emergency blinker
the alarm
brake light switch would be most common cause
fuse, bulbs
Most likely a blown fuse
perhaps if it was loose or the conductor was cracked.
Check the dimmer switch on the floor and the electrical connection to it. It may be corroded.
Yhese are fed from different sorces so I would check the groiunds on the lights.
Check the fuses, if the fuse is blown you may have a short in the running light circuit.
BAD BRAKE LIGHT SWITCH AT TOP OF BRAKE PEDAL
The running lights have a bad ground.
If the engine isn't running, the battery is low. If the engine is running, the alternator probably has a problem. If you are wearing dark sunglasses, remove them and the lights will get brighter. good luck!
switch dead short bad wire test wires or trace system out