Gearbox Management - CITROËN DS3 R3 Max System User's Manual

An up/down demand is activated following a short bandwidth voltage detection, from one to the other (total
bandwidth : 0 to 5V). The goal of this strategy is to avoid any electrical interference from the steering wheel that
can be considered valid (shortcut, etc. ). The demand is considered from both inputs if:
Electrical diagnosis are OK (no value closed to 0 or 5 volts )
Gearbox automate at Idle state.
No hydraulic pressure measurement fault.
No barrel position measurement fault (F on dash).
No over-rev expected (downshift only), request will be saved (only one) and realised when possible.
No torque requested on downshift from driver.
200ms at least between UP requests
100ms alt least between DOWN requests
Beside the electrical diagnostic done (invalid if the voltage value is out of thresholds set), this measurement
shows the pressure available into the main circuit. This sensor is fundamental to be able to keep a eye on and
make sure the pressure is there. This is part of the pump management. In case of Hydraulic pressure drops under
30b, the pump and gearshifts change will be stopped.
The system is based on the accumulator pressure signal. In case of failure, the system will automatically switch to
the Hydraulic Block pressure signal. If both are faulty, then the pump will not be driven and the gearshift will be
stopped.
Upshift and Downshift Switches
Hydraulic pressure
System User Guide - 03.12.14
2. Driver System Overview

4. Gearbox Management

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