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Home >> Cadillac >> 2017 >> XT5 Base >> Repair and Diagnosis >> Electrical >> Charging Systems >> Battery, Charging System And Starting System >> Diagnostic Information and Procedures >> Starter Solenoid Does Not Click >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition ON.
  2. Verify the scan tool ECM Ignition 1 Signal parameter is greater than 10 V.
    • If 10 V or less 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the ignition voltage circuits and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, refer to Power Mode Mismatch
    • If greater than 10 V 
  3. Ignition OFF, disconnect the KR27 Starter Relay, ignition ON.
  4. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance,
    3. Disconnect X1 harness connector at the M64 Starter Motor.
    4. Test for infinite resistance between the control circuit terminal 87 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the M64 Starter Motor.
    • If the test lamp illuminates 
  5. Ensure the parking brake is applied and the automatic transmission is in PARK or the manual transmission is in neutral. Momentarily install a 30 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87.
  6. Verify the M64 Starter Motor is activated.
    • If the M64 Starter Motor does not activate 
    1. Disconnect the X1 harness connector at the M64 Starter Motor.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If greater the 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the M64 Starter Motor.
    • If the M64 Starter Motor activates 
  7. Ignition OFF, disconnect the KR27C Starter Pinion Solenoid Actuator Relay, ignition ON.
  8. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance,
    3. Disconnect X1 harness connector at the M64 Starter Motor.
    4. Test for infinite resistance between the control circuit terminal 87 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the M64 Starter Motor.
    • If the test lamp illuminates 
  9. Ensure the parking brake is applied and the automatic transmission is in PARK or the manual transmission is in neutral. Momentarily install a 30 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87.
  10. Verify the M64 Starter Motor pinion engages.
    • If the M64 Starter Motor pinion does not engage 
    1. Disconnect the X1 harness connector at the M64 Starter Motor.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If greater the 2 Ω, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the M64 Starter Motor.
    • If the M64 Starter Motor pinion engages 
  11. Test or replace the KR27 Starter Relay.
  12. Ignition CRANK.
  13. Verify the M64 Starter Motor is activated.
    • If the M64 Starter Motor does not activate 

      Test or replace the KR27C Starter Pinion Solenoid Actuator Relay.

    • If the M64 Starter Motor activates 
  14. All OK.
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