Checking engine light on a brand new Hyundai Tucson - Code DTC U100800

2023 Hyundai Tucson SEL It is a new car that was purchase 2 weeks ago. Check engine light suddenly came on. Blue Link app says “DTC U100800. DTC System Powertrain DTC Sub System: EMS”
Infotainment screen says “A possible condition with your Engine Control System has been detected. A full system check is recommended to be done when convenient. Please contact your local dealership to schedule an appointment.”
Anyone familiar with DTC U100800? What can I expect a dealership tech would do?.

Unless you just stole the vehicle, it is under full warranty, take it to the Dealer… Call them and talk to the service department…


I’ve never seen that code before, but Google suggests it is related to a problem detected with car’s computer data bus system. Cars these days have several computers, all connected together by a standardized bus system. Each computer (actually the software) agrees to use the common bus to contact, transfer info between the other computers, but all abiding by the same rules so they don’t all try to talk at the same time. Most likely one of the computer’s software isn’t abiding by the rules. Likely will require a dealership software update to resolve. Which is the reason the instructions say to contact the dealership. It’s possible you are one of the first owners to have discovered this problem, and no software update is available. If so you’ll have to wait until it is.

Dealership will correct the problem. With luck they may provide a loaner car.
My recommendation, save all documentation just in case the problem can not be corrected.


Fix the problem under warranty would be my guess