I just got a 2004 Yukon xl and I am having issues with it ...I keep on getting for the past month a message on my display that's says...REDUCED ENGINR POWER... and I lose power in my motor not knowing what to do I disconnect the battery ground for 10 mins and after I connect it again the message is no longer on and everything is find but it happen today on a bumpy road my power locks unlocked my doors and then at the same time the message came up again REDUCE ENGINE POWER...has anyone had this happen if ..I think it is something in the wiring short or something but where do I start looking....PLEASE HELP ME.....