FixVault

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the B150 fuel tank pressure sensor.
  2. Ignition OFF, test for less than 5 Ω of resistance 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 ECM.
  3. Ignition ON, test for 4.8-5.2V between the 5V reference circuit terminal and ground.
    • If less than the specified range, test the 5V 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 5V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Verify the scan tool B150 fuel tank pressure sensor parameter is less than 0.2V.
    • If greater than the specified range, test the signal circuit terminal for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  5. Install a 3A fused jumper wire between the signal circuit terminal and the 5V reference circuit terminal. Verify the scan tool fuel tank pressure sensor parameter is greater than 4.7V.
    • 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 K20 ECM.
  6. If all circuits test normal, test or replace the B150 fuel tank pressure sensor.