P0452

DTC P0452 or P0453

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

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 stores fuel vapors in order to reduce the amount of fuel vapors into the atmosphere. The fuel tank pressure (FTP) sensor is used for EVAP system diagnostics. The FTP sensor is a transducer that varies resistance according to changes in 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 running.
* 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 for greater than 8 seconds.

P0453

The ECM detects the FTP sensor voltage is greater than 4.85 volts for greater than 8 seconds.

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.

Reference Information
Schematic Reference

Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Evaporative Emission Control System Description (Evaporative Emission Control System Description)
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

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify DTC P0641 is not set.

• If DTC P0641 is set, refer to DTC P0641, P0651, P0697, or P06A3 (P0641).

2. Ignition ON, observe the FTP Sensor voltage parameter. The FTP sensor voltage should be between 1.3-1.7 V.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the FTP sensor.
2. Ignition OFF for 1 minute, test for less than 5 ohm between the low reference circuit terminal A and ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Ignition ON, test for 4.8-5.2 V between the 5-volt reference circuit terminal C 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 tests normal, replace the ECM.

• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Verify the FTP Sensor parameter is less than 1 volt.

• If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the ECM.

5. Install a 3 A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the FTP Sensor parameter is greater than 4.8 V.

• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

6. If all circuits test normal, test or 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 (Programming and Relearning) for ECM replacement, setup, and programming