Testing AL-1235 Alternator

To test the AL-1235 alternator: 

  • Stop engine
  • Disconnect connectors from "N" and "F" terminals.
  • Using a volt meter set in the DC voltage position- attach the (+) lead to the A terminal and the (-) lead to a well grounded spot on the engine. Attaching the (-) of you meter directly to the metal frame of the alternator is best. 
  • You should show roughly 12 volts on your meter. This is your base voltage. 
  • Attach a jumper wire to "F" terminal, making sure it does not touch alternator case. An easy method to use a jumper wire with a female blade connector crimped onto one end.
  • Start engine and touch other end of jumper wire to "A" terminal, and observe the voltage displayed in your meter.

lf voltage rises to 13 to 15 volts then the voltage regulator is defective and must be replaced or there is a problem with your wiring.

lf voltage stays the same as the base voltage then alternator defective.