773 Bobcat - Glow plug countdown & Traction Control issues

My glow plug countdown has recently started at 29.Never has been that high before, and never been more that 5 in the summer. Now the traction control lock toggles on & off. It will do a lot at lower RPM's. At higher RPM's it will only happen once in a while. I've noticed that when the traction lock toggles on & off the RPM will drop on the display screen, but you cannot hear a drop in the engine. (also, no codes pop up) Any help would be huge. Called Bobcat & they tell me it's the wiring harness or controller. I refuse to believe it. It's garage kept and worked like a champ with no problems. Why out of the blue would the harness or controller go bad?

Even well cared for machines will get corrosion on connectors and fuse holders, would be the first places to check and clean.

Traction lock can be dropping out if the parking brake pedal is partly engaged or the brake switch is going bad.
If that's not it I'd suspect a loose or corroded ground. I'd start by cleaning both battery cables on both ends. Then try to find all the ground wires(there are many) and clean the connections. While you're doing that look for any rubs or rodent chews. Next step would be to check the connectors to the controller and fuse box for moisture or corrosion.