any electronic component can be shorted and yes it's def possible to have a bad one out of the box. for the loc you'll need to connect to the speaker outputs from the headunit if you don't already. it's also possible that the new amp could be bad. you can take a multimeter and test the ac output from the rca's coming out of the loc to see if you're getting signal from there or not.
2013 F150 4x4 SCrew XLT 5.0L
Midwest Crew #22
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