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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the B37 engine oil pressure switch.
  2. Ignition ON, verify the scan tool Engine Oil Pressure Switch parameter is OK.
    • If not the specified value, test for the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K20 engine control module.
  3. Install a 3 A fused jumper wire between the signal circuit terminal 1 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 K20 engine control module.
  4. If all circuits test normal, test or replace the B37 engine oil pressure switch.
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