The ABS electronic control unit
M50 is supplied (at pin 2
and 6) directly by the battery via a line protected by maxifuse
F1, housed in the engine compartment junction unit B1.
The ignition-operated supply (INT/A) reaches
pin 23 from the line protected by the fuse F42 of under facia control
unit
B2
.
The control unit is earthed via pins 1 and
5.
The four sensors
K70, K71, K75, K76
send
wheel speed signals to pins 28-12, 15-16, 13-14 and 30-31 of
M50
respectively.
Brake pedal switch
I30
sends an
enablement signal to pin 14 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 37 of
M50
emits a discrete speed
signal for transmission to Body Computer
M1
; the same signal
is also copied to the CAN network.
Pins 24 and 40 of ABS control unit
M50
connect to engine control unit M10, Body Computer M1 and instrument
panel E50 to control the ABS warning light and - if the problem
lies in the EBD function - the low brake fluid level and handbrake
warning lights.
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