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Circuit/System Testing

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

LY7

  1. Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) switch.
  2. Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal B and ground.
    • If greater than the specified value, test the circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
    • If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.
  4. Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool Engine Oil Pressure Switch parameter is Low.
    • If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If all circuits test normal, test or replace the engine oil pressure switch.

LE5 and LAT

  1. Ignition OFF, disconnect the harness connector at the engine oil pressure (EOP) switch.
  2. Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
    • If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the ECM.
  3. Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal A and ground. Verify the scan tool Engine Oil Pressure Switch parameter is Low.
    • If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  4. If all circuits test normal, test or replace the engine oil pressure switch.