Downhill Speed Regulation, function - GF28.19-P-3600VGC

MODEL 166 with TRANSMISSION 722.9 up to model year 2016 

Function requirements for DSR, general 

• Vehicle speed range < 40 km/h
• DSR switched on via Downhill Speed Regulation button (N72s30)
• Speed setting of DSR (in 1 km/h steps, from 2 to 18 km/h) possible as of ignition "ON"

DSR, general 

The downhill speed regulation is a downhill speed regulation off-road.

DSR, function sequence 

The function sequence is subdivided into the following steps:

• Function sequence of switch on/switch off DSR 
• Speed setting, function sequence 
• Function abort, function sequence 

Function sequence of switch on/switch off DSR 

The driver can switch the Downhill Speed Regulation on or off with the DSR button in the lower control panel control unit (N72). The "button ON" signal is received by the Electronic Stability Program control unit (N30/4). A red light-emitting diode (LED) integrated in the DSR button indicates whether the speed limiter is active. A previously set variable speed limiter (e.g. cruise control (TPM)) is switched off when the DSR is active.

If the transmission mode "Offroad 2" is selected, the DSR function is preselected automatically. Manual deactivation in the selected transmission mode is possible at any time using the DSR button.

Speed setting, function sequence 

The minimum speed setting for the DSR is approx. 2 km/h. In the multifunction display (A1p13) in the instrument cluster (A1) the speed setting of the DSR can be preadjusted in 1-km/h increments from 2 to 18 km/h using the cruise control lever (S40/4).

The speed setting can also be varied while actually driving downhill.

Function abort, function sequence 

If the vehicle is accelerated by operating the accelerator pedal, the DSR switches to "passive". If the vehicle speed remains below a threshold value of 45 km/h, the DSR resumes regulating the speed to the previously set speed setting. If the vehicle speed exceeds a threshold speed of 45 km/h, the DSR switches off and the function LED in the DSR button goes out. In addition, there is an acoustic notification and an abort report via the multifunction display in the instrument cluster.

	Electrical function schematic for Downhill Speed Regulation		PE28.19-P-2052-97NAA
	Overview of system components, transfer case (VG)		GF28.10-P-9998VGC