TM 9-6140-200-14
3-7 Testing Batteries With a 12 volt Battery Load Tester.
NOTE
Do Not Test 24 volt system with this tester
It will damage the tester. Its a good idea to
Charge the battery after this test.
1. This test evaluates the battery's ability to crank an engine. The tester draws
current from the battery while measuring its voltage level. the voltage level of a
good battery will remain relatively steady under load, but a defective battery
will show a rapid loss in voltage. Battery size (CCA rating) and temperature
will affect test results- follow instructions carefully.
a. Turn off engine, accessories and battery test equipment.
b. Disconnect all vehicle battery cables/clamps.
c. Connect negative (black) clamp to the negative (-) battery post. Connect
the positive (red) clamp to the positive (+) battery post. Make sure a good
electrical connection between post and clamp.
d. With the clamps connected, tester's meter will indicate battery's STATE OF
CHARGE. Recharge battery if state of charge is less than 12.5 volts before
load testing. If charging does not bring voltage to 12.5 battery is defective.
If meter needle is off scale to the left, check for loose or reversed clamps,
other wise battery is defective.
e. Note battery reading's rates in cold cranking amperes (CCA). If rating is not
printed on the battery use the following guideline to estimate battery size.
2HN, 220 CCA; 6TL, 600 CCA; 6TLFP, 625 CCA; and 6TMF, 725 CCA.
f. Depress load switch for ten (10) seconds.
g. Read meter at the end of ten (10) seconds-with switch depressed.
Refer to load test analysis chart following:
3-5