)Engine Controls Connector End Views (w/o Throttle Actuator Control) Engine Controls Connector End Views (w/o Throttle Actuator Control)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
* Scan Tool Data List (w/ Throttle Actuator Control) Scan Tool Data List (w/ Throttle Actuator Control)Scan Tool Data List (w/o Throttle Actuator Control) Scan Tool Data List (w/o Throttle Actuator Control)
* Scan Tool Data Definitions (w/ Throttle Actuator Control) Scan Tool Data Definitions (w/ Throttle Actuator Control)Scan Tool Data Definitions (w/o Throttle Actuator Control) Scan Tool Data Definitions (w/o Throttle Actuator Control)
* Scan Tool Output Controls (w/ Throttle Actuator Control) Scan Tool Output Controls (w/ Throttle Actuator Control)Scan Tool Output Controls (w/o Throttle Actuator Control) Scan Tool Output Controls (w/o Throttle Actuator Control)
Circuit/System Verification
1. Ignition ON, observe the DTC information with a scan tool. Verify DTC P0651 is not set.
• If DTC P0651 is set, refer to DTC P0641 or P0651 P0641.
2. Observe the scan tool FTP Sensor voltage parameter. The FTP sensor voltage should be between 0.2-4.0 volts.
3. If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector of the FTP sensor.
2. Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit and ground.
• If greater than 5 ohms, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace the ECM.
Important: The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.
3. Ignition ON, load test for 4.8-5.2 volts between the 5-volt reference circuit and ground.
• If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit/connections test normal, replace the ECM.
• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.
4. Ignition ON, verify that the scan tool FTP Sensor voltage parameter is less than 4.8 volts
• If greater than the specified value, test the signal circuit for a short to voltage. If the circuit/connections test normal, replace the ECM.
5. Install a 3-amp fused jumper wire between the signal circuit and the 5-volt reference circuit. Verify that the scan tool FTP Sensor voltage parameter is greater than 4.8 volts.
• If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test normal, replace the ECM.
6. If all circuits/connections test normal, replace the FTP sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Fuel Tank Pressure Sensor Replacement Service and Repair
* Control Module References Control Module References for engine control module replacement, setup, and programming