so I figured out the headlights today, it is now a 24hr vehicle instead of daylight hours. right now it is low beam only though...
and I know the reason why. that doesnt sound astounding when I say it but believe me there was a lot of rejoicing when I actually figured out what was going on. I looked up the wiring diagram but it didnt tell me anything I didnt already know, just verified that everything was wired correctly.
there are three states of headlights, drl, low beam, high beam. sounds simple, but there is a BCM in there. what was happening was, the low beams would come on with the drls, and the high beams would come on with the low beams. I looked all over for shorts, none, found a couple grounds that were off in the rear but wasnt optimistic that would fix anything. I started by metering out the individual wires and found out that...
ground is controlled by the BCM.
this was a revelation. In most everything DC and even some AC, ground is ground. you wire the 12v through a switch or relay or transistor or whatever and ground is just there. "plane" old ground. in an s10 with a bcm though, depending on the state, ground or power both can be switched. the DRL circuit for example, battery voltage to high beam + and only -11vdc to high beam -. I didnt figure this mattered much to me because the light I am using have an HID for low beam and H3 for high beam, with separate wires for each. I have the HID relay hooked up to the low beam wires, no problem there, and a big separate ground for the ballasts, and the high beam two wires wired to.. the... H....... ah crap. H3 bulbs dont HAVE a separate ground. I turned on the headlights and disconnected the grounds and sure enough, they stayed on. a couple screws confirm my suspicion.
so that means the "plastic" housing on these headlights isnt plastic at all.
nope, aluminum. there was the short I was chasing, I was pushing -14.4vdc alternator voltage back through the -11vdc BCM circuit. nice.
I will pick up some plastic screws tomorrow to isolate the h3 "ground" from the body ground. But for now I can drive the **** out of it any time day or night.
here are the pics of the glovebox I shooped de dooped yesterday.
