M2/M3 BFV: TROUBLESHOOTING - OD1610 - LESSON 1/TASK 1
(c) Isolate.
This is the final sub-step in the troubleshooting
procedure.
After the malfunction has been localized to a general area of
the faulty circuit or section, the next step is to isolate the faulty
component either by a visual inspection or by performing diagnostic test
measurements such as voltage resistance, capacitance, etc. In this way, you
pinpoint the actual cause of the malfunction.
To illustrate the material that has been covered thus far in the task, let's
set up a little scenario. Let's assume that your wife has been complaining
that the car is not running right. From the material covered thus far, we
must first verify that the malfunction exists.
The first step in
troubleshooting, in the Army, normally, is to read the DA Form 2404;
however, since it is not likely that your wife will write this up on a DA
Form 2404, that step will be eliminated.
So, the first thing that you do is to ask her what actually is wrong. She
says that the car has been spitting and sputtering and when she mashes down
on the accelerator, the car hesitates before picking up speed. She informs
you that this has been getting worse as the weeks wear on. You decide to
take the car for a test drive and, sure enough, she was right; it's
spitting, sputtering and hesitating like crazy.
You decide that since
Friday is payday, you will work on the car Saturday.
What you have just
accomplished is the first step in troubleshooting, verifying that the
malfunction exists.
Saturday arrives and it's a gorgeous day, sunny and warm. So out into the
driveway you march armed with your little toolbox. From your knowledge of
automotive principles and maintenance, you have determined that the problem
is in the fuel system. You have just sectionalized the problem to a portion
of the car, namely the fuel system. Since the gas tank is full, and since
you and your wife both buy your gas at the Post Exchange gas station, you
rule out the possibility that the car is either out of gas or that there is
water in the gas. That means that the problem lies somewhere between the
gas tank and the carburetor.
This is known as localizing, narrowing the
malfunction down to a more precise area of the problem section.
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