MAINTENANCE OF M939 SERIES VEHICLES - OD1661 - LESSON 1/TASK 2
malfunction she will need a mechanic's general toolbox, multimeter,
battery specific gravity tester (optical type), and the simplified
test equipment/internal combustion engine (STE/ICE) test set (if
Once she has determined the necessary tools and
equipment, SGT Elliott gathers these together at the vehicle.
She is now ready to begin the troubleshooting procedures.
before beginning any troubleshooting, she ensures that the vehicle is
configured according to proper safety practices. These are:
o The vehicle is parked.
o The gear selector lever is in neutral (N).
o The parking brake is set.
o The engine is shut down.
o The wheels are chocked.
Once the vehicle has been configured according to the above listed
items, SGT Elliott is ready to begin the troubleshooting procedures.
First, she examines the battery cables, clamps, and posts
for breaks, looseness, corrosion, and damage. Once these items have
been checked, SGT Elliott will check the battery cases for cracks.
Since she found no defects, she will proceed on to step 2.
Step 2. In step 2 SGT Elliott examines the cable that runs from the
battery to the starter, and the cable that runs from the starter to
the frame, for looseness, corrosion, and damage.
Again SGT Elliott
found no defects, so she will proceed to troubleshooting step 3.
In step 3 SGT Elliott is directed to test the specific
The procedures for using the tester can be found
in TM 9-6140-200-14.
Since the specific gravity of the batteries
is within the limits prescribed in the TM, SGT Elliott is directed
to use the STE/ICE tester and perform No-Go test 20.
the purposes of this subcourse it will be assumed that the