LR3/Disco 3
Seat and mirror motors are deemed to have stalled if there is no change in the inputs that are received from the
corresponding feedback sensors for 200ms while that axis is being driven.
If a stall condition is detected then the drive to that axis is cancelled for the remainder of that memory operation (memory
recall) or until the switch is re-selected (manual movement).
If the motor movement has stopped due to loss of sensor feedback, either stall or sensor failure, then that axis may be
activated again, to move past the stall position, by re-selecting the appropriate switch. This allows control of the motor to
be maintained if sensor feedback is lost.
Upon re-selection of movement, if sensor pulses are detected then the motor will continue to be driven until the switch is
released or another stall condition is detected. If sensor feedback is not detected then the motor is only driven for 0.5
second and then stops until the switch is released and then pressed again, when a further 0.5 second of activation is
permitted, and so on.
For all seat motor manual movements, whenever a motor is driven and a stall occurs, the memory control module records
the position at which the stall occurred. If movement occurs beyond a stall position, then that position is erased from the
control modules memory. This will always allow movement past a previously recorded stall position once movement has
been registered beyond that position. This is the case for both manual and memory movement.
Initialisation
When a replacement memory control module is fitted to a seat it should be initialised so that the control module can learn
the seats maximum and minimum adjustment values. This is achieved by adjusting all seat movement axis from one end
of travel to the other; slide, recline, height and tilt.
Battery Monitor
If the battery voltage drops below 10.5 Volts, then the memory control module ignores all requests for a memory recall,
including lazy entry, until the battery voltage has reached 11.5 Volts. This will conserve as much power in the vehicle
battery as possible to enable engine cranking.
Stand-by Mode
The memory control module supports a stand-by mode to keep power consumption to a minimum.
The control module will enter stand-by mode upon receipt of LIN bus 'SLEEP' message from the Central Junction Box
(CJB) or, alternatively, a time period of 3 seconds after the LIN bus network has remained quiet provided there are no
motors being driven at that time and there are no valid switch requests.
If there is a failure with the LIN bus network then the control module will enter stand-by mode and remain there until
communication is restored. The seat will be operational in 'inch mode' only if there is a LIN bus failure.
If the control module is being prevented from entering stand-by mode due to motor movement, memory recall or switch
operation, then it will enter stand-by mode when the current function has terminated.
NOTE :
The control module will exit stand-by mode if there is any LIN bus activity. When the control module exits stand-by mode it
must verify the 'System Enable Status' in order to recognise when it should respond to a switch request.
SEAT HEATING
In the case of a memory recall, all memory recall operations should be carried out before entering stand-by mode,
not just the current motor movement.