Electrical tekonsha trouble

I was just wondering if anyone has had trouble with there tekonsha brake unit. Mine has gone blank as in no words or digits are visable on screen. There is still power to it as there is an orange glow all the time on the screen. Even when ute turned off. Have tested brakes by moving lever under unit and no braking on trailer working.Have tried both the van and my other trailer with no working results. Do I just throw out and start again or repairable without spending big dollars at auto elec. to be told unit is stuffed.
Thanks, Barney.

yes, will try the disconnect trick today, plus will check all connections on tekonsha and at the plug at the back of ute and at the battery. I did have to jump start friends car a couple of weeks ago and noticed battery terminal was loose (brake unit was mucking up before, then started working after tightening, for a few days) Not super good with electrics, would rather have hammer and nail or spanner in my hand.

All working again. Bad earth only so a cheap fix.It certainly pays to have a look around yourself before taking to auto elec..I wonder how much they would of charged me???