Close

Alternator

The alternator produces the electrical power needed to recharge the battery and power the vehicle’s electrical system while the engine is running.

Symptoms of Alternator Problems, Wear or Failure

  • Battery warning light may illuminate
  • Engine stalls while driving due to loss of electrical power
  • Dimming of the dashboard and head lights
  • Problems starting the vehicle
  • Repeated need to jump start the vehicle due to dead battery
  • Abnormal noise

Related Repair Advice for Alternators

  • The entire starting and charging system should be inspected before replacing the alternator to eliminate other problems that may be affecting the alternator's performance. For instance, a weak battery and/or battery cables can result in a failed alternator test.
  • The alternator belt may be partially or totally removed while replacing the alternator, so if it shows signs of wear, this is a good time to replace it

Testing the Alternator

Testing the alternator is done to prevent misdiagnosis, and unnecessary component replacement. Repair facilities use professional starting and charging system test equipment that automatically or manually tests every component in the starting and charging system simultaneously, and definitively. Prior to this test being conducted, the entire system must be physically inspected for damage or lack of continuity.