LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2008 >> Allure CXL >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 10 (Engine Control System & Fuel System - 5.3L - DTC P0420 To DTC P3449) >> DTC P0451, P0452, P0453, or P0454 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  1. Ignition OFF, disconnect the harness connector at the FTP sensor.
  2. Ignition OFF, ensure that the ECM completely powers down and test for less than 5 ohms between the low reference circuit terminal 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 control module.
  3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 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 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.
  4. Verify the scan tool FTP sensor parameter is less than 0.2 volt.
    • If greater than the specified range, test the signal circuit terminal for a short to voltage. If the circuit tests normal, replace the control module.
  5. Install a 3A fused jumper wire at the signal circuit terminal and the 5-volt reference circuit terminal. Verify the scan tool FTP sensor voltage parameter is greater than 4.7 volts.
    • 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.
  6. If all circuits test normal, replace the FTP sensor.
scientia non olet · About LEMON Manuals