What does code p2099 mean on the chevy traverse?

If You get a check engine light while driving Your Chevy Traverse You should make sure to stop driving as soon as You can to prevent excessive damage to the vehicle. When You have fully stopped somewhere safe You should use an OBD II scan tool on the car to read the codes that have been stored in Your vehicle's ECU. If You have a code P2099 that means that there is a problem with the O2 sensor after the catalytic converter on bank 2. This either means that there is a problem with the sensor, or a problem with Your catalytic converter. You should inspect the sensor and the wiring to it in order to make sure that they are free from damage or debris. If that does not solve it then I recommend replacing the sensor before replacing the cat.