Chrysler Stratus RHD 1997 Interactive Electronic Service Manual page 642

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DESCRIPTION AND OPERATION
ABS PUMP MOTOR RELAY . . . . . . . . . . . . . . . . . 7
ABS SYSTEM RELAY . . . . . . . . . . . . . . . . . . . . . . 7
ABS WARNING LAMP . . . . . . . . . . . . . . . . . . . . . 7
ANTI-LOCK BRAKES . . . . . . . . . . . . . . . . . . . . . . 7
BRAKE SWITCH INPUT . . . . . . . . . . . . . . . . . . . . 8
DESCRIPTION AND OPERATION
ANTI-LOCK BRAKES
Power for the Anti-Lock Brake (ABS) system is
supplied by three fuses. There is a 10 amp fuse
located in the Power Distribution Center (PDC) cav-
ity 10. This fuse supplies power to the Controller
Anti Lock Brake (CAB), Powertrain Control Module
(PCM) and the fuel pump relay on the F12 circuit.
Power for the fuse is supplied on the A21 circuit from
the ignition switch. This fuse is HOT when the igni-
tion switch is in the START/RUN position.
The second fuse is located in the PDC cavity 13. It
is a 40 amp fuse and used to supply power to the
ABS Pump Motor relay on circuit A10. This relay is
located in the ABS relay box. The fuse is HOT at all
times and powers the contact side of the relay.
The third fuse is also located in the PDC cavity 2.
It is a 20 amp fuse and used to power the contact
side of the ABS System relay on circuit A20. The fuse
is HOT at all times.
There are 3 grounding points used in the ABS sys-
tem. One is a case ground on the Controller Anti
Lock Brake (CAB). The second is on the Z1 circuit
from the ABS Hydraulic Modulator and the ABS
Relay Box. This ground terminates at the right frame
rail.
The third ground is also on the a Z1 circuit from
the CAB and terminates at the right frame rail.
Additional information on circuit functions of the
ABS system follows. For diagnostic and testing pro-
cedures refer to the appropriate group of the Service
Manual or the Diagnostic Test Procedures 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-
8W - 35 ANTI-LOCK BRAKES
8W-35 ANTI-LOCK BRAKES
INDEX
page
DATA LINK CONNECTOR . . . . . . . . . . . . . . . . . . . 8
HELPFUL INFORMATION . . . . . . . . . . . . . . . . . . . 8
HYDRAULIC MODULATOR . . . . . . . . . . . . . . . . . . 7
PARK BRAKE SWITCH INPUT . . . . . . . . . . . . . . . 8
WHEEL SPEED SENSORS . . . . . . . . . . . . . . . . . 8
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 right frame rail.
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 right frame
rail. If a problem is detected in the system, the con-
tact side of the relay switches from the Z1 to the A20
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 B120 circuit. This circuit also
supplies 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 B10 from the relay box 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 controlling the
brake system pressure to the wheels. The modulator
is composed 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.
8W - 35 - 7
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