GF30.30-P-0002KA Distronic (DTR), Function

GF30.30-P-0002KA Distronic (DTR), Function
- with CODE (219a) Distronic (DTR)
- up to 31.5.04

Component Identification:

Tasks
^ Maintaining the selected vehicle speed (cruise control function) and also regulating the distance to a vehicle ahead
^ Variable speed limiter (VSL), except United States Of America
^ controlling driver information in the instrument cluster and warning signal (distance warning).

Design
The Distronic consists of the following components:
^ Distronic control unit
^ Distronic radar sensor
^ Distronic switch block with distance potentiometer and distance warning function switch
^ Variable cruise control switch, Cruise control switch (United States Of America) (Japan)
^ Displays in instrument cluster and warning signal
^ CAN databus.

Function
The cruise control can rarely be used in dense traffic. The driver must either constantly adjust the selected speed or switch off the cruise control.

The Distronic detects the traffic situation ahead of the vehicle by means of the radar sensor located behind the radiator grille.
If the driver's own vehicle approaches another vehicle traveling at a slower speed, the speed of the driver's vehicle is reduced. The Distronic (DTR) control unit calculates the distance required and can activate the following over the CAN:
^ Increase/reduction in the specified engine speed (through ESP control unit)
^ Braking (ESP control unit)
^ Shifting gears (ETC control unit).

The Distronic can be used from a speed of approx. 30 km/h to 180 km/h or 20 to 110 mph ( United States Of America 25 to 110 mph).
If no vehicle is driving ahead, the Distronic behaves in the same way as the cruise control

The Distronic is a convenience system and not a safety system. The driver must himself brake when corresponding traffic situations arise.
The system has a diagnostic capability.

If a vehicle suddenly appears ahead (e.g. as a result of changing lanes), the Distronic attempts to take control. The braking action is, 2 however, limited to approx. 2 meters/s (equals approx. 20% of maximum braking power) for safety reasons. If more braking power is required, the driver is warned by means of an intermittent signal (accept signal).

A further audible signal (off signal) sounds if the vehicle speed drops below approx. 30 km/hour ( United States Of America 25 mph).

If the speed set with the cruise control lever is exceeded by depressing the accelerator pedal, the distance measurement of the Distronic continues to remain active even above 180 km/hour ( United States Of America 110 mph). The Distronic again controls the vehicle to the speed last set after the accelerator pedal is released.

The driver is able to influence the distance to the vehicle ahead with the distance potentiometer. The setting range equals about to 2 seconds the time distance to the vehicle ahead.

If the Distronic is switched off, the calculation of the distance continues to remain active.

The display in the instrument cluster and the intermittent signal inform the driver if the distance to the vehicle ahead is extremely close or if there is a major difference in speed to the vehicle ahead.

Visual indication (red distance warning lamp in the instrument cluster remains on) is also given if the time distance to the vehicle ahead is less than 0.8 seconds over a time period of more than 3 seconds (except United States Of America).

on AMG models the Distronic is switched off at a speed of more than 260 km/hour (160 mph) and a brief warning signal sounds. Consequently, no warning is given if the distance drops below the specified distance. The Distronic cannot be activated again until vehicle speed is less than 260 km/hour.

The variable speed limiter (VSL) is integrated in the Distronic system (except United States Of America). It is possible to switch between the functions by pressing the variable cruise control switch (S40/4).

The variable speed limiter is extended as follows in vehicles with Distronic:
^ When traveling downhill, the brakes are applied to prevent the vehicle exceeding the set speed.
^ Range of use from 10 km/hour up to the maximum vehicle speed.

Further technical data of Distronic:
^ Distance measurement range of the radar: 0 to 150 meters
^ number of radar beams: 3
^ relative speed measurement range for vehicles ahead: -50 to +200 km/hour.