Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality)
Diesel Exhaust Fluid (DEF) Warning Strategy (DEF Quality)
A supply of clean, fresh Diesel Exhaust Fluid (DEF) is critical for optimum Selective Catalyst Reduction (SCR) efficiency. SCR efficiency is determined by monitoring the Nitrogen Oxide (NOx) sensors located upstream and downstream of the SCR. This vehicle provides the driver with an elaborate series of prompts and warnings that are initiated when the Engine Control Module (ECM) detects a drop in the SCR NOx reduction efficiency suggesting a diluted or contaminated DEF supply.
When contaminated or diluted DEF is suspected, the ECM initiates the DEF Quality warning process. Once initiated, DEF quality warnings grow increasingly more serious as the vehicle continues to be driven. The vehicle's current DEF quality warning status is displayed on the scan tool. When a drop in SCR efficiency is detected, the normally OFF Reductant Field Quality Warning Indicator Command will display Warning Level 1 through Warning Level 11 depending on the number of miles driven. The series of DEF Quality Warnings alert the driver that DEF system service is urgently needed.
Warning Level 1
Warning Level 1 is triggered when the ECM first detects the SCR efficiency is below a calibrated value. The Driver Information Center (DIC) displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* 160 km (99 miles) until 105 km/h (65 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the mileage countdown remains displayed in the DIC. The DEF Indicator in the instrument panel is illuminated.
Warning Level 2
Warning Level 2 is triggered after the first mileage countdown expires without a DEF fluid service. The driver will hear 4 chimes on entering Warning Level 2. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Transitioning to 105 km/h (65 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the Transitioning to 105 km/h (65 mph) Max Speed remains displayed in the DIC. The DEF Indicator in the instrument panel is illuminated. Vehicle speed limit is ramping down from max speed limit to the limit of 105 km/h (65 mph).
Warning Level 3
Warning Level 2 automatically advances to Warning Level 3 after speed limit ramp down is complete or a key cycle. The driver will hear 4 chimes on entering Warning Level 3. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Speed Limited to 105 km/h (65 mph)
* 120 km (75 miles) Until 89 km/h (55 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the speed limitation and mileage countdown remains displayed on the DIC. The DEF Indicator in the instrument panel is illuminated.
Vehicle speed is limited to 105 km/h (65 mph).
Warning Level 4
Warning Level 4 is triggered after the second mileage countdown expires without a DEF fluid service. The driver will hear 4 chimes on entering Warning Level 4. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Transitioning to 89 km/h (55 mph)
The messages alternate every 5 seconds until acknowledged by the driver; however, the Transitioning to 89 km/h (55 mph) remains displayed in the DIC. The DEF Indicator in the instrument panel flashes continuously. Vehicle speed limit is ramping down from 105 km/h (65 mph) max speed limit to 89 km/h (55 mph).
Warning Level 5
Warning Level 5 is triggered after the speed limit ramp down is complete or a key cycle. The driver will hear 4 chimes on entering Warning Level 5. The series of 4 chimes will repeat 3 additional times every 3 minutes. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Speed Limited to 89 km/h (55 mph)
* 120 km (75 miles) Until 7 km/h (4 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the speed limitation and mileage countdown remains displayed in the DIC. The DEF Indicator in the instrument panel flashes continuously.
Vehicle speed is limited to 89 km/h (55 mph).
Warning Level 6
Warning Level 6 is not used.
Warning Level 7
Warning Level 7 is not used.
Warning Level 8
Warning Level 8 is not used.
Warning Level 9
Warning Level 9 is not used.
Warning Level 10
Warning Level 10 is triggered after the third mileage counter expires without a DEF fluid service. The driver will hear 4 chimes on entering Warning Level 10. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Transitioning to 7 km (4 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the Transitioning to 6 km/h (4 mph) Max Speed remains displayed in the DIC. The DEF Indicator in the instrument panel flashes continuously. Vehicle speed limit is ramping down from 89 km/h (55 mph) max speed limit to 7 km/h (4 mph).
Warning Level 11
Warning Level 11 is triggered after the speed limit ramp down is complete or a key cycle. The driver will hear 4 chimes every 3 minutes on entering Warning Level 11. The series of 4 chimes will repeat every 3 minutes. The DIC displays the following messages:
* Exhaust Fluid Quality Poor
* See Owner's Manual Now
* Speed Limited to 7 km (4 mph) Max Speed
The messages alternate every 5 seconds until acknowledged by the driver; however, the Speed Limited to 7 km (4 mph) Max Speed remains displayed in the DIC. The DEF Indicator in the instrument panel flashes continuously.
Vehicle speed is limited to 7 km/h (4 mph).