To 90's Model Ford Ranger Owners

I recently got an inspection on my 1994 Ford Ranger XLT. But when my lights were tested, the brake lights did not pass inspection. When I turn on all of the lights, they all light up, including the rear tail lights. But when I step on the brakes, the brake lights do not light up, including the brake light on the back of the cab. I have checked all of the fuses and they all are good. Has anyone out there had this problem, and if so, how did you solve this problem. Another symptom I am having is once in a while the (abs) light comes on, but my brakes work fine. Now, another problem I am having with my ranger is the heater does not work. Strangely enough though, when I turn on my (AC) and move the climate control to warm, it kicks out luke warm heat when I am driving. I recently had a new radiator put in addition to a new thermostat. If anyone out there has either one of these two problems, please let me know how you solved the problems.

Thank you,

Ned