TM 5-3805-262-20
3-13. BATTERY SYSTEM TROUBLESHOOTING
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. BATTERIES NEED WATER FREQUENTLY.
Step 1. Apply parking brake and place transmission control lever in N (neu-
t r a l ) p o s i t i o n .
Tell assistant to start engine and operate at 1800 rpm.
Record voltmeter indication and tell assistant to shut down engine.
a. If voltmeter indicates more than 31 volts, replace alternator
(page 5-10).
b. If voltmeter indicates 24 to 31 volts, go to step 2 below.
Step 2. Test battery open circuit voltage (page 5-142) and battery load ca-
pacity (page 5-143).
a. Replace a defective battery (page 5-148).
b . I f b a t t e r i e s t e s t o k a y , c h e c k w i r i n g c o n n e c t i o n a t a l t e r n a t or
BAT terminal, starter relay, and starter solenoid BAT terminal
for corrosion or loose connection. Clean and tighten connections
as necessary.
If wiring connections are okay, check for high resistance in
battery tables (refer to page 3-69, MALFUNCTION 3, step 5).
2. BATTERIES DISCHARGED OR DO NOT MAINTAIN CHARGE.
S t e p 1 . S e r v i c e b a t t e r i e s ( p a g e 5 - 1 4 0 ).
B a t t e r y e l e c t r o l y t e i s t o x i c a n d c o r r o s i v e . U s e p r o t e c t i v e g o g g l e s a nd
g l o v e s w h e n p e r f o r m i n g t h e f o l l o w i n g . A v o i d c o n t a c t w i t h s k i n , e y e s ,
clothes, and don’t breathe vapors.
a. Clean battery cases and add distilled water to battery cells as
n e c e s s a r y.
b. If batteries are okay, go to step 2 below.
Step 2.
Check cable connections at battery posts.
a. Clean or tighten
b . I f b a t t e r y c a b le
battery cable connections as necessary.
connections are okay, go to step 3 below.
3-99
