On Car Test
To check the voltage adjustment value, start engine and load system - a voltage of at least equal to battery voltage should exist between positive and negative terminals at regulator. The control potentiometer may be incorrectly set; adjust to 14 volts with a normal load. Next, note setting of potentiometer, rotate fully clockwise and measure voltage between field and negative terminals; this must be less than 1.5 volts. If so the regulator is operating correctly; reset to the original position.