There are five different messages which are displayed if the vehicle detects that the DEF system has been filled with a fluid other than DEF, has experienced component failures, or when tampering has been detected. The vehicle may be limited to a maximum speed of 5 mph (8 km/h) if the DEF system is not serviced within less than 200 miles (322 km) of the fault being detected.
When the DEF system needs to be serviced the following warnings will display:
Service DEF System See Dealer — This message will display when the fault is initially detected, each time the vehicle is started, and periodically during driving. The message will be accompanied by a single chime. We recommend you drive to your nearest authorized dealer and have your vehicle serviced as soon as possible.
5 MPH Max Speed in 150 mi Service DEF System See Dealer — This message will display if the DEF system has not been serviced after the “Service DEF System – See Dealer” message is displayed. This message will continuously display until the mileage counter reaches zero, and will be accompanied by a periodic chime. The message will continue to countdown until it reaches zero unless the vehicle is serviced. We recommend you drive to your nearest authorized dealer and have your vehicle serviced immediately.
Under some circumstances this mileage counter may start with a value of less than 150 miles (241 km). For example, if recurring faults are detected in a time interval of less than 40 hours, the counter may restart at the value where it stopped when a previous fault was temporarily remedied, or at a minimum of 50 miles (80 km).
5 MPH Max Speed on Restart, Long Idle or Refuel Service DEF See Dealer — This message will continuously display when the mileage counter reaches zero, and will be accompanied by a periodic chime.
The vehicle will only be capable of a maximum speed of 5 mph upon the first of the following conditions to occur:
If the vehicle is shut off and restarted.
If the vehicle is idled for an extended period of time, approximately one hour or greater.
If the system detects that the level of fuel in the tank has increased.
5 MPH Max Speed Service DEF System See Dealer — This message will continuously display, and will be accompanied by a periodic chime. Although the vehicle can be started and placed in gear, the vehicle will only operate at a maximum speed of 5 mph. Your vehicle will require towing, see an authorized dealer for service.
When this message is displayed, the engine can still be started. However, the vehicle will only operate at a maximum speed of 5 mph.
Incorrect DEF Detected See Dealer — This message will display when the fault is initially detected, each time the vehicle is started, and periodically during driving. The message will be accompanied by a single chime. We recommend you drive to your nearest authorized dealer and have your vehicle serviced as soon as possible.