Diesel Exhaust Fluid (DEF) Warning Strategy (Anti-Tampering)

DIESEL EXHAUST FLUID (DEF) WARNING STRATEGY (ANTI-TAMPERING)
(Vehicles With VIN L, RPO LGH Only)

The reductant system supplies the Selective Catalyst Reduction (SCR) stage of the vehicle's exhaust aftertreatment system with the Diesel Exhaust Fluid (DEF) required to reduce exhaust Oxides of Nitrogen (NOx) levels. The Engine Control Module (ECM) continuously monitors the performance of the reductant system during operation.

When the conditions associated with an attempt to disable reductant system operation are detected, the ECM activates the anti-tampering feature and presents the driver with a series of prompts and warnings.

Once initiated, anti-tampering warnings grow increasingly more serious as the vehicle continues to be driven. The vehicle's current warning status is displayed on the scan tool. When tampering is suspected, the normally OFF Reductant System Malfunction Warning Indicator Command will display Warning Level 1 through Warning Level 5 depending on the number of miles driven, the number of ignition cycles, and if a refueling event was detected. The series anti-tampering warnings alert the driver that reductant system service is urgently needed.

Warning Level 1
Warning Level 1 is triggered when the ECM first detects an abnormal value on a reductant system circuit. The Driver Information Center displays the following messages:

• Service Exhaust Fluid System
• See Owner's Manual Now

The messages remain on the Driver Information Center until acknowledged by the driver. The DEF Indicator in the instrument panel is illuminated.

Warning Level 2
Warning Level 2 is triggered when the distance driven since receiving the first Service Exhaust Fluid System, message exceeds approximately 805 km (500 mi). The driver will hear 4 chimes on entering Warning Level 2. The Driver Information Center displays the following messages:

• Service Exhaust Fluid System
• See Owner's Manual Now

• 89 km/h (55 mph) Max Speed on Restart

The messages alternate every 5 seconds until acknowledged by the driver; however, the 89 km/h (55 mph) Max Speed on Restart, remains displayed on the Driver Information Center. The DEF Indicator in the instrument panel is illuminated.

The system will advance from Warning Level 2 to either Warning Level 3 or Warning Level 4 depending on whether the ECM detects that additional fuel was added. The system advances to Warning Level 3 at the next ignition cycle if no fueling event was detected or to Warning Level 4 if additional fuel was added during the current ignition cycle.

Warning Level 3
Warning Level 2 automatically advances to Warning Level 3 at the next ignition cycle. The driver will hear 4 chimes on entering Warning Level 3. The series of 4 chimes is repeated 3 times during each successive ignition cycle. The Driver Information Center displays the following messages:

• Service Exhaust Fluid System
• See Owner's Manual Now
• Speed Limited to 89 km/h (55 mph)

The messages alternate every 5 seconds until acknowledged by the driver; however, the Speed Limited to 89 km/h (55 mph), remains displayed on the Driver Information Center. The DEF Indicator in the instrument panel flashes continuously.

Vehicle speed is limited to 89 km/h (55 mph).

Warning Level 4
Warning Level 4 is triggered when the distance driven since receiving the first warning message exceeds 3,218 km (2,000 mi). The driver will hear 4 chimes on entering Warning Level 4. The series of 4 chimes will repeat 3 times during each successive ignition cycle. The Driver Information Center displays the following messages:

• Service Exhaust Fluid System
• See Owner's Manual Now
• Speed Limited to 89 km/h (55 mph)
• 6 km/h (4 mph) Max Speed at Next Fuel Fill

The messages alternate every 5 seconds until acknowledged by the driver; however, the Speed Limited to 89 km/h (55 mph), and 6 km/h (4 mph) Max Speed Next Fuel Fill, remain alternately displayed on the Driver Information Center. The DEF Indicator in the instrument panel flashes continuously.

Vehicle speed is limited to 89 km/h (55 mph).

Warning Level 5
Warning Level 4 automatically advances to Warning Level 5 when ECM detects a fuel fill event. The driver will hear 4 chimes on entering Warning Level 5. The series of 4 chimes will repeat every 3 minutes until the vehicle is serviced. The Driver Information Center displays the following messages:

• Service Exhaust Fluid System
• See Owner's Manual Now
• Speed Limited to 6 km/h (4 mph).

The messages alternate every 5 seconds until acknowledged by the driver; however, the Speed Limited to 6 km/h (4 mph), remains displayed on the Driver Information Center. The DEF Indicator in the instrument panel flashes continuously.

Vehicle speed is limited to 6 km/h (4 mph) maximum.