Joe,
Your method of testing is just fine, if you have voltage across the two terminals with the brake pedal up and down, then the switch is staying OPEN and is bad.
If you didn't depress the pedal then you only did half of the test and the switch condition is still unknown.
You're ok to use the shorting method, you will not hurt anything as long as you don't go to ground with the jumper wire.
Mike B
