TM-9-2350-311-20-1 Maintenance Manual for Volume 1 M109 Hull Download
Page 266 of 1275
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). 3-166