Its a 1999 Ranger XLT ,4x4 ,4.0 , Auto. When I press on the brake pedal with the driver side turn signal on the signal quits blinking at the dash and at the tail light. It works ok on the passenger side.I checked all bulbs and they are fine. The turn signal flashes as long as the break pedal is not depressed. Any thoughts ? Thanks in advance

 

Check for a bad groung in the tailight assembly or maybe a bad bulb on that side, but most likely it is a short in the driver side tail light.

 

I'd bet on a bad mult-function switch. The switch separates the non-blinking brake light side from the blinking side so the brake light will come on solid, while the other side blinks.
Check for brake light operation and then for individual flasher operation. If both work, then the switch is the only thing I can think of that does that function.
tom

 

x2 with what tomw is saying, sounds like a bad switch.

 

doesnt this stuff pass through that connector on the rear floorboard that gets corroded easily?