2004 Jeep TJ Welding precautions

Problem- I have a large nut-cert in a frame rail that has a bolt stuck in it. The nut-cert is turning in its hole. I would like to tack weld the edge of the nut -cert to the frame with 3-4 tack welds. The threads are recessed 1/4" into the nut-cert so I think I can tack it without disturbing the threads. I will disconnect the battery. Do I need to also disconnect the ecu. Does the ecu need power to it to keep its memory? The location of the nut-cert is midway between front and rear axels on bottom side of right frame rail.