Code P0452, Fuel Tank Drop

[HUMTECH]

Ignition OFF, disconnect the harness connector at the FTP sensor.
 2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal 2 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 volts between the 5-volt reference circuit terminal 3 and ground.
⇒ If less than the specified range, test the 5-volt reference circuit for a short to ground or an 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 scan tool FTP sensor parameter is less than 0.2 volts.
⇒ If greater than the specified range, test the signal circuit terminal 1 for a short to voltage. If the circuit tests normal, replace the ECM.
 5. Install a 3A fused jumper wire between the signal circuit terminal 1 and the 5-volt reference circuit terminal 3. Verify the scan tool FTP sensor parameter is greater than 4.7 volts.
⇒ If less than the specified range, test the signal circuit for 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.