Other parts needed
Wireless 12v switch for turning power to relay and LEDs on and off
Rectifier diodes, Radio Shack part #276-1661
For those who do not understand wiring diagrams or circuitry principles I thought a laymen’s explanation of how all this works would be helpful. If you understand this conceptually, the actual wiring is a piece of cake on the only problem is managing all the wire spaghetti that results.
For wiring always use red for power (+) and black for ground connections.
The relay comes with a diagram that numbers all of the connections, as noted below.
Relay function: Serves as a switching device to channel current to the Rear Lens LEDS in two modes: running light mode and brake light mode
The connection to the high brake light lead serves as the trigger for the relay coil, switching the relay output contacts from one mode to the other when the brake pedal is pressed or released
Relay Coil Trigger: Leads from the high brake light solder to contacts 7 and 8. A diode is wired into the + side before the relay.
Relay Power supply input: Leads from the rear fuse box power source are soldered to contacts 5 and 6. A diode is wired into the plus + side before the relay
Relay output for brake light mode: Leads are soldered to contacts 3 and 4 and connected to the plus and ground leads for the rear lens LEDS
Relay output for running light mode: Leads are soldered to contacts 1 and 2 then run to the plus and ground leads on the dimmer. The plus output lead from the dimmer is then wired through the light sensitive switch and the output from the switch is connected to the rear lens LEDs. The ground lead from the dimmer output is wired directly to the rear lens LED ground connection.
The relay’s default setting (when the coil is not energized) is in running light mode and runs the power supply through the dimmer to the light sensitive switch then to the rear lens LEDs.
The light sensitive switch turns off running light mode in daylight conditions, and via the potentiometer on the switch, its sensitivity can be dialed in to roughly match the sensitivity of the dashboard light sensitivity switch on the Volt.
Pressing on brakes activates the relay coil and switches power to brake light mode, with full brightness of the rear lens LEDS
When brake pedal is released relay coil is de-energized, switching the output back to running light mode and the dimmed brightness set with the dimmer
The LED dimmer provides adjustments for brightness as well as flashing dynamics – so you can experiment and chose what you like. Some interesting bling is possible here.
Next: Tapping into the rear fuse box power source and running the connection to the tailgate