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

GF30.30-P-3001LEC Variable Speed Limiter, Function
- with CODE (239) Autonomous intelligent cruise control Plus Light
- refinement package
- as of model year 2010

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)
^ Electronic Stability Program (ESP) active (no fault message)
^ No kickdown
^ Vehicle speed ≥30 km/h
^ CC [TPM] push button (S40/4) in variable speed limiter position (LIM indicator lamp (LIMITER) is lit)

Variable Speed Limiter, general
The Variable Speed Limiter (also known as the LIMITER or SPEEDTRONIC) is an additional function of the autonomous intelligent cruise control which is integrated into the radar sensors control unit (SGR) (N62/1).
The Variable Speed Limiter enables the driver to set an individual maximum speed in the range of 30 km/h up to the maximum speed.

The signals from the CC [TPM] push button switch are detected by the steering column tube module (N80) and transmitted to the radar sensors control unit via the chassis CAN (CAN E).

The radar sensors control unit sends the selected maximum speed via the chassis CAN and central CAN (CAN F) to the instrument cluster.

The acceleration/deceleration requests are sent by the radar sensors control unit via the chassis CAN to the CDI control unit (N3/9) (for diesel engines) or ME-SFI [ME] control unit (N3/10) (for gasoline engines) and to the ESP control unitN47-5

A switching request at the automatic transmission is transmitted from the radar sensors control unit via the chassis CAN and drive train CAN (CAN C) to the ETC control unit (N15/3) (for transmission 722.6) or to the electric controller unit (VGS) (Y3/8) (for transmission 722.9).

Variable Speed Limiter, function sequence
The function sequence is described in the following steps:
^ Maximum speed function sequence
^ Activation function sequence
^ Deactivation function sequence

Maximum speed function sequence
The 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 function sequence
Pulling or moving the CC [TPM] switch up or down activates the Variable Speed Limiter. In this way 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 different degrees 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.

When the Variable Speed Limiter is activated, the segments in the electronic speedometer (A1p8) are illuminated from the beginning of the scale up to the set maximum speed. The set maximum speed is marked with an orange-colored triangle.

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

Deactivation function sequence
The Variable Speed Limiter is deactivated by:
- Moving the CC [TPM] push button to the "OFF" position
- Switchover over to autonomous intelligent cruise control Plus Light (LIM indicator lamp off)
- Kickdown (accelerator pedal pressed by >90 % and vehicle speed <20 km/h away from selected maximum speed)
- Circuit 15 OFF (ignition OFF)