GF30.30-P-3001RIA Variable Speed Limiter, Function

GF30.30-P-3001RIA Variable Speed Limiter, Function
- with CODE (219) Distronic (DTR)
- except CODE (494) USA version
- as of model year 2009

Component Identification:

Function requirements of Variable Speed Limiter in general
^ Circuit 61 ON (engine running)
^ CC [TPM] (cruise control) coded in central gateway control unit (N93)
^ ESP not deactivated
^ Vehicle speed > 30 km/h
^ Parking brake not applied
^ Selector lever in position "D"
^ CC [TPM] push button switch (S40/4) in Variable Speed Limiter position ->LIM indicator lamp is lit

If a switchover to the Variable Speed Limiter takes place at the CC [TPM] push button switch, DISTRONIC is simultaneously deactivated.

Variable Speed Limiter, general
The Variable Speed Limiter enables the driver to set a maximum speed ranging from 30 km/h up to the maximum speed.

The Variable Speed Limiter (also referred to as Limiter or SPEEDTRONIC) is an additional function of DISTRONIC that is integrated in the ESP, SPS [PML] and BAS control unit (N47-5).

Variable Speed Limiter, function sequence
The signals from the CC [TPM] push button switch are detected by the steering column tube module (N80) and transmitted to the ESP control unit over the engine compartment CAN (CAN C).
The set maximum speed is transmitted to the instrument cluster (A1) from the ESP control unit over the engine compartment CAN.

The requests for accelerating or slowing down (for engine control) are transmitted to the ME-SFI [ME] control unit (N3/10) from the ESP control unit over the engine compartment CAN.
A request to automatic transmission for shifting gears is transmitted to the ETC [EGS] control unit (N15/3) or to the electric controller unit (VGS) (Y3/8) over the engine compartment CAN.

Engine performance is reduced if the vehicle approaches the set maximum speed.
If this is inadequate, the service brake is actuated proportionately and if necessary, the automatic transmission shifts to a lower gear so that the set maximum speed is not exceeded (e.g. in case of steep declivity).

Activation
Pulling or moving the CC [TPM] push button switch up or down activates the Variable Speed Limiter. At this time, the current vehicle speed is set as the maximum speed and moving the CC [TPM] push button switch increases or decreases it.
The CC [TPM] switch can be moved up or down to increase or reduce the maximum speed in 1 km/h or 10 km/h increments (two settings).

If the Variable Speed Limiter is activated at a speed of <30 km/h, the maximum speed is automatically set to 30 km/h.

If the Variable Speed Limiter is activated, the LIM indicator lamp is lit. In addition, the text "TPM" and the set maximum speed are displayed in the left multifunction display of the instrument cluster.

Deactivation
The Variable Speed Limiter is deactivated on:
- Operating the CC [TPM] push button switch in the "OFF" position
- Switching over to DISTRONIC ->LIM indicator lamp off
- Operating the service brakes
- Operating the parking brake
- Selector level in position "N" or "R"
- ESP control intervention function
- Deactivating ESP
- Kickdown (operating the accelerator pedal >90 % and current speed <20 km/h different from the set maximum speed)
- Vehicle speed <30 km/h
- Circuit 61 OFF (engine off)