Dodge 1997 Neon WIRING DIAGRAMS, Owner'S Manual

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8W-35 ANTI-LOCK BRAKES
INDEX
page page
DESCRIPTION AND OPERATION
ABS PUMP MOTOR RELAY . . . . . . . . . . . . . . . . 6
ABS SYSTEM RELAY . . . . . . . . . . . . . . . . . . . . . 6
ABS WARNING LAMP . . . . . . . . . . . . . . . . . . . . . 6
ANTI-LOCK BRAKES . . . . . . . . . . . . . . . . . . . . . 6
BRAKE SWITCH INPUT . . . . . . . . . . . . . . . . . . . 7
DATA LINK CONNECTOR . . . . . . . . . . . . . . . . . . 7
HELPFUL INFORMATION . . . . . . . . . . . . . . . . . . 7
HYDRAULIC MODULATOR . . . . . . . . . . . . . . . . . 6
WHEEL SPEED SENSORS . . . . . . . . . . . . . . . . . 7
DESCRIPTION AND OPERATION
ANTI-LOCK BRAKES
Power for the Anti-Lock brake system is supplied
by two fuses. There is a 15 amp fuse located in the
fuse block cavity 10. This fuse supplies power to the
Controller Anti Lock Brake (CAB), and the ABS sys-
tem relay on the F12 circuit. The F12 circuit also
supplies power to the Powertrain Control Module
(PCM). Power for the fuse is supplied on the A21 cir-
cuit from the ignition switch. This fuse is HOT in the
START/RUN position.
The second fuse is located in the Power Distribu-
tion Center (PDC). It is a 40 amp fuse. This fuse is
HOT at all times and supplies power to the contact
side of the ABS pump motor relay.
There are three grounding points used in the ABS
system. One is a case ground on the CAB. The sec-
ond is the Z12 circuit at the CAB connector cavity 5.
This ground is spliced, and terminates at the left side
of the radiator closure panel.
The third ground is on the Z1 circuit. This ground
is used for the ABS hydraulic modulator, ABS system
relay, and the ABS pump motor. This ground, like the
Z12 ground splices and terminates at the left head-
lamp ground.
Additional information on the circuit function of
the ABS system is listed below. For diagnostic and
testing procedures, refer to the appropriate section of
the Service Manual or the Diagnostic Test Proce-
dures Manual.
ABS WARNING LAMP
The ABS warning lamp is an output from the Con-
troller Anti Lock Brake (CAB) and the ABS relay
box. It is used to alert the operator of a problem in
the ABS system. The G19 circuit from the CAB and
the ABS system relay is used to detect a problem. If
a problem is detected, the CAB grounds the G19 cir-
cuit and illuminates the lamp in the instrument clus-
ter.
Circuit G19 is also an output of the CAB to the
ABS system relay contact side.
ABS SYSTEM RELAY
The system relay is used for the operation of the
ABS system. Power for the relay is supplied on the
B57 circuit from cavity 57 of the Controller Anti Lock
Brake (CAB).
Ground for the relay is on the Z1 circuit. This
ground is spliced in with the pump motor and termi-
nates at the left headlamp ground.
When the system is operating normally power for
the contact side of the relay is supplied from the
CAB on the B57 circuit. It passes through the relay
to the Z1 ground and terminates at the left headlamp
ground. If a problem is detected in the system, the
contact side of the relay switches from the Z1 to the
F12 circuit. This causes the ABS warning lamp in
the instrument cluster to illuminate.
ABS PUMP MOTOR RELAY
The ABS pump motor relay controls when the
pump motor runs. Power for the coil side of the relay
is supplied from cavity 47 of the Controller Anti Lock
Brake (CAB) on the B47 circuit. This circuit also sup-
plies voltage for the contact side of the system relay.
The ground side of the coil is controlled by the B116
circuit. Circuit B116 connects to cavity 16 of the CAB
connector.
Circuit B120 from cavity 20 of the CAB connector
powers the ABS pump motor. This circuit is also used
as an input to the CAB for pump motor monitoring.
HYDRAULIC MODULATOR
The hydraulic modulator is used for the controlling
of the brake system pressure to the wheels. The mod-
ulator is made up of four solenoids.
Circuits involved are, B142 for the left front wheel,
B143 for the right front wheel, B146 for the left rear
wheel, and B148 for the right rear wheel.
The solenoids use a common ground on the Z1 cir-
cuit. There are two Z1 circuits from the modulator.
Both of these grounds terminate at the left headlamp
ground, and are spliced in with the ABS pump motor
and the ABS system relay.
8W - 35 - 6 8W - 35 ANTI-LOCK BRAKES
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