Delco 27SI Troubleshooting – Charging System

Test Step 9. RESTORE THE RESIDUAL MAGNETISM OF THE ROTOR.

1. Connect one end of a jumper wire to the “B+” terminal of the alternator.

2. Connect the other end of the jumper wire to the “R” terminal of the alternator for 2 seconds.

Expected Result:

The voltage output rises on the “B+” terminal. The residual magnetism of the rotor has been restored.

Results:

• YES – The voltage output rises. The residual magnetism of the rotor has been restored. The alternator is now charging.Repair: Exit this procedure and retest the alternator charging system.

  STOP

   

• NO – The voltage output does not rise.Repair: There is an internal problem with the alternator. Replace the alternator or proceed to Systems Operation, “Component Description”. Use the descriptions of the components in order to determine the component that has failed. Proceed to the appropriate component test.

  STOP