Electrical Equipment and InstrumentsFunction - Electronic Cruise Control
Function The task of the electronic cruise control is to maintain a constant, set speed under changing operating conditions. The current speed is compared with the preselected value. This system deviation is used to calculate a control signal for the stepper motor integrated into the control unit for the electronic cruise control. The stepper motor influences the throttle valve position via a gearset and a Bowden cable with adjustable length. The electronic cruise control has the following options:
- Deceleration when coasting
- Step-by-step increase or decrease of currently set vehicle speed
- Resumption of previously stored vehicle speed
The cruise control is switched on and off and the desired speed set via three tip switches in the control lever. When the ignition is switched on, a self-test is performed, in which the input signals and the control unit of the electronic cruise control are checked. The cruise control can only be switched on when the test has been successfully completed. When the ignition is initialised, the cruise control memory is set to 0 km/h (0 mph). Switch on cruise control: - Actuate tip switch "I" - Actuate tip switch "R" (resumption of cruise control) If switch "R" is pressed before switch "S" after ignition ON, this is interpreted as setting, as there is no nominal value stored.
5.7.1 Function (continued) The following table lists the conditions for switching the cruise control on and off. When cruise control is activated, all conditions must be fulfilled at the same time; for switching off, only one need be fulfilled.
|
|
Switch on condition |
Switch off condition |
|
Control switch "0" |
Closed |
Open |
|
|
(switch not actuated) |
(switch actuated) |
|
Brake lamp switch |
Open |
Closed |
|
|
(brakes not actuated) |
(brakes actuated) |
|
Clutch switch (MT) |
Closed |
Open |
|
|
(clutch not actuated) |
(clutch actuated) |
|
Acceleration/deceleration |
less than 4.5 m/s 2 |
greater than 4.5 m/s 2 |
|
Selector lever position switch (AT) |
"D" "3" "2" "1" signal present |
"D" "3" "2" "1" signal not present |
|
Vehicle speed |
Higher than 25 km/h
(15 mph) and lower than 220 km/h (136 mph) |
Higher than 225 km/h
(139 mph) or lower than 16 km/h (10 mph) |
5.7.1 Function (continued) If the cruise control is switched off or has been quit via one of the above mentioned conditions, the servo motor moves to the zero position. The throttle valve is no longer actuated. Selection of individual control functions by pressing the control lever switches (cf. section 5.7.4.3 "Control Switches for Cruise Control").
|
I = |
Activate and maintain constant speed / accelerate and automatically store. |
|
|
In steps (2 km/h, 1.2 mph) or continuous increase of speed by brief |
|
|
(less than 0.5 seconds) or longer actuation (more than 0.5 seconds) of switch. |
|
|
|
|
R = |
Call up memory / deceleration and automatic storage. |
|
|
In steps or continuous deceleration with cruise control activated by brief |
|
|
(less than 0.5 seconds) or longer actuation (more than 0.5 seconds) of switch. |
|
|
|
|
0 = |
Deactivate cruise control. |
|
|
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13 Electrical
