HSA OVRD light won't go off!

Hi, I currently work for a small company out of Chicago OTR. The owner is very poor at maintenance issues like the one I am mentioning, I have been having this light pop up along with the check engine light and I don't know why it won't go off. When it is on I cannot use cruise control. To make it go off usually I have to turn off the power switch to the battery and sit for 15 min or so but that doesn't always work and hasn't been lately. The boss always says it's nothing, well it's obviously something! I have a Freightliner cascadia evolution 2014 with 361,000 miles and it is an automatic. The light looks like a truck climbing a hill circled with a line through it exactly like the HSA OVRD switch picture but I push it and it doesn't take the light off. I know what it is for but I not even touching the button and it comes on. Is there a sensor or fuse or something I can pull see if it resets it then put it back? I mean I am desperate here driving 700+ miles a day with no cruise for any leg of the trip gets old! Any help is appreciated!