Alternators W/Integral Regulators

Fig. 10 Charging Circuit Test Points. Alternator w/integral Regulator:

1. If voltmeter reading indicates 2 volts or over battery voltage (over voltage), proceed as follows:
a. Stop engine and place ignition switch in the ``On'' position, then connect voltmeter negative lead to the alternator rear housing.
b. Connect voltmeter positive lead first to the alternator output connection at the starter solenoid, then to the regulator ``A'' screw head, Fig. 10.
c. If the voltage difference between the two locations is greater than .5 volts, repair the ``A'' wiring circuit to eliminate the high resistance condition indicated by the excessive voltage drop.
d. If over voltage condition still exists, check for loose regulator to alternator grounding screws. Torque regulator grounding screws to 15-26 inch lbs.
e. If over voltage condition still exists, connect voltmeter negative lead to the alternator rear housing.
f. Place ignition switch in the ``Off'' position, then connect voltmeter positive lead first to the regulator ``A'' screw head and then to the regulator ``F'' screw head, Fig. 10.
g. Different voltage readings at the two screw heads in step 1f indicates a defective regulator, grounded brush lead or grounded rotor coil. Repair or replace as required.
h. If battery voltage is obtained at both screw heads in step 1f, replace regulator.
2. If voltmeter does not indicate more than .5 volts over battery voltage, proceed as follows:
a. Disconnect wiring plug from regulator, then connect an ohmmeter between regulator ``A'' and ``F'' terminal screws, Fig. 10. Meter should indicate more than 2.4 ohms.
b. If meter indicates less than 2.4 ohms in step 2a, check integral alternator/regulator unit for a defective regulator, then check the alternator for a shorted rotor or field circuit. Perform Charging System Test procedure after servicing alternator. Do not replace the regulator until a shorted rotor coil or field circuit has been serviced.
c. If meter indicates greater than 2.4 ohms in step 2a, reconnect regulator wiring plug. Connect voltmeter ground lead to the alternator rear housing and voltmeter positive lead to the regulator ``A'' terminal screw.
d. Meter should read battery voltage. If battery voltage is not present, repair ``A'' wiring circuit, then perform Charging Circuit Test procedure. If battery voltage is present, connect the voltmeter ground lead to the alternator rear housing.
e. Place ignition switch in the ``Off'' position, then connect voltmeter positive lead to the regulator ``F'' terminal screw. Meter should indicate battery voltage.
f. If voltage is not present, check integral alternator/regulator unit for an open field circuit. Repair as required, then perform Charging Circuit Test procedure. If voltmeter indicates battery voltage, connect voltmeter negative ground lead to alternator rear housing.
g. Turn ignition switch to the ``On'' position and connect voltmeter positive probe lead to the regulator ``F'' terminal screw. Voltmeter should indicate 1.5 volts or less.
h. If more than 1.5 volts is present, proceed to ``I Circuit Test.'' If ``I Circuit'' is satisfactory, replace the regulator and perform Charging Circuit Test procedure. If 1.5 volts or less is present, disconnect alternator wiring plug and connect suitable jumper wires between the alternator B(+) terminal and mating wiring connector terminals.
i. Perform Charging System Test procedure, but connect voltmeter positive terminal to one of the B(+) jumper wire terminals.
j. If voltage rises more than .5 volts above battery voltage, check alternator and starter relay wiring, then repeat Charging System Test procedure, measuring voltage at battery cable clamps.
k. If voltage does not rise more than .5 volts above battery voltage, connect jumper wire from alternator rear housing to the regulator ``F'' terminal.
l. Repeat Charging System Tests procedure with voltmeter positive lead connected to one of the jumper wire terminals.
m. If voltage rises more than .5 volts, replace regulator. If voltage does not rise more than .5 volts, service the alternator.