The brake lights on your 1999 Tahoe serve an important safety function, as they warn other drivers when you are about to come to a stop. Without working brake lights, you risk having someone rear-end you. If all your brake lights go out all at once, there is a good chance your brake switch has gone bad. The brake switch powers your brakes when you depress the pedal. Changing it yourself will take about 15 minutes.
Open the hood of your Tahoe, and remove the negative battery cable with your socket set. This will keep you from shorting out anything while you work on your SUV.
Move to where you can look beneath the driver's side dashboard where your brake pedal is. The brake light switch is mounted at the top base of the pedal.
Remove the screw that holds the clip in place holding the brake light switch. Unplug the wiring from the back of the old switch.
Insert the wiring plug back into the back of the new sensor.
Re-mount the new sensor to its retaining clip at the top base of the brake pedal. Replace the negative battery cable, and tighten it.
