72 INSTRUMENTS AND CONTROLS
CAUTION When the inhibit position is pressed, the switch will remain in a locked position. It is important, therefore, to immediately set the switch back to the neutral position when safe to do so. Failure to set the switch back to the neutral position may result in an engine derate, clogged diesel particulate filter or damage to the filter.
DPF INHIBIT ROAD SPEED LIMITING (RSL) The DPF Smart Switch can be locked into the DOWN (or Inhibit Regen) position by the driver. If the DPF Smart Switch remains in the locked position, the following vehicle speed limiting will occur: The following label is located on the driver-side sun visor which provides additional instructions on the exhaust aftertreatment system. 1 Vehicle Moving. If vehicle is moving with the DPF Smart Switch in the locked (DOWN) position, the vehicle speed will decrease down to 16 kph (10 mph) below the current speed until the driver releases the switch back to the neutral (MIDDLE) position. 2 Vehicle Stationary and then Moving. If the vehicle is stationary with the DPF Smart Switch in the locked (DOWN) position and the driver then begins to move the truck, the vehicle speed will be limited to 16 kph (10 mph) until the driver releases the switch back to the neutral (MIDDLE) position.
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