octanejunkie
Elite Member
I installed a set of LED ring halos along with my DDM projectors a while back and finally got around to wiring them up and posting this. RL gets in the way, a lot.
Since I always drive with my markers lights on, I wired the halos into the marker lights, so they turn on with them - but I also wired them so that the halos TURN OFF when the headlights are powered on, using a simple Bosch style automotive relay.
Parts
Halos, obviously
Automotive Relay
Headlight pigtail
Auto wire, 18 GA insulated, red and black
Quick disconnect connectors
And some heat shrink and solder
Wiring
(table schematic below)
I pulled the positive power from the passenger side marker light and wired into a connector since there was more room on that side. I mounted the relay on the inner fender and grounded it to a threaded hole.
Power from the marker goes to a harness that feeds positive power to both halos full time. The ground (negative) for the halos was wired to the relay so it could be switched on/off when the headlamps are powered on, using the normally closed wiring of the relay.
I then made another harness that connects the driver side halo across the radiator core support and zip tied it down after everything was test fitted, and a harness to connect to the factory headlight connector using the pigtail. All harness connections use quick disconnect type connectors and were soldered and heat shrunk.
Relay wiring
All relays have standard numbered terminals, regardless of wire color, so I will reference the terminals by number here - it's easier to do it this way than draw a schematic.
Wired like this, the halos are having their ground toggled off, so when the headlights are turned on they trip the relay to OPEN the connection, disconnecting the ground (negative) to the halos.
I'm sure there are other ways to do this, but it is pretty much how thermostatic-controlled electric cooling fans and many electric fuel pumps are controlled by relays.
Good luck, it was a fun project to do along with my projector retrofit!
Pictures below
Since I always drive with my markers lights on, I wired the halos into the marker lights, so they turn on with them - but I also wired them so that the halos TURN OFF when the headlights are powered on, using a simple Bosch style automotive relay.
Parts
Halos, obviously
Automotive Relay
Headlight pigtail
Auto wire, 18 GA insulated, red and black
Quick disconnect connectors
And some heat shrink and solder
Wiring
(table schematic below)
I pulled the positive power from the passenger side marker light and wired into a connector since there was more room on that side. I mounted the relay on the inner fender and grounded it to a threaded hole.
Power from the marker goes to a harness that feeds positive power to both halos full time. The ground (negative) for the halos was wired to the relay so it could be switched on/off when the headlamps are powered on, using the normally closed wiring of the relay.
I then made another harness that connects the driver side halo across the radiator core support and zip tied it down after everything was test fitted, and a harness to connect to the factory headlight connector using the pigtail. All harness connections use quick disconnect type connectors and were soldered and heat shrunk.
Relay wiring
All relays have standard numbered terminals, regardless of wire color, so I will reference the terminals by number here - it's easier to do it this way than draw a schematic.
30 - wired to good body ground
87 - NOT USED
87A - Ground (negative) to Halo harness (black wire)
86 - (trigger) wired to headlight pigtail connector (the one that provides voltage when the headlights are turned on
85 - (relay ground) connect to chassis ground
87 - NOT USED
87A - Ground (negative) to Halo harness (black wire)
86 - (trigger) wired to headlight pigtail connector (the one that provides voltage when the headlights are turned on
85 - (relay ground) connect to chassis ground
Wired like this, the halos are having their ground toggled off, so when the headlights are turned on they trip the relay to OPEN the connection, disconnecting the ground (negative) to the halos.
I'm sure there are other ways to do this, but it is pretty much how thermostatic-controlled electric cooling fans and many electric fuel pumps are controlled by relays.
Good luck, it was a fun project to do along with my projector retrofit!
Pictures below
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