P0453
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 Sensor Circuit Low Voltage
DTC P0453
- Fuel Tank Pressure 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 V reference and a low reference circuit to the FTP sensor.
Conditions for Running the DTC
* The engine speed is greater than 240 RPM.
* The DTCs run continuously once the above conditions are met for 10 s.
Conditions for Setting the DTC
P0452
The ECM detects the FTP sensor signal voltage is less than 0.2 V for 4 s, or a cumulative of 30 s.
P0453
The ECM detects the FTP sensor signal voltage is greater than 4.85 V for 4 s, or a cumulative of 30 s.
Action Taken When the DTC Sets
DTC P0452 and P0453 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTC P0452 and P0453 are Type B DTCs.
Diagnostic Aids
If a shared 5 V reference circuit is shorted to ground or shorted to a voltage, other 5 V reference circuits may be affected.
Reference Information
Schematic Reference
Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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. DTC P0641, P0642 or P0643 should not be set.
• If a DTC is set, refer to DTC P0641-P0643, P0651-P0653, or P0697-P0699 (ECM) (ECM).
2. Observe the FTP Sensor voltage parameter. The FTP sensor voltage should be between 0.2-4.8 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, remove the fuse that supplies B+ to terminal 56-X2 of the K20 ECM.
2. Disconnect the multi-way harness connector X305, located near the fuel tank.
3. Test for less than 5 ohm between the low reference circuit terminal P and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace the K20 ECM.
4. Install the fuse that supplies B+ to terminal 56-X2 of the K20 ECM.
5. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal B and ground.
• If less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit/connections test normal, replace the K20 ECM.
• If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit/connections test normal, replace the K20 ECM.
6. Observe the scan tool B150 FTP sensor parameter. Verify that the FTP Sensor parameter is less than 5 V.
• If greater than the specified value, test the signal circuit terminal E for a short to voltage. If the circuit/connections test normal, replace the K20 ECM.
7. Install a 3 A fused jumper wire between the signal circuit terminal C and the 5 V reference circuit terminal B. Verify that the scan tool FTP Sensor parameter is greater than 5 V.
• 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 K20 ECM.
8. Remove the fuel tank. Refer to Fuel Tank Replacement (Removal and Replacement).
9. Disconnect the B150 FTP sensor connector.
10. Inspect the FTP sensor circuits in the fuel tank harness, between the FTP sensor connector and X305 for the following conditions, and repair as necessary:
* Damaged wiring or terminals
* Open circuits
* Short to ground
* Wire to wire short
11. If all circuits/connections test normal, test or replace the B150 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