TM 9-2350-311 -20-1
3-3
TROUBLESHOOTING CHART — CONTINUED
m. ALTERNATOR CIRCUIT (M109A2/M109A3) —
ALTERNATOR FAILS TO CHARGE BATTERIES; GAGE
CONTINUED
INDICATION: NOT CHARGING, UNSTEADY OR
INACCURATE READING — CONTINUED
CONTINUED FROM STEP M
1
CAUTION
Rheostat turns easily. Do not force beyond the stops or
damage to regulator may occur.
M
7. With engine running at 1000 rpm, use a
screwdriver to adjust rheostat to obtain a
voltage reading of 27.5 to 28.5 Vdc. Turn
screwdriver counterclockwise to reduce
voltage. Slowly turn screwdriver to bring
regulated voltage up to 27.5 to 28.5 Vdc.
8. Replace pipe plug in end of voltage
regulator.
9. Turn off vehicle headlights.
10. Repeat step 4. If this check is satisfactory,
shut off engine and remove multimeters.
11. If voltage regulator cannot be adjusted,
replace regulator (para 8-3).
12. If electrical (battery) problems continue after
regulator has been properly checked
and/or adjusted, check service,
maintenance, and usage of battery
(TM 9-6140-200-1 4).
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