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Structure and function of the step
To retract and extend the step, the drive motor is energised, for a limited time, by the control unit for special
vehicles J608. At the same time, current monitoring takes place in the control unit for special vehicles J608.
If the step is blocked or fully retracted or extended, the current consumption increases and the activation of the
drive motor by the control unit for special vehicles J608 is terminated. For retraction and extension, the direction
of rotation of the drive motor is changed by reversing the polarity. In order to reliably detect that the step is fully
retracted, this is monitored by the control unit for special vehicles J608 with the aid of the button for the end
stop in the step. If retraction fails due to a blockage of the step when the engine is running, a warning tone is
sounded to alert the driver, and the function lighting in the button for the step flashes. The warning tone is
deactivated after approx. 15 seconds, the visual display continues to flash.
If the step can no longer be retracted, for example in the event of a power failure at the step, it is possible to
retract the step manually. To do this, remove the two securing clips, then unhook the two arms of the drive
mechanism underneath and fold them back. The step can then be pushed in and secured against slipping out
with the fixing clip.
For further information on manual insertion of the step and cleaning, please refer to the
manufacturer's instructions.
s599_026
Guide rail
Drive mechanism
Fixing clip
Securing clip
Button for end stop
Drive motor with bevel box
