I have a 2004 Chevy Suburban that won’t go into reverse and won’t shift properly into anything but first. I’m thinking this is in what they call dummy mode and leading towards a Solenoid. My battery is from 2018 and the transmission oil is dark and needs to be replaced. I just purchased this Chevy last week so now I’m going to start doing stuff that the previous owner might have neglected. There is no check engine light tripped on the dash which is good. It doesn’t leak but I did notice the ilia mood TCM fuse under the hood does the 2004 suburban even have a TCM fuse for this year if so where do I find it? And any thoughts on the gear shifting problems along with the loss of reverse would be extremely helpful. Thanks!