TM 5-3805-262-20
E-4. TROUBLESHOOTING (CONT)
c. Check troubleshooting index for most likely cause, then identify the circuit
that is malfunctioning.
d. Study the electrical schematic to learn which components, harnesses, or wires
could contribute to or cause the malfunction.
NOTE
Remember, when tracing circuits on the electrical schematic, that you
should always start at the positive (+) side of the battery.
Current
will flow outward from that point through the circuits and return to the
negative (-) side of the battery by way of ground wires and the vehicle
frame.
e. Make necessary tests and checks to isolate circuit or component as outlined in
the troubleshooting section of this technical manual.
f. Make repairs, if youre sure.
If not, continue to isolate the malfunction, or
ask for help from your foreman or supervisor.
g. After repairs, make sure everything has been re-connected and tightened.
h. Make operational checks to verify that the system/circuit is functioning
properly again.
E-5. TROUBLESHOOTING LOGIC TREE
Figure E-1 is a Troubleshooting logic tree.
It is designed to help you develop a
quick logical way of approaching an electrical troubleshooting problem.
E-6. ELECTRICAL SYMBOLS
Figure E-2 shows you the basic electrical symbols used with most schematics. They
will help you read and understand the electrical circuits.
E-2