CODE control unit
M20 is supplied at
pin 3 from the battery through the line protected by fuse F20 of
junction unit B2.
The supply controlled by the ignition (15/54)
reaches pin 8 through the line protected by fuse
F16 of B2.
Pin 4 of
M20 is earthed C10.
The line leading from pin 6 of
M20 is
a serial line leading to engine management unit M10, which is responsible
for identifying the key and exchanging codes.
The control unit is equipped with a self-diagnostic
unit that may be used by connecting the unit to connector
R10
pin 8;
it receives signals from pin 5 of control unit
M20
via the dedicated diagnostic line
See
E8010
DIAGNOSTIC MULTIPLE CONNECTOR
.
The self-diagnostic system also generates
a signal sent to the CODE fault warning light, located in instrument
panel
E50 with the signal sent from pin 2 of M20 to pin 4 of connector
C of E50.A second control unit connector is connected
via two leads to the aerial, fitted coaxially to the ignition key,
in order to detect key insertion and rotation.