TM 5-3805-262-34
2-6. ALTERNATOR TROUBLESHOOTING
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. ALTERNATOR NOT CHARGING BATTERIES.
Step 1.
Disassemble alternator (page 3-202).
Inspect brush holder for worn or damaged brushes.
a. If brushes are worn or damaged, replace brush holder and
reassemble alternator (page 3-214).
b. If brushes are okay, go to step 2 below.
Step 2.
Test stator (page 3-213).
a. Replace stator if defective and reassemble alternator (page
3-214) .
b. If stator tests okay, go to step 3 below.
Step 3.
Test diode trio (page 3-211).
a. Replace diode trio if defective and reassemble alternator (page
3-214) .
b. If diode trio tests okay, go to step 4 below.
Step 4.
Test rotor (page 3-213).
a. Replace rotor if defective and reassemble alternator (page
3-214) .
b. If rotor tests okay, replace rectifier bridge and reassemble al-
ternator (page 3-214).
2. ALTERNATOR NOISY.
Step 1.
Manually turn rotor shaft and check that rotor rotates
a. If rotor shaft does not rotate freely, disassemble
freely.
alternator
(page 3-202). Inspect and replace
sary. Reassemble alternator (page
b. If rotor shaft rotates freely, go
Step 2.
Disassemble alternator (page 3-202).
Test rectifier bridge (page 3-212).
alternator bearings as neces-
3-214) .
to step 2 below.
a. Replace rectifier bridge if defective and reassemble alternator
(page 3-214).
b. If rectifier bridge tests okay, replace stator and reassemble
alternator (page 3-214).
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