I kinda agree with Joe on this...
There's really no way of knowing if the switch is bad, or if there is a problem with the brake system.
The purpose of the switch is to warn the driver of a failure in the brake system. If you lose pressure in the system, either to the front OR rear brakes, the p-valve will flip to the end that works, and at the same time, it will ground the switch, which causes the light to come on. Sometimes, simply bleeding the brakes can cause the p-valve to flip. Either way, the switch has been grounded for some reason or another.
If your brake pedal is firm, is not going down too far, and the cars stops very well, then it is entirely possible the switch just got stuck in the grounded position...but...the only way for that to happen would be for it to have been grounded to begin with.
For instance, at one point, the brake system had a failure, the p-valve flipped, and grounded the switch. Then, the brakes were fixed, but the switch just got stuck. IN this case, changing the switch itself would prolly take care of the issue. The switch is replaceable(in most cases) without having to replace the p-valve. The switch simply screws into the p-valve. You'll lose a bit of brake fluid changing the switch, and the brakes will need to be bled afterward.
You can certainly leave the wire to the switch hanging, and it will not cause any problems with the brake system. However....I would make dang sure the brakes were indeed working properly if I did that.
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Joel Adams
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