86M 2071

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 eight diodes (four pairs), each diode must be tested for continuity in both directions with an ohmmeter that has diode checking capability; a total of 16 checks.

86M 2071

A    E (earth)

1. Check for continuity in each direction between the B and P, and between the E (earth) and P terminals of each diode pair. All diodes sho uld have continuity in only one direction.
2. If any of the eight diodes fails, replace the rectifier assembly. (Diodes are not available separately).

Alternator Brush Inspection

86M 2072

A    Brush holder
B    Alternator brushes
C    Vernier caliper

1. Remove the end cover, then take out the brush holder by removing its two screws.
2. Measure the length of the brushes with a vernier caliper as shown.

Alternator Brush Length

Standard: 10.5 mm
Service Limit: 1.5 mm

If the brushes are less than the service limit, replace the alternator brush assembly.