Dodge RAM TRUCK 1500 1995 Service Manual page 627

8W - 32 - 2
8W-32 REAR WHEEL ANTI-LOCK BRAKES
B R
REAR ANTI-LOCK VALVE
The rear anti-lock valve contains an isolation sole­
noid, a dump solenoid and a reset switch. Each is
powered by the Rear Wheel Anti-Lock (RWAL) mod­
ule on separate circuits.
Circuit B108 from cavity 14 of the RWAL module
feeds the dump solenoid. The isolation solenoid is
powered on circuit B101 from cavity 1 of the RWAL
module. Circuit Z8 provides ground for both sole­
noids.
Circuit B i l l from cavity 11 of the RWAL module
connects to the reset switch. The case grounded rear
anti-lock valve provides ground for the reset switch,
FOUR-WHEEL DRIVE SWITCH SENSE
From circuit G107, the Rear Wheel Anti-Lock
(RWAL) module senses when the four-wheel drive/
PTO indicator lamp switch CLOSES. Circuit G107
connects to cavity 4 of the RWAL module.
WARNING LAMP
The Rear Wheel Anti-Lock (RWAL) module pro­
vides ground for the instrument cluster Check Anti-
Lock warning lamp on circuit G19. Circuit F14
provides voltage to the instrument cluster to feed the
warning lamp.
DATA LINK CONNECTOR
Circuit B112 from cavity 10 of the Rear Wheel An­
ti-Lock (RWAL) module connects to the RWAL data
link connector. System fault codes can be read by mo­
mentarily grounding the RWAL diagnostic connector.
Refer to Group 5, Brakes, for more information.
PARI BRAIE SWITCH INPUT
On circuit G i l , the Rear Wheel Anti-Lock (RWAL)
module senses when the park brake switch CLOSES.
Circuit G i l from the park brake switch connects to
cavity 5 of the RWAL module.
BRAKE WARNING LAMP SWITCH INPUT
Circuit G9 from provides an input to the Rear
Wheel Anti-Lock (RWAL) control module. The module
receives the input when either the ignition switch is
in the START position, or the park brake warning
lamp switch in the hydraulic combination valve
closes.
STOP LAMP SWITCH INPUT
Circuit V40 provides an input to the Rear Wheel
Anti-Lock (RWAL) control module as to when the op­
erator is applying the brakes. The V40 circuit con­
nects to cavity 7 of the RWAL control module.
VACUUM SWITCH
The vacuum switch is' used on the diesel engine
only. Power for the switch is supplied on circuit A20.
This circuit is HOT in the RUN position only and
protected by a 20 amp fuse located in cavity 14 of the
fuse block. Ground for the switch is supplied on cir­
cuit Zl.
Circuit G9 connects to the vacuum switch and sup­
plies a ground path for circuit G9. If there is a prob­
lem in the system, the switch grounds circuit G9 and
the red brake warning lamp in the instrument clus­
ter is illuminated.
DIAGRAM INDEX—REAR WHEEL ANTI-LOCI
1RAIES
Component ^ ^ Page
4WD Switch" .~~ . T ~ . 8W-32-7
Brake Warning Switch .8W-32-5
Data Link Connector . . . . . . . . . . . . . . . . . . . . . .8W-32-8
Daytime Running Lamp (DRL) Module . . . . . . . . . . .8W-32-7
Fuse 2 (PDC) . . .8W-32-5
Fuse 6 (PDC) 8W-32-6
Fuse 14 (Fuse Block) .8W-32-5
Fuse 20 (Fuse Block) . 8W-32-6
Ignition Switch .8W-32-5
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . .8W-32-7
Powertrain Control Module . .8W-32-6
PTO Switch .8W-32-7
Rear Anti-Lock Valve .8W-32-8
Rear Wheel Anti-Lock Brake Sensor .8W-32-8
RWAL Control Module 8W-32-5, 6, 7, 8
Vacuum Sensor .8W-32-5