Check engine light turned on, codes C1611 and C1612?

Hello, did you have the auto parts store clear the codes out? There are a few different code definitions depending on the module that actually set the code. So Advanced auto and AutoZone scan tools are usually only the type that will read codes from the engine computer (ECM). And these codes can also be stored in the Electronic Stability Control module, which works with the ABS system for traction control and braking control. It can be stored in the Tire Pressure monitoring module as C1611 Vehicle signal (VSS) time out, this has to do with modules sending an incoming message to another module in a certain amount of time.
These codes can also set in the Power Steering control module, it really has to do with a data message not being received by a certain module in the allotted time. It can be an issue with a certain connector, but for now I would have them clear the codes and see if they come back right away.
If they do, then have a full system scan of the entire vehicle for any codes stored in any module would be the next step. Hyundai service info is not that great when it comes to aftermarket information which is what we have access to.
This is an example of the code setting criteria(below). For other modules in the vehicle, it still has the same description just listing it under a different module. Here it is a signal from the ECM (engine computer) to the EPS which is the power steering module. The CAN listed above is the network the data is sent on. It's a CAN bus network. So, if they set again, it would be better to take it somewhere that has a capable scan tool and not just a basic OBD2 code reader. I know this isn't much help, but modern vehicles are full of electronic control modules now for every little thing and they all communicate on different networks throughout the vehicle.