nickardo

Its an 02 so I should be alright, I ordered the bcm from Highway 71 out in Minnesota, how should I go about using the headlight to check voltage and amperage and couldnt I use a multimeter or power probe? Im not the best at electrical especially not on light duty automotive and what power and ground should I use for the bcm? I dont know if there's more than one

I have had growing electrical issues with my yukon first it was the brake lights going out (exept the 3rd light), I swapped the brake pedal switch hoping it would fix it, it didn't. Then my headlights went out so I went to my friends house to try and at least diagnose the issues but he pulled the IGN relay while the truck was running but put it back before it died and after that I realized my security light was staying on and I lost control of the interior lights and exterior lights completely, along with that the door chime no longer sounds and my rear wiper no longer works, everything ive read brought me to the bcm grounds or the bcm itself, I checked the grounds and they were fine I tightened them more regardless, and I swapped the bcm with a pre programmed bcm but that still didnt fix the issue, I later realized I didnt swap them correctly by waiting 30 minutes with the battery disconnected, but recently my other friend hooked up a scanner and went through my vehicle to find any bcm codes or anti theft codes and it said I had no communication to the bcm or anti theft system so he tried clearing the codes hoping it was a fluke in the system but it didnt change anything and after I shut the truck off and tried to turn it back on it ran for maybe a second then shut off I dont know whats going on or how to fix the issues I have please help.