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Andy4639 · 04-09-2014, 02:46 AM

Putting relays in my truck was one of the easiest mods I've done. Your factory light connection is a 3 wire hook up. Low beam, high beam and ground for both.

-30 = constant [positive (+)] power (usually wired directly to car battery)
-85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car)
-86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.)
-87 = When you hit the headlight switch it sends power to this lead which in turn goes to the high are low beam of the head lights.

You will need 2 relays for the mod one for low beam one for High beam.

04-09-2014, 02:46 AM	#21
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,945	Re: Hid headlights? Putting relays in my truck was one of the easiest mods I've done. Your factory light connection is a 3 wire hook up. Low beam, high beam and ground for both. -30 = constant [positive (+)] power (usually wired directly to car battery) -85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car) -86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.) -87 = When you hit the headlight switch it sends power to this lead which in turn goes to the high are low beam of the head lights. You will need 2 relays for the mod one for low beam one for High beam. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.