I had an issue with a Esclade awhile back, Where the owner replaced the BCM because it would randomly set off all the lights in the lights blinking buzzers buzzing, It would still run but the lights went crazy and the gauges didn't work. He would shut it off disconnect the battery and let it set all night. The next day he would hook up the battery and start it and it would work fine for awhile. He replaced the BCM with a new one and had it programed and it did the same thing. Short story, when I got a hold of it and traced wires for days. Tracing the problem to the new BCM. Cleaned the BCM contacts still nothing. I made sure the plastic connectors were fully inserted then I took a flat screwdriver and proceded to push the wire connectors into the plastic connectors toward the BCM, they moved a little but one moved a lot more and then everything went back to normal and no issues since. Not sure how often things like this happen but it doesen't take much to mess up a cam-bus system.

 

Finally back to this after being occupied with work. I noticed the passenger side DRL/Turn Signal LED would flicker upon start up for about 20 seconds then remain on like normal and as I said the turn signals/DRL's worked fine when lights were off. Well, I disconnected the passenger side DRL/Turn signal and plugged the old factory bulb back in and when the passenger side turn signal was on, the HVAC did not flash. It also worked while the parking lights and headlights were on. The driver side which I left the LED in would still flicker the HVAC unit while the lights were off, and with the lights on the driver side turn signal stayed illuminated solid and did not work.

So as of right now I put the old stock turn signal bulbs back in and everything seems to work fine (I still have the LED's in the taillights no problem there). So I'm assuming that the front LED's were possibly faulty? I'm going to order some new LED's for the fronts but if the same issue returns I'm going to be once again stumped as to what this is because I've had the LED's for about 2 years now I think and have never had issues at all.

 

It sounds as if the older Leds are going bad. I have found it has been hit and miss with some LEDs because of there resistance. Sounds like you have it under control.