I have a 2007 Silverado 1500 LS crew cab 4.8. The gauges sometimes go on and off. The caution lights flash on and off sometimes. Right now the a/c , door locks , window wipers and the mirrors don't work . the alternator , battery , fuses , relays and battery ground cable all check out fine. After working on it today suddenly every thing works fine now. Could the BCM be causing these problems ? Does anybody know what this might be ? <!-- / message -->