I am installing a keyless entry system in a 1996 Chevy Silverado. The wiring harness has two brown wires with a fuse known as +led flash output. The wiring diagram that we have only shows the parking lights+. I believe one brown led flash output wire would go to the parking lights but where does the other brown wire go?

Best guess. To the positive side of an LED (Light Emitting Diode) that flashes when the security system is armed. The keyless entry system probably contains the resistor necessary to operate the LED. The positive side of a typical LED is the one WITHOUT the flat.

Lights+ is probably designed to drive a relay on the high side. Where the other end of the relay is connected to ground. The external, typically automotive style Bosch relay drives the parking lights

I am installing a keyless entry system in a 1996 Chevy Silverado. The wiring harness has two brown wires with a fuse known as +led flash output. The wiring diagram that we have only shows the parking lights+. I believe one brown led flash output wire would go to the parking lights but where does the other brown wire go?

The led light plugs into the module.