Description of operation

DESCRIPTION OF OPERATION

The electronic control unit M86 is supplied directly at pin 20 directly by the battery by a line protected by the 40A electric power assisted steering MAXI-FUSE B53; in addition, there is a supply controlled by the ignition at pin 1 via the junction unit B1 with 10A fuse F10.

A D+ signal reaches pin 12 of the electronic control unit M86 from the alternator A10 via the coupling D4.

Pin 19 of the electronic control unit M86 is connected to earth C14; a signal amplified by the instrument panel E50 connector A pin 6 reaches pin 4 of the electronic control unit M86.

The speedometer sensor K84 is connected to the instrument panel E50 amplifier via pin 9 of connector A of E50. The amplifier for the speedometer signal is supplied via pin 17 of connector A of the instrument panel E50 at the battery positive, via the line protected by 15A fuse F15 of junction unit B1 and by the 60A maxifuse B5. The speedometer sensor K84 is supplied via fuse F21 of B1, whilst it is connected to earth C10 via pin 3.

The electronic control unit M86 controls the steering electric motor N95 directly via pins 17 and 18, whilst signals reach pins 6, 7, 8, 14 from the potentiometer K58 (effort sensor) located on the steering column.

Pin 10 of connector A of the control unit M86 is connected to pin 35 of the engine management control unit M10.

The electric power assisted steering includes an autodiagnostic system; when the control unit M86 detects problems relating to the power assisted steering function, it sends a signal from pin 13 to the electric steering failure warning light in the instrument panel E50. The warning light is supplied, va connector A pin 18 of the instrument panel E50, by 10A fuse F22 of B1.

The autodiagnostic data can be read by connecting to connector R22 ; the control unit M86 sends diagnostic signals, via pin 16, to the coupling R10.

COMPONENTS