[ConKbot of Doom]

According to the top of the RC, a yellow RC hardware light meanse the +5v output is low. (The yellow looks like orange, they probably should have called it orange...)

Since an internal regulator outputs the 5v for the sensor lines. Either that is broken (hopefully not) or you have a short somewhere, shorting the +5v to the gnd. Un-plug all your stuff on the digital-IO and the analog ins. Then see if it is still yellow/orange. If it isn't then start plugging them back in, see which one causes the fault.

You don't have to worry about the pwm outputs, they get power from the backup battery.