A Coat of Paint Gone Wrong: The Bizarre Reason Genesis G90s Are Braking Themselves

It’s a well-known fact that technology, for all its advancements, is rarely perfect. Automakers and their suppliers work tirelessly to refine these systems and ensure they are problem-free, but glitches can still slip through the cracks. These are often referred to as ‘false positives’—errors that can lead to production recalls until a solution is found. A recent case involving the Genesis G90 in the United States is a perfect, if unusual, example.

While the Genesis G90 might be unfamiliar to some, it stands as one of the most luxurious and impressive models from Hyundai’s premium brand. Positioned as a rival to the exclusive Mercedes-Benz S-Class, it boasts ample space and some of the world’s most advanced comfort and safety systems. However, such a high dose of technology can sometimes lead to unexpected issues, and the one affecting this luxury model is being described as a ‘strange phenomenon’.

Even a Luxury Sedan Like the G90 Isn’t Immune to Flaws

The issue first came to the attention of the National Highway Traffic Safety Administration (NHTSA) in February of this year. The agency received a report that the luxury sedan’s Highway Driving Assist system was activating its emergency braking function without any warning or detection of objects ahead. This type of malfunction poses a significant risk not only to the occupants of the Genesis but also to the vehicles following behind.

Typically, a malfunction in the radar sensors installed in the front bumper would be the prime suspect. Yet, even after replacing the sensors, the problem persisted. This led Genesis, which was forced to halt production for several months, to dig deeper. Their investigation uncovered a startling fact: the system failure was only occurring on vehicles with a specific body paint—’Savile Silver’.

Further testing confirmed that this specific paint was indeed the root cause of the malfunction. The problem lies in the paint’s high concentration of aluminum particles, which interfere with the signals from the radar sensors located in the front corners. Essentially, the signals were reflecting off the paint itself.

When Radar Sensor Detection Goes Awry

The NHTSA has identified two specific situations where this failure occurs. The first is when the sensors are exposed to strong sunlight, which intensifies the reflection and tricks the system into believing it has detected an object in the adjacent lane, triggering the brakes to avoid a potential collision. The second scenario happens when the Highway Driving Assist is engaged at speeds up to 20 km/h (about 12 mph) or when the lane change assistant is activated with the turn signal to initiate a maneuver.

Given the Genesis G90’s hefty price tag—around €112,000 in Germany—the number of affected vehicles is relatively small. The US safety agency has identified 483 units impacted by the issue. These vehicles have either been recalled, or their owners have been instructed not to use the Highway Driving Assist feature. The solution involves applying a sealant to the front beam beneath the bumper to prevent radar transmission through the structure. It’s a stark reminder of how something as seemingly simple as a coat of paint can throw sophisticated electronics into chaos.