Originally Posted by AndyF
You might not need a relay but sometimes using a relay makes the whole system safer. For example, you can eliminate the extra current draw in the passenger compartment by wiring the switch to close a ground. Then use the ground to switch the relay. Closing grounds on the switch panel is safer than having a bunch of 12 volt wires running around under the dash.


This is exactly right

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.