Rectifier Diodes
NOTE:
The diodes are designed to allow current to pass in one direction while blocking it in the opposite direction. Since the alternator rectifier is made up of 8 diodes (4 pairs), each diode must be tested for continuity in both directions with an ohmmeter that has diode checking capability; a total of 16 checks.
- Check for continuity in each direction, between the B and P, and between the E (ground), and P terminals of each diode pair. All diodes should have continuity in only one direction. See Fig 1.
- If any of the 8 diodes fails, replace the rectifier assembly. (Diodes are not available separately)