TM 5-3810-307-24-1-2
TROUBLESHOOTING
Trouble in the charging system will normally be
3. Check battery for state-of-charge. If low,
indicated by one of the following:
recharge according to manufacturer's
specifications and load test to establish
Undercharged or overcharged battery.
serviceability. Further diagnostic tests
require a known good, fully-charged
Short life of light bulbs or other electric
battery for accurate results.
equipment caused by abnormally high system
voltage.
B. SYSTEMS WITHOUT INDICATOR LIGHT
System voltmeter readings outside normal
TEST EQUIPMENT NEEDED:
range.
Diagnose system as follows (refer to Fig. 5):
Voltmeter
A.
ALL CHARGING SYSTEMS
1. If battery is undercharged, or System
voltmeter shows operating voltage is below
TEST EQUIPMENT NEEDED:
acceptable range:
Belt Tension Gage
With engine stopped and all electrical loads
Battery State-of-Charge Indicator
turned off, use voltmeter to check voltage
across battery terminals. Record voltage.
1.
Check electrical system wiring and
battery terminals for poor connections or
Start engine and run at moderate speed.
other obvious conditions that might result
Check voltage across battery terminals with
in shorts, opens, grounds, or high
engine running.
resistance. Correct as necessary.
-
If voltage reading at battery terminals is
2.
Check generator drive belt for proper
different from reading showing at system
tension.
Adjust
to
manufacturer's
voltmeter (if equipped), locate and correct
specifications.
cause of incorrect reading.
Figure 5. Troubleshooting a One-Wire System
D-6 Change-1