Service Information: I/M 240 emissions testing on dynamometer
26.08.2016
Model
all
The enhanced Inspection/Maintenance emission testing program (I/M 240) is in effect in several states.
It is recommended that all vehicles be tested on a 4-wheel dynamometer.
The following vehicle may be tested on a 2-wheel dynamometer:
Mercedes-Benz vehicles that are 2WD and not equipped with Acceleration Slip Regulation (ASR)
Mercedes-Benz, Maybach and smart vehicles that are 2WD and have “Dyno-Mode” capability (must be activated)
The following vehicles must be tested on a 4-wheel dynamometer:
Mercedes-Benz vehicles equipped with ASR
Mercedes-Benz vehicles equipped with 4MATIC
Mercedes-Benz vehicles that are 2WD and do not have “Dyno-Mode” capability
Please see Attachment 1 for a list of vehicles that must be tested on a 4-wheel dynamometer.
Please see Attachment 2 for a list of vehicles with “Dyno-Mode” capability and the activation procedure.
According to US Environmental Protection Agency (EPA) procedures, if an emissions inspector has difficulty performing the I/M 240 test on a 2-wheel dynamometer, the following should be considered:
Test the vehicle on a 4-wheel dynamometer, or
Perform an optional emission test at idle +2500 rpm
An emissions inspector should also consider the options above if they are uncertain about the Dyno-Mode activation procedure or is uncertain about which vehicles can operate on a 2-wheel dynamometer.
Attachment 1: Vehicles That Must be Tested on a 4-Wheel Dynamometer
1. Ignition key on (position 1) 2. The display unit on mileage/travel (daily mileage counter and trip odometer) 3. Push reset-button R, 3 times quickly to display the workshop menu 4. Use the down arrow button to select Dynamometer Test (Rollsmode) 5. Push the + button on the steering wheel to activate Rollsmode Rollsmode stays on after every ignition event and is shown by the Info lamp with text information 6. To deactivate Rollsmode, turn the Ignition key on (position 1) and use the down arrow button to select Dynamometer Test, then push the minus () button on the steering wheel
With phone buttons: 1. Ignition key on (position 1) with driver door closed 2. The display unit on mileage/travel (daily mileage counter and trip odometer) 3. Push and hold the phone pick-up button (or hang-up button, depending on model) then within 1 sec. push and hold the OK button on the steering wheel for about 3 sec. until the workshop menu appears 4. Use the down arrow button to select Dynamometer Test (Rollsmode) and press OK Rollsmode stays on after every ignition event and is shown by the Info lamp with text information 7. To deactivate Rollsmode, turn the ignition key on (position 1) , use the OK button to select Rollsmode off when ignition off Without phone buttons: 1. (see above) 2. (see above) 3. Push and hold the + button and within 1 sec. push and hold the reset-button R for about 5 sec. until the workshop menu appears 4. Push the left upper menu button on the steering wheel until Rollsmode appears 5. Activate or deactivate Rollsmode using the R button
2007
smart (451)
1. Push and hold both buttons on the instrument panel then turn the ignition key on (position 1) and continue to hold both buttons for about 7 sec. 2. Start the engine Rollsmode is activated when the ABS, BRAKE and ESP (Traction) warning lamps are illuminated Rollsmode is deactivated when the ignition key and engine is shut off