Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Buick >> 2011 >> Regal CXL >> Repair and Diagnosis >> Electrical >> Charging Systems >> Battery, Charging System And Starting System >> Diagnostic Information and Procedures >> DTC P0615 >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the KR27 starter relay.
  2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5.0 Ω between the relay ground circuit terminal 86 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Verify a test lamp illuminates between the B+ circuit terminal 30 and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the control circuit terminal 87 for a short to ground.
  4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 87 and ground.
    • If the test lamp illuminates, test the control circuit for a short to voltage.
  5. Parking brake applied and the transmission is in NEUTRAL or PARK. Momentarily install a 30 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87. Verify the M64 starter motor is activated.
    • If the M64 motor does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the M64 starter motor.
  6. Ignition OFF, connect a test lamp between the control circuit terminal 85 and the ground circuit terminal 86.
  7. Transmission in park or neutral, command the starter relay ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    • If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the K20 ECM.
    • If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
  8. If all circuits tests normal, replace the KR27 starter relay.
scientia non olet · About Mike's Workshop Manuals