P0453
DTC P0453 - FUEL TANK PRESSURE (FTP) SENSOR CIRCUIT HIGH VOLTAGE
CIRCUIT 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. If the ECM detects that the FTP sensor signal voltage is too high, this DTC sets.
The table illustrates the relationship between FTP sensor signal voltage and the EVAP system pressure/vacuum.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0453 Fuel Tank Pressure (FTP) Sensor Circuit High Voltage
CONDITIONS FOR RUNNING THE DTC
The engine is operating.
CONDITIONS FOR SETTING THE DTC
- The ECM detects the FTP sensor signal voltage is more than 4.6 volts.
- The condition is present for more than 4 seconds.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (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 4 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.
DIAGNOSTIC AIDS
The table illustrates the ECM connector locations:
- Use the J 35616 Connector Test Adapter Kit for any test that requires probing the ECM harness connector or a component harness connector.
- A blocked or clogged EVAP canister may cause this DTC to set.
- For an intermittent condition, refer to Intermittent Conditions. Intermittent Conditions
TEST DESCRIPTION
Step 1 - Step 8:
Step 9 - Step 16:
Step 17 - Step 21:
The number below refers to the step number on the diagnostic table.
2. This step verifies that the condition is present.
8. This step test for high resistance in the low reference circuit of the FTP sensor. The ECM must be completely powered down to obtain an accurate resistance reading. It may take up to 30 minutes for the ECM to power down after the ignition key is removed. Removal of the ECM fuse, or the PCM/ETC fuse, allows the ECM to power down completely.