Hyundai Elantra tail lights malfunction when headlights are on, functional with parking lights on Hyundai Elantra

Some Hyundai Elantra owners report experiencing tail light malfunctions that occur only when the headlights are on, while the lights function normally with the parking lights. These issues may stem from a malfunctioning brake light switch, a faulty relay, or a blown fuse. Additionally, problems with the tail lights and blinkers could be linked to wiring defects or simple bulb replacement needs. Owners are advised to check the parking light/headlight switch, the BATT 50A fuse, and to test the tail light relay with a test light for diagnostics. It is also recommended to inspect the KEY relay when the headlights are on, verify associated fuses in the fuse box, troubleshoot the body control module for lighting system issues, and ensure that power and ground connections for the tail light circuit are secure. Addressing these potential causes can help resolve the malfunctioning tail lights in the Hyundai Elantra.