D150 1/2 Ton Pickup 2WD L6-225 3.7L VIN H 1-bbl (1983)
a. Place ignition switch in "off" position, then disconnect voltage regulator connector.
b. Place ignition switch in "on" position. Do not start engine or distort terminals with voltmeter probe.
c. Ensure battery voltage exists at blue and green leads at voltage regulator wiring harness terminals, then place ignition switch in "off" position.
If results of steps a, b and c are not satisfactory, replace voltage regulator.
3.
Remove voltmeter and tachometer.
Alternator & Regulator Diagnosis
Fig. 5 Charging system diagnosis chart