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After several hours looking I’ve given up and need help. I’m installing a compressor and want the pressure gauge to illuminate when headlights are on. I thought the wire woukd be one of the 3 harnesses but after unplugging them all the headlights still worked. Please tell me where and which wire I need to splice into so I can finished this up.
The headlamps are wired directly from the BCM to the headlamps without any inline connectors. If you want to tap into the headlamp circuit you either have to do it at the headlamp or at the BCM.
What year is your truck and what type of QE lighting does it have? There are some differences through the years.
Crap, forgot to put that. It’s a 2016 XLT with regular halogens
Here is the circuit.
Your other option is to tie into the Backlighting Circuit coming from the BCM. This is the circuit that provides all the switch backlighting. It branches all over the place so this might be easier.
I think part of the issue may be WHERE are you going to have this pressure gauge mounted. Another possible question is what kind of rear lamps do you have ? ( incandescent or LED).
May want to consider tapping your parking/running light circuit somewhere, less important than headlights and they MUST be on with the headlights.
I think part of the issue may be WHERE are you going to have this pressure gauge mounted. Another possible question is what kind of rear lamps do you have ? ( incandescent or LED).
May want to consider tapping your parking/running light circuit somewhere, less important than headlights and they MUST be on with the headlights.
I’ll be mounting the gauge at base of dash below the headlights dial. I’ve got incandescent lights. I think I do like the idea of tapping the parking lights better actually.
Based on your info to mount near the headlight switch (dial) on the dash, then advise by 52merc to use the Backlighting Circuit is very good. The electrical connector on the back of the headlight switch has backlight power(based on MY2015) on pin #15 (violet with gray strip) and ground on pin #5 (black with blue strip). This would also allow you the dim function for this new light. Would also be a shortest run for the new light wires.
Based on your info to mount near the headlight switch (dial) on the dash, then advise by 52merc to use the Backlighting Circuit is very good. The electrical connector on the back of the headlight switch has backlight power(based on MY2015) on pin #15 (violet with gray strip) and ground on pin #5 (black with blue strip). This would also allow you the dim function for this new light. Would also be a shortest run for the new light wires.
Headlight wire
