ELECTRIC STEERING - OPERATIONAL DESCRIPTION

Operational description

The electrohydraulic power assisted steering control unit M86 controls and regulates the electrically operated steering system.

The direct power supply for the control unit arrives from the battery via the line protected by maxifuse F6 of the maxifuse case on battery B99 at pin A of connector A of M86. Pin B of connector A of M86 is earthed.

The ignition-operated power supply arrives via a line protected by fuse F21 of Body Computer M1 at pin 1 of connector B of M86.

Body Computer M1 - connector G - is supplied directly from the battery from a line protected by maxifuse F2 of engine compartment control unit B1. It is ignition-operated (INT) at pin 32 of connector D. Pin 10 of connector H of M1 supplies a reference earth to the Body Computer.

Control unit M86 is connected via the CAN - pin 7 and 8 of connector B - to the other nodes and in particular Body Computer M1 and instrument panel E50, to which it sends signals for the electric power steering warning light and the CITY function activation signal.

The CITY function selection button (less effort to turn the steering wheel) is located in the control unit in the centre of the facia H90: the activation earth signal is received from Computer M1, pin 49 of connector D while the CITY function activation signal is sent to pin 28 of the same connector.