Charge Lamp Stays ON With Eng Running

1. Measure voltage at voltage regulator test point "A." If voltage is equal to battery voltage, proceed to step 2. If voltage is not equal to battery voltage, service open circuit between alternator test point "A" and power distribution box. Ensure fuse for circuit is in good condition.
2. Remove three-pin voltage regulator connector and turn ignition switch to RUN position. If indicator lamp is not ON, proceed to step 3. If indicator lamp is still ON, service short to ground in circuit between alternator "I" and indicator lamp.
3. Connect voltage regulator connector and remove one-pin "S" connector. Use jumper wire to connect wiring harness "S" terminal to positive battery post. If indicator lamp is OFF, proceed to step 4. If indicator lamp is ON, proceed as follows:
a. Remove three-pin voltage regulator connector.
b. Measure wiring resistance between one-pin "S" connector and center "S" pin of voltage regulator connector.
c. If resistance is greater than one ohm, service open or excess resistance in "S" circuit.
d. If resistance is less than one ohm, check of loose or bent voltage regulator or connector pins. If no pin problem is found, replace voltage regulator.
4. Start engine and measure voltage at "S" terminal on back of alternator. If voltage is at least 1/2 battery voltage, proceed to step 5. If voltage is not at least 1/2 battery voltage, refer to System Does Not Charge. System Does Not Charge
5. Measure voltage at "B+" terminal on back of alternator with engine running at 2000 rpm and accessories turned OFF. If voltage is more than 15.5 volts, refer to System Overcharges. If voltage is less than 15.5 volts, replace voltage regulator. System Overcharges (Battery Boils Over)