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

MODEL 166 with TRANSMISSION 724.2 

MODEL 166 with TRANSMISSION 725.0 as of model year 2016 

MODEL 292 with TRANSMISSION 725.0 

Function requirements for Downhill Speed Regulation, general 

• Vehicle speed range < 40 km/h
• Downhill Speed Regulation switched on via Downhill Speed Regulation button (N72s30)
• Set speed of the Downhill Speed Regulation (in increments of 1 km/h, from 2 to 18 km/h) possible as of transmitter key (A8/1) position ignition "ON"

Downhill Speed Regulation, general 

Downhill Speed Regulation is a system for off-road downhill speed regulation.

Downhill Speed Regulation, function sequence 

The function sequence is subdivided into the following steps:

• Downhill Speed Regulation ON/OFF, function sequence 
• Speed setting, function sequence 
• Function abort, function sequence 

Downhill Speed Regulation ON/OFF, function sequence 

The driver can switch the Downhill Speed Regulation on or off using the Downhill Speed Regulation button on 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 Downhill Speed Regulation button indicates whether the speed limiter is active. If any variable speed limiter (e.g. cruise control (CC)) is already set, it is switched off when the Downhill Speed Regulation is activated.

If the transmission mode "Offroad+" is selected, the Downhill Speed Regulation function is preselected automatically. Manual deactivation in the selected transmission mode is possible at any time using the Downhill Speed Regulation button.

Speed setting, function sequence 

The minimum Downhill Speed Regulation speed setting is approx. 2 km/h. Via the multifunction display (A1p13) in the instrument cluster (A1), the Downhill Speed Regulation speed setting can be preset in 1-km/h increments from 2 to 18 km/h using the CRUISE CONTROL lever (S40/4). The status of the speed setting is transmitted to the instrument cluster from the CRUISE CONTROL lever via steering column tube module control unit (N80), chassis CAN 1 (CAN E1), ESP® control unit, chassis CAN 1, electronic ignition lock control unit (N73) and chassis CAN 2 (CAN E2). The speed setting can also be varied while actually driving downhill.

Function abort, function sequence 

When the vehicle is accelerated by pressing the accelerator pedal (detected by the accelerator pedal sensor (B37) signal)), the Downhill Speed Regulation switches to "passive". If the vehicle speed remains below a threshold value of 45 km/h, the Downhill Speed Regulation resumes regulating the speed to the previously set speed setting. If the vehicle speed exceeds a threshold value of 45 km/h, the Downhill Speed Regulation switches off and the LED in the Downhill Speed Regulation 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-2052-97ZNA
	Overview of system components, transfer case (VG)		GF28.10-P-9998VGF