How to Replace the Voltage Regulator in a Subaru Outback

The voltage regulator is contained in the Subaru Outback's alternator. This is one of the few vehicles where the regulator can be replaced by itself, but replacing the alternator as a whole may still be a better option. You must have a full working knowledge of the alternator and be an expert at using a soldering iron to replace the regulator without causing more damage.

Things You'll Need

  • Replacement voltage regulator
  • Wrench
  • Flathead screwdriver
  • Vise
  • Soldering iron
  • Remove the alternator from the Outback's engine and the four through bolts. Disassemble the alternator by prying the stator core and front bracket apart with a flathead screwdriver.

  • Hold the alternator rotor within a vise, placing aluminum or wood pieces on the vise surfaces to prevent damage to the rotor. Remove the pulley nut from the rotor.

  • Unsolder the connection between the rectifier and stator coil to remove the stator coil. Remove the screws securing the voltage regulator to the rear cover. Unsolder the connection between the voltage regulator and the rectifier to remove the regulator.

  • Solder the replacement regulator to the rectifier and screw the regulator back on the rear cover. Solder the rectifier and stator coil back together.

  • Reconnect the pulley nut to the rotor, then the stator core and front bracket.

  • Install the alternator back on the engine. Turn the pulley by hand to make sure the rotor turns smoothly.