Turn signals exist for one reason: to tell other drivers what you're about to do. They’re the only way you really have of communicating with other drivers, so when you send mixed signals, things can go bad quickly.
This driver found themselves confused by the big truck in front of them. While context clues helped them figure out the car’s next move, commenters pointed out that the car’s busted taillight setup would be a nightmare on the highway.
GMC Denali Turn Signal: Mixed Signals
In a viral TikTok with more than 1.2 million views, content creator @life.drop shared a weird thing he saw while driving.
The Denali truck in front of him had its left turn signal on, but the strip of lights across the rear of the truck (which seems to be a custom-installed lighting setup meant to function as a secondary turn signal) is doing something else entirely.
It flashes left. Then right. Then left again, seemingly at random, cycling through both directions while the factory signal keeps blinking.
"Can somebody tell me how the [expletive] I am supposed to interpret this?" he says in the video. "Like, what is this light setup here? What is—what is the structure of these lights?"
"BROTHER WHAT," he said in the caption.
The Denali appears to be running a custom aftermarket LED strip along its rear that may be wired incorrectly or just plain doesn't work.
Are Aftermarket Lights On Trucks Even Legal?
It depends on what they're doing and what color they are. According to Nolo, most states prohibit flashing or strobe lights on non-emergency vehicles, and that restriction applies to any lights visible from the exterior.
Beyond the flashing issue, rear-facing lights are required to be red, and brake lights must stay red with no color customization. Any light that deviates from that is generally prohibited.
The federal standard, as Trail Grid Pro explains, keeps rear lighting in the red-to-amber spectrum specifically to prevent confusion with emergency vehicles. The safest way to stay legal when upgrading any vehicle lighting is to look for DOT- or SAE-certified products. Those ratings confirm the lights meet federal brightness, color, and sizing requirements.
Installing something that isn't certified and getting pulled over doesn't just mean a fine; continued violations can result in increased penalties and potential registration revocation, and law enforcement can require you to remove the illegal lighting entirely.
Commenters React
“He goes both ways,” a top comment joked.
“It means they installed it upside down,” a person said.
“‘He’s in a left turning lane’ not every road is a left turning lane imagine seeing that on the free way,” another wrote.
Motor1 reached out to @life.drop for comment via TikTok direct message and comment. We'll be sure to update this if they respond.
@life.drop ?????? BROTHER WHAT
♬ original sound - lifedump
