LUCAS Alternator With Integral Regulator: Overhaul: Testing: Diodes

Connect a 12-volt battery and a 1.5-watt test lamp in turn to each of the nine diode pins and its corresponding heat sink on the rectifier pack, then reverse the connections. Lamp should light (with current flow) in one direction only. If lamp lights in both directions or fails in either, rectifier pack must be renewed.