Why does one of your 98 Chevy Tahoe brake lights don't work?

Answer 1

Nonworking Brake Light

Your question implies that ONE of your brake lights does work. That being the case suggests the the problem is in just the part of the brake light circuit for the nonfunctional light.

Without doing a "hands on" troubleshooting of your vehicle no one can pinpoint the specific defect or its location. It should not be the fuse as only one fuse serves both tail light/brake light assemblies and since one light is working the fuse is OK.

However, here are a few possible causes that I can think of at the moment:

• The brake light filament in the bulb is broken or has burned out.
• The "ground" wire or its connection to the grounded sheet metal of the vehicle's body has become cut, broken, loose, or has developed a buildup of corrosion [rust] between the ground wire, or its connector, and the body sheet metal.
• A connector plug in that section of the circuit has become loose, disconnected, or corrosion or road film has built up between the metal contacts inside one of the connector plugs in that brake light's part of the circuit.
• The "hot" wire carrying electrical current to that light's assembly has become cut or disconnected.