you need to change the multifunctional switch
this happened to mine to
First check the fuse, or you may have a burnt out bulb
If the brake lights are not coming on in your car and you have changed the bulbs and the fuses with no results, you could also check the wiring in your '98 Chevrolet Lumina. The wires may be damaged or even broken.
Sounds like a bad brake light switch. Located above where you put your foot on the brake pedal.
its either a fuse, or the turn signal switch needs to be replaced
Try the turn signal switch in the steering column. I know it sound stupid but that is the problem and they are not cheap. At a service shop besides a dealer you are probably talking around $200+. I had the same problem, sometimes the rear brake lights would work and sometimes not but window light always worked. Good Luck
Check sockets and grounds
Its the steering colum
The fluid is added to the brake master cylinder. it is mounted under the hood on the firewall on the driver side.
the blinker switch shorted out the brake lights... really really common problem, need to replace the switch
brake light switch, it is typically located above the brake pedal somewhere on the brake pedal arm
Replace brake light switch.
Check bulbs?