The ABS electronic control unit
M50 is supplied (at pin 2
and 3) directly by the battery via a line protected by maxifuse
F5, housed in the engine compartment junction unit B1.
The ignition-operated supply (INT/A) reaches
pin 18 from the line protected by the fuse
F42 of under facia
control unit B2.The control unit is earthed at pins 1 and
4.
The four sensors
K70, K71, K75, K76 send
wheel speed signals to pins 15-16, 10-9, 17-6 and 19-8 of M50 respectively.
Brake pedal switch
I30 sends an enablement
signal to pin 20 of control unit M50: the ABS cannot intervene unless
the brake pedal is pressed.
The switch
I30
is supplied
when the ignition is switched on (INT) from fuse F37 of junction
unit
B2
.
Pin 23 di
M50 emits a discrete speed
signal that is sent tol Body Computer M1;
the same signal is
also copied via the CAN network.
Pins 15 and 26 of ABS control unit
M50
connect to engine management control unit M10, Body Computer M1
and instrument panel E50, via the CAN line, to control the ABS failure
warning light;
if the problems involve the EBD function, the
insufficient brake fluid and handbrake applied warning light comes
on in addition to the ABS failure warning light.
If the instrument panel detects a fault
in the ABS failure warning light, the general failure warning light
is lit up.
Self-diagnostic data can be read by connecting
to connector C of Body Computer
M1- pin 1: it receives signals
from pin 11 of the control unit M50 via the special diagnostic line. See E8010 DIAGNOSTIC MULTIPLE CONNECTOR