Had a previous '99 Cherokee (which I killed flipping it down a mountainside...); on '99.2; previous had this same issue: when the airbag light comes on, 1) all the gauges die, 2) the little ones (4) stay live but the tach/speedo die, or 3) they all come and go whenever they feel like it. Any idea what's going on and how to solve this? Many thanks.