Bench Testing: Diodes
Using an ohmmeter, check continuity of all diodes in both directions. Ensure continuity exists in only one direction. See ALTERNATOR DIODES TEST table. See Fig 1. If continuity exists in both directions, diode is shorted. If continuity is not present in either direction, diode is open. If any diode is defective, replace entire diode assembly.
ALTERNATOR DIODES TEST
| Positive (+) Lead | Negative (-) Lead | Continuity |
|---|---|---|
| + Diode Plate | Diode Terminals | Yes |
| Diode Terminals | + Diode Plate | No |
| - Diode Plate | Diode Terminals | No |
| Diode Terminals | - Diode Plate | Yes |