In my search to find the best way to complete this pet project on my truck, I found this site. I've searched but as I am using a manufactured flush mounted bolt LED lighting unit I still have some questions on how best to set-up the wiring to get the LEDs to do what I want.

Background: I found this Bolt LED when looking through a car forum the other day - http://www.oznium.com/led-bolt/tech I've been trying to find something low-profile that has a simple and secure mechanism to hold it in place. Based on the reviews, these LEDs seem to be pretty decent quality. What I want to do is set-up 4 on each side of my truck along the toe plate of each running board and have them act as both additional parking lights and turn signals. I had previously installed LED light bars and wired them up to my parking lamp and turn signal sources and ground for each side of the car.

I've attached how I think the wiring should be done. I want to make sure I won't be harming the Bolt LEDs. I saw one post talking about the 2 currents "adding together" when both the parking light and turn signal are on. Do I need to be concerned with frying anything? Will the 1N4001 Diode be sufficient for this application? Should I assume a higher voltage than 12V? Is wiring the Bolts in parallel the best method or would wiring them in series make more sense?

Wiring Schematic

Thanks for any help you can provide!


  • \$\begingroup\$ Do you need these LEDs to flash ON and OFF when the turning signal is applied? \$\endgroup\$ Commented Feb 6, 2015 at 17:41
  • \$\begingroup\$ I want them to do the following: -Blink with turn signal -turn on (at a lower brightness) with parking lights -alternate bright/dim when parking lights are o and blinker is activated. Power would be coming directly from tapping into the wiring harness at the bulb sockets so the vehicle would control supplying the voltage from both the parking lamp and the turn signal (2 separate wires). Speaking of, as the parking light stays on (from what I can tell) while the turn signal lights up do I need to worry about both current sources frying the diodes? \$\endgroup\$
    – Steve P
    Commented Feb 6, 2015 at 18:25
  • \$\begingroup\$ That circuit should be fine. I wouldn't be worried about the current frying anything as the internal resistors of the Bolts will automatically limit this to a safe value which is well within the spec. for the 4001 . My only concern would be the flasher unit not having enough current through it to operate the heater/bimetal switch correctly. \$\endgroup\$ Commented Feb 6, 2015 at 19:02
  • \$\begingroup\$ @Jim this is probably parallel to the existing turn signal markers, so I doubt that is an issue. \$\endgroup\$
    – Passerby
    Commented Feb 6, 2015 at 19:29
  • \$\begingroup\$ Oh no, no. The vehicles stock turn signal would still be utilized so the flasher would still have enough current through it to operate the bimetal switch. These LEDs would be in addition to the existing vehicle lighting and would be applied in parallel on the existing circuit. Sorry for the confusion. \$\endgroup\$
    – Steve P
    Commented Feb 6, 2015 at 19:31

1 Answer 1


I'd say you have exactly the right idea, and you don't have to worry about frying anything (unless you connect the LEDs backwards). Your only problem is that the resistor from the parking source is probably too high. I suspect you'd do better with about 100 to 200 ohms, but be prepared to experiment.


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