I have a 01 Suburban 1500 with a serious problem. About a week and a half ago it died while idling in park. Took a few seconds but it did start again and drove with no problems. Then a few days ago it died just as I was pulling into my driveway and wouldn't start at all. I hooked up my scan tool and it showed P0706 (Transmission Range Sensor Circuit Range/Performance). I tried clearing to see if maybe it was just a bad sensor or something and it fired right up. It ran normally until yesterday when it died idling again and wouldn't start. Hooked up the tool and this time it showed U1041 (Loss of EBCM Communication) and P0335 (Magnetic Crankshaft Position Sensor Electrical Error). Tried clearning it again but it still won't start and it won't show any DTCs now. The engine will turn over when starting, but just won't actually start. With it being the same problem but different codes, I'm thinking this could the be the ECU. What do you guys think?

Thanks a lot for your advice!