LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2008 >> Optra LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 2.0L (Diesel) >> Diagnostic Information and Procedures >> DTC P0069 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

  1. Ignition ON, compare the scan tool BARO pressure sensor parameter to the reading in the table.
  2. Ignition OFF, and the MAIN fuse removed, disconnect the harness connector at the turbocharger boost pressure sensor.
  3. Test for less than 5 ohms between the low reference circuit terminal 4 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.
  4. Install the MAIN fuse. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 2 and ground.
    • If less than the specified range, test the 5-volt reference circuit for a short to ground or 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.
  5. Verify the scan tool MAP sensor parameter is less than 24 kPa.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  6. Install a 3A fused jumper wire between the signal circuit terminal 1 and the 5-volt reference circuit terminal 2. Verify the MAP sensor parameter is between 40-45 kPa.
    • If less than the specified range, test the signal circuit for an open or a short to ground. If the circuit tests normal, replace the ECM.
    • If greater than the specified range, test the signal circuit for a high resistance. If the circuit tests normal, replace the ECM.
  7. If all circuits test normal, test or replace the turbocharger boost pressure sensor.