Originally Posted by Fx4wannabe01
You got a under the hood or in cab wire to splice into the reverse lights?? Maybe that cube of wires under the driver seat, under the cab??
I'd love to have my aux reverse lights come one when i go in reverse, and have the ability to switch them on whenever I want.
You'll need the following parts:
1. One SPST or SPDT relay
2. One SPST switch of your choice
3. One 5 amp inline fuse
4. One 1N4001 Diode (Radio Shack # 276-1101)
5. Wire 18 ga.
On Manual Trans you can tap the reverse switch at the tranny. Theres two wires, one VT/OG and one BK/PK. You'll want to tap the BK/PK wire at or near the switch. Run that wire over to the drivers side and up through the rubber plug into the cab and along the door sill and up to the dash (your choice as to where you want to put the relay & switch). Now you want to solder onto the end of that wire the diode ensuring the silver band on the diode is facing torwards the relay. Solder on another section of wire to the other end of the diode and connect it to terminal 86 of the relay. Next run a properly fused power feed for your Aux lights to terminal 87. Connect the wiring coming from your Aux lights to terminal 30. Now connect terminal 85 to ground.
Next install your override switch on dash and run a power feed either from IGN or BAT (your choice if you want the lights to be able to switched on any time or only with the key on). Ensure you put a 5 amp inline fuse close to where you tap the power. Run the other end to your switch. Run the other wire coming off the switch to terminal 86 on the relay.
Once you have this all hook up you should be able to turn on the Aux lights with the dash switch or whenever you put the vehicle in reverse with the key on they should also come on.
If you'd like to keep them from coming on with the reverse lights you could install a second switch on the dash and run the wire coming from terminal 85 of the relay to this switch and the other wire from the switch to ground.
If you only want one switch on the dash to do both functions you can sub a single three position DPDT rocker switch and use one side (position) for the Aux light control and the other side (position) for the ground cut out, i.e., rocker switch up = lights on, rocker switch in center = operates with reverse switch on tranny, rocker switch down Aux lights off.