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Dodge Viper SRT-10 (ZB). Manual - part 43

(1) Make sure all hydraulic fluid lines are installed

and properly torqued.

(2) Connect the DRBIII

t scan tool to the Data

Link Connector. The connector is located under the
lower instrument panel to the left of the clutch pedal.

(3) Using the DRBIII

t, check to make sure the

CAB does not have any fault codes stored. If it does,
clear them using the DRBIII

WARNING: WHEN BLEEDING THE BRAKE SYSTEM
WEAR SAFETY GLASSES. A CLEAR BLEED TUBE
MUST BE ATTACHED TO THE BLEEDER SCREWS
AND SUBMERGED IN A CLEAR CONTAINER FILLED
PART WAY WITH CLEAN BRAKE FLUID. DIRECT
THE FLOW OF BRAKE FLUID AWAY FROM YOUR-
SELF AND THE PAINTED SURFACES OF THE VEHI-
CLE. BRAKE FLUID AT HIGH PRESSURE MAY
COME OUT OF THE BLEEDER SCREWS WHEN
OPENED.

(4) Bleed the base brake system using the stan-

dard pressure or manual bleeding procedure. (Refer
to 5 - BRAKES - BASE - STANDARD PROCEDURE)

(5) Using

the

DRBIII

select

ANTILOCK

BRAKES,

followed

MISCELLANEOUS,

then

BLEED BRAKES. Follow the instructions displayed.
When the scan tool displays TEST COMPLETED,
disconnect the scan tool and proceed.

(6) Bleed the base brake system a second time.

Check brake fluid level in the reservoir periodically
to prevent emptying, causing air to enter the hydrau-
lic system.

(7) Fill the master cylinder reservoir to the full

level.

(8) Test drive the vehicle to be sure the brakes are

operating correctly and that the brake pedal does not
feel spongy.

SPECIFICATIONS

ANTILOCK BRAKE SYSTEM FASTENER
TORQUE

DESCRIPTION

N·m

Ft.

Lbs.

In.

Lbs.

Brake Tube Nuts

145

CAB Mounting Bolts

—

ICU Mounting Bolts

—

Tone Wheel (Front) Mount-
ing Bolt

150

Wheel Speed Sensor Head
Mounting Bolt

—

100

TONE WHEEL RUNOUT

FRONT TONE WHEEL:

Maximum Runout

0.37 mm (0.015 in.)

REAR TONE WHEEL:

Maximum Runout

0.37 mm (0.015 in.)

WHEEL SPEED SENSOR AIR GAP

DESCRIPTION

SPECIFICATION

FRONT SENSOR

0.127 – 1.20 mm

0.005 – 0.047 in.

REAR SENSOR

0.127 – 1.20 mm

0.005 – 0.047 in.

TONE WHEEL

REMOVAL - FRONT TONE WHEEL

NOTE: Review all Warnings and Cautions. (Refer to
5 - BRAKES - WARNING)

(1) Raise vehicle. (Refer to LUBRICATION &

MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)

(2) Remove wheel and tire assembly. (Refer to 22 -

TIRES/WHEELS - REMOVAL)

(3) Remove brake caliper from knuckle and brake

rotor and hang out of the way. (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/BRAKE PADS/SHOES
- REMOVAL)

(4) Using hex wrench or driver socket, remove

screw retaining tone wheel to hub and bearing (Fig.
1).

(5) Remove tone wheel.

INSPECTION - TONE WHEEL

Tone wheels can cause erratic wheel speed sensor

signals. Inspect tone wheels for the following possible
causes.

• missing, chipped, or broken teeth

• contact with the wheel speed sensor

• wheel speed sensor to tone wheel alignment

• wheel speed sensor to tone wheel clearance

• excessive tone wheel runout

• tone wheel loose on its mounting surface
Rear tone wheels are pressed onto their mounting

surfaces and should not rotate independently from
the mounting surface.

If a front tone wheel is found to need replacement,

the tone wheel can be replaced as a separate compo-
nent. (Refer to 5 - BRAKES/ELECTRICAL/TONE
WHEEL - REMOVAL)

5 - 50

BRAKES - ABS

BRAKES - ABS (Continued)

If a rear tone wheel is found to need replacement,

the axle shaft must be serviced. No attempt should
be made to replace just the tone wheel. (Refer to 3 -
DIFFERENTIAL

DRIVELINE/HALF

SHAFT/

AXLE SHAFT - REMOVAL)

Check the gap between the speed sensor head and

the tone wheel to ensure it is within specifications.
(Refer to 5 - BRAKES - ABS - SPECIFICATIONS)

Excessive wheel speed sensor runout can cause

erratic wheel speed sensor signals. For the maximum
allowed tone wheel runout specification, (Refer to 5 -
BRAKES - ABS - SPECIFICATIONS). If front tone
wheel runout is excessive, determine if it is caused
by a defect in the tone wheel or hub and bearing. If
rear tone wheel runout is excessive, determine if it is
caused by a defect in the axle shaft assembly or hub
and bearing. Replace as necessary.

INSTALLATION - FRONT TONE WHEEL

(1) Make sure mating surface of tone wheel and

hub and bearing is clean.

(2) Install tone wheel through the seal on rear of

knuckle and against rear of hub and bearing assem-
bly (Fig. 1).

(3) Using same bolt or identical replacement bolt,

mount tone wheel to hub and bearing. Tighten bolt to
17 N·m (150 in. lbs.) torque.

(4) Verify proper wheel speed sensor-to-tone wheel

air gap. (Refer to 5 - BRAKES - ABS - SPECIFICA-
TIONS)

(5) Install brake caliper. (Refer to 5 - BRAKES/HY-

DRAULIC/MECHANICAL/BRAKE

PADS/SHOES

INSTALLATION)

(6) Install tire and wheel assembly (Refer to 22 -

TIRES/WHEELS - INSTALLATION). Progressively
tighten the wheel mounting nuts in the proper
sequence to 122 N·m (90 ft. lbs.) torque.

(7) Lower vehicle.
(8) Road test vehicle to ensure proper operation of

base and antilock brakes.

WHEEL SPEED SENSOR -
FRONT

REMOVAL

NOTE: Before proceeding review Warnings and
Cautions. (Refer to 5 - BRAKES - WARNING) (Refer
to 5 - BRAKES - CAUTION).

(1) Raise vehicle. (Refer to LUBRICATION &

MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).

(2) Remove wheel and tire assembly. (Refer to 22 -

TIRES/WHEELS - REMOVAL)

(3) Disconnect vehicle wiring harness from wheel

speed sensor wiring connector at frame rail.

(4) Remove sensor wiring connector clip from

frame rail.

(5) Remove sensor harness from routing clips

along brake flex hose.

(6) Remove bolt fastening sensor head to steering

knuckle (Fig. 2).

CAUTION: When removing a wheel speed sensor
from the knuckle, do not use pliers on the sensor
head. This may damage the sensor head. If the sen-
sor has seized, use a hammer and a punch to tap
the edge of the sensor head ear, rocking the sensor
side-to-side until free.

(7) Carefully remove sensor head from steering

knuckle.

INSTALLATION

CAUTION: Failure to install wheel speed sensors
properly may result in contact with moving parts or
an over extension of wires causing an open circuit.
Be sure that sensor harnesses are installed, routed,
and clipped properly.

Fig. 1 Tone Wheel Mounting

1 - SEAL
2 - HUB AND BEARING
3 - KNUCKLE
4 - TONE WHEEL
5 - MOUNTING BOLT

BRAKES - ABS

5 - 51

TONE WHEEL (Continued)

(1) Install wheel speed sensor head in steering

knuckle and install mounting bolt (Fig. 2). Tighten
mounting bolt to 11 N·m (100 in. lbs.) torque.

(2) Route sensor harness along brake flex hose and

install it in routing clips.

(3) Push sensor connector fastener clip into mount-

ing hole in frame rail.

(4) Connect vehicle wiring harness to sensor con-

nector.

(5) Install tire and wheel assembly (Refer to 22 -

TIRES/WHEELS - INSTALLATION). Progressively
tighten the wheel mounting nuts in the proper
sequence to 122 N·m (90 ft. lbs.) torque.

(6) Lower the vehicle.
(7) Road test vehicle to ensure proper operation of

base brakes and ABS.

WHEEL SPEED SENSOR -
REAR

REMOVAL

NOTE: Before proceeding, review Warnings and
Cautions. (Refer to 5 - BRAKES - WARNING) (Refer
to 5 - BRAKES - CAUTION)

(1) Raise vehicle. (Refer to LUBRICATION &

MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).

(2) Remove wheel and tire assembly. (Refer to 22 -

TIRES/WHEELS - REMOVAL)

(3) Disconnect vehicle wiring harness from wheel

speed sensor wiring connector at frame rail.

(4) Remove fastener clip securing sensor connector

to frame rail.

(5) Open routing clips along parking brake cable

and remove sensor harness.

(6) Remove bolt fastening sensor head to knuckle

(Fig. 3).

(7) Carefully remove sensor head from knuckle.

INSTALLATION

CAUTION: Failure to install speed sensor properly
may result in contact with moving parts or an over
extension of wires causing an open circuit. Be sure
that sensor harnesses are installed, routed, and
clipped properly.

(1) Install wheel speed sensor head in knuckle and

install mounting bolt (Fig. 3). Tighten mounting bolt
11 N·m (100 in. lbs.) torque.

(2) Route sensor harness along parking brake

cable and install routing clips. Close clips.

Fig. 2 Front Wheel Speed Sensor Mounting

1 - KNUCKLE
2 - WHEEL SPEED SENSOR
3 - MOUNTING BOLT

Fig. 3 Rear Wheel Speed Sensor Mounting

1 - MOUNTING BOLT
2 - WHEEL SPEED SENSOR

5 - 52

BRAKES - ABS

WHEEL SPEED SENSOR - FRONT (Continued)

(3) Push sensor connector fastener clip into mount-

ing hole in frame rail.

(4) Connect vehicle wiring harness to sensor con-

nector.

(5) Install tire and wheel assembly (Refer to 22 -

TIRES/WHEELS - INSTALLATION). Progressively
tighten the wheel mounting nuts in the proper
sequence to 122 N·m (90 ft. lbs.) torque.

(6) Lower vehicle.
(7) Road test vehicle to ensure proper operation of

base brakes and ABS.

HCU (HYDRAULIC CONTROL
UNIT)

DESCRIPTION - HYDRAULIC CONTROL UNIT
(HCU)

The hydraulic control unit (HCU) is mounted to

the CAB as part of the ICU (Fig. 6). The HCU con-
trols the flow of brake fluid to the brakes using a
series of valves and accumulators. A pump/motor is
mounted on the HCU to supply build pressure to the
brakes during an ABS stop.

VALVES AND SOLENOIDS

The valve block contains three inlet valves and

three outlet solenoid valves. The inlet valves are
spring-loaded in the open position and the outlet
valves are spring-loaded in the closed position during
normal braking. The fluid is allowed to flow from the
master cylinder to the wheel brakes.

During an ABS stop, these valves cycle to maintain

the proper slip ratio for each wheel. The inlet valve
closes preventing further pressure increase and the
outlet valve opens to provide a path from the wheel
brake to the HCU accumulators and pump/motor.
This releases (decays) pressure from the wheel brake,
thus releasing the wheel from excessive slippage.
Once the wheel is no longer slipping, the outlet valve
is closed and the inlet valve is opened to reapply
(build) pressure.

BRAKE FLUID ACCUMULATORS

There are two fluid accumulators in the HCU: one

for the primary hydraulic circuit, and one for the sec-

ondary hydraulic circuit. Each hydraulic circuit uses
a 3 cc accumulator.

The fluid accumulators temporarily store brake

fluid that is removed from the wheel brakes during
an ABS cycle. This stored fluid is used by the pump/
motor to provide build pressure for the brake hydrau-
lic system. When the antilock stop is complete, the
accumulators are drained by the pump/motor.

PUMP/MOTOR

There are two pump assemblies in the HCU: one

for the primary hydraulic circuit, and one for the sec-
ondary hydraulic circuit. Both pumps are driven by a
common electric motor (Fig. 6). This DC-type motor
is integral to the HCU and is controlled by the CAB.

The pump/motor provides the extra amount of

brake fluid needed during antilock braking. Brake
fluid is released to the accumulators when the outlet
valve is opened during an antilock stop. The pump
mechanism consists of two opposing pistons operated
by an eccentric camshaft. In operation, these pistons
are used to purge fluid from the accumulators back
into the master cylinder circuits. When the antilock
stop is complete, the pump/motor drains the accumu-
lators.

The CAB may turn on the pump/motor when an

antilock stop is detected. The pump/motor continues
to run during the antilock stop and is turned off after
the stop is complete. Under some conditions, the
pump/motor runs to drain the accumulators during
the next drive-off.

The pump/motor is not a serviceable item; if it

requires replacement, the HCU must be replaced.

OPERATION - HYDRAULIC CIRCUITS AND
VALVES

The hydraulic fluid control valves within the HCU

control the flow of pressurized brake fluid to the
wheel brakes during the different modes of ABS
braking. The following paragraphs explain how this
works. For purposes of explanation only, it is
assumed that only the right front wheel is experienc-
ing antilock braking; the following diagrams show
only the right front wheel in an antilock braking
operation.

BRAKES - ABS

5 - 53

WHEEL SPEED SENSOR - REAR (Continued)

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