DTC Descriptor
DTC P0452: Fuel Tank Pressure (FTP) Sensor Circuit Low VoltageDiagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
FTP Sensor Low Reference | -- | P0446, P0451 | P0446, P0463, P2068 | -- | P0451 |
FTP Sensor Signal | P0452 | -- | P0452 | P0453 | P0451, P0454 |
FTP Sensor 5-Volt Reference | P0452, P0522, P0532, P0641, P1183, P2228 | P0451 | P0446, P0452 | P0453, P0530, P0641 | -- |
Typical Scan Tool Data
Circuit¹ | Normal Range | Short to Ground | Open | Short to Voltage |
|---|---|---|---|---|
FTP Sensor Low Reference | 0 V | -- | 4.5 V | -- |
FTP Sensor Signal | 0 V | 0 V | 0-1.5 V | 5 V |
FTP Sensor 5-Volt Reference | 0 V | 0-1.5 V | 5 V | |
¹ With EVAP system vented to atmosphere | ||||
Circuit/System Description
The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the evaporative emission (EVAP) system. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies depending on EVAP system pressure or vacuum. The controller also uses this FTP signal to determine atmospheric pressure for use in the engine-off small leak test, DTC P0442. Before using this signal as an atmospheric reference it must first be re-zeroed.
Conditions for Running the DTC
DTC P0452 runs continuously when the ignition is ON.
Conditions for Setting the DTC
The FTP sensor voltage is less than 0.1 volt for more than 5 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the MIL on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Special Tools Required
J 41413-200 Evaporative Emission System Tester (EEST)
Circuit/System Verification
Ignition ON, observe the scan tool fuel tank pressure (FTP) sensor parameter. The reading should be between 1.3-1.7 volts with the fuel cap removed, and change with fuel tank pressure.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the FTP sensor.
- Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal A and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
- Verify the scan tool FTP sensor parameter is less than 0.1 volt.
- Install a 3-amp fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool FTP sensor parameter is greater than 4.7 volts.
- If all circuits test normal, test or replace the FTP sensor.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the control module. |
| ⇒ | If less than the specified range, test the 5-volt reference circuit for a short to round or an open/high resistance. If the circuit tests normal, replace the control module. |
| ⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the control module. |
| ⇒ | If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the control module. |
| ⇒ | 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 control module. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
