LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2002 >> Forester Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 46 (Generators & Regulators) >> Description & Operation

Description & Operation

WARNING: This page is about a different car, the 2004 Subaru Forester and 2003 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

The generator has a built-in regulator with diagnostic functions and voltage regulating functions, such as the following:

  1. Voltage regulation: The On-Off operation of transistor TR1 connects and disconnects the field current circuit which provides a constant output voltage level. See Fig 1 .
  2. Diagnosis warning is when any of the following problems occur the charge lamp illuminates:
    1. No voltage generation: Brush wear exceeds specified wear limits, field coil circuit is broken, etc.
    2. Excessive output: Output voltage is greater than 16 volts (approximately.)
    3. Terminal B disconnection: Harness is disconnected from alternator terminal B.
    4. Terminal S disconnection: Harness is disconnected from alternator terminal S. In this case, voltage is slightly greater than specified regulated voltage; however, voltage regulation is still controlled and the battery is prevented from overcharging.
Fig 1: Generator Circuit Diagram
G00211627Courtesy of SUBARU OF AMERICA, INC.