It may be a speed sensor failure. Try checking the codes with a OBD II reader. Most Auto Pats Stores will be happy to read the codes for you.
Is door ajar light on also?
If the lights come on but do not flash then the turn signal flasher relay is defective.
Pull over to your right to give them room. Flash your lights to warn them something is wrong.
Sounds like you need a new flasher.
The flashing lights are probably the factory alarm.
What year is the Ford Explorer ? There could be a separate fuse for the lower brake lights
This is because something is wrong with the vehicle. Take it in to a mechanic right away to get fixed.
More than likely the Flasher Relay is bad. If the bulbs are lit but will not flash it is definitely the Relay. This can also indicate a bad bulb on one of the lights on the side that does not flash.
Bad bulbs, bad switch located either on steering column or on transmission
one of your sensors are faulty try checking your oil sensors
Something wrong with your alarm system, like not working maybe.