Alternators - DELCO-REMY With Separate Regulator: Overhaul: Testing: Diodes

With diodes disconnected from stator leads, check by using an ohmmeter (test A) or 12 volt test lamp (test B) as follows:

1. Use an ohmmeter with a 1 1/4 volt cell and use lowest range scale. Connect one ohmmeter probe to end frame and other probe to diode and note ohmmeter readings. Reverse ohmmeter leads and note reading. If both readings are high or low, diode is defective. A good diode will give one low and one high reading.
2. Using a 12 volt test lamp, connect one test lamp probe to diode and other probe to heat sink or end frame, then reverse test lamp probes. If lamp lights in both directions or does not light in either direction, diode is defective. A good diode will cause lamp to light in one direction only.