How to test Tip122 and IRL 540 transistors in and out of circuit.

For the most part, when these components fail, they will short.  Although it is best to remove the component
in question to do these tests it can be done in circuit and without removing them.  Use a multi-meter set it to
diode test/check. If the component tests shorted in circuit remove from board to confirm if truly shorted. If the component tests shorted in circuit remove from board to confirm if truly shorted.

How to test Tip122