air dam warning system

I just completed a warning system for avoiding contact with the airdam and a curb. It uses a microswitch, 1/16" stainless steel wire, and red led with fiberoptic cable to produce a warning light before you hit your airdam and possibly damage it. I am routing the fiberoptic cable to the cowl at the foam seal on the end. It will be located under the lip of the hood. I also put a heat shield over the fiberoptic cable to protect it from the heat in the engine compartment, and to keep it from glowing in the engine compartment. The LED remains with the module on the backside of the metal bumper. You can use the "hot in start, run" wire to the vapor recovery solenoid, and ground it to the fender at the battery ground. The loop at the end of the wire does two things; keeps someone from poking themselves when working under the car, and allows the wire to go back over an accidentally traversed object. The bottom of the loop is 6.75" from the top of the anti-rotation tab, which goes under the bottom of the metal bumper. I made the bracket from a sheet of 1/16" 5052 aluminum, and used a model airplane 1/16" wheel collar and a guide slot to make guaranteed contact with the switch arm. The LED requires a current limiting resistor on the + side, and the - side goes to the switch and then ground. The wires and fiberoptic cable will use a zip-tie, or a piece of heat shrink tubing to attach to the tab. To attach the fiberoptic cable to the LED, I used a 3 mm LED, and a 3 mm cable. I put a 1" piece of 1/8" ID brass tubing over the LED, crimping it a little to make it snug, and the same with the cable. I used a peice of heat shrink tubing to encompass the assembly and keep the parts from separating.

When the wire touches a curb, it bends (about an inch) until the microswitch activates, turning on the LED.

neat project Fred.

If someone wants to make one, I have a box full of microswitches.