DODGE NEON 1999 Service Owners Manual

BRAKE SYSTEM DIAGNOSIS CHARTS
MISCELLANEOUS BRAKE SYSTEM CONDITIONS
5 - 10 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

RED BRAKE WARNING LAMP FUNCTION
PLBRAKES 5 - 11
DIAGNOSIS AND TESTING (Continued)

POWER BRAKE SYSTEM DIAGNOSTICS
5 - 12 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

BRAKE NOISE
VEHICLE ROAD TEST
PLBRAKES 5 - 13
DIAGNOSIS AND TESTING (Continued)

DRUM BRAKE AUTOMATIC ADJUSTER
Place the vehicle on a hoist with a helper in the
driver's seat to apply the brakes. Remove the access
plug from the rear adjustment slot in each brake
support plate to provide access to the adjuster star
wheel. Then, to eliminate the possibility of maximum
adjustment, back the star wheel off approximately 10
notches. It will be necessary to hold the adjuster
lever away from the star wheel to permit this adjust-
ment.
Apply the brake pedal. This application of force
will cause the brake shoes to leave the anchor. Upon
application of the brake pedal, the lever should move
downward, turning the star wheel. Thus, a definite
rotation of the adjuster star wheel can be observed if
the automatic adjuster is working properly. If one or
more adjusters do not function properly, the respec-
tive drum must be removed for adjuster servicing.
ROTOR THICKNESS AND RUNOUT
Any servicing of the rotor requires extreme care to
maintain the rotor within service tolerances to
ensure proper brake action.
Before refinishing or refacing a rotor, the disc
should be checked and inspected for the following
conditions:
Braking surface scoring, rust, impregnation of lin-
ing material and worn ridges.
Excessive lateral runout or wobble.
Thickness variation (Parallelism).
Dishing or distortion (Flatness).
If a vehicle has not been driven for a period of
time, the rotor surface will rust in the area not cov-
ered by the brake lining and cause noise and chatter
when the brakes are applied.
Excessive wear and scoring of the rotor can cause
temporary improper lining contact if ridges are not
removed before installation of new brake pad assem-
blies.
Some discoloration or wear of the rotor surface is
normal and does not require resurfacing when lin-
ings are replaced.
Excessive runout or wobble in a rotor can increase
pedal travel due to piston knock back. This will
increase guide pin sleeve wear due to tendency of cal-
iper to follow rotor wobble.
Thickness variation in a rotor can also result in
pedal pulsation, chatter and surge due to variation in
brake output. This can also be caused by excessive
runout in rotor or hub.
Dishing or distortion can be caused by extreme
heat and abuse of the brakes.
ROTOR RUNOUT AND THICKNESS VARIATION
On vehicle rotor runout is the combination of the
individual runout of the hub face and the runout ofthe rotor. (The hub and rotor runouts are separable).
To measure runout on the vehicle, remove the wheel
and reinstall the lug nuts tightening the rotor to the
hub. Mount Dial Indicator, Special Tool C-3339 with
Mounting Adaptor, Special Tool SP- 1910 on steering
arm. Dial indicator plunger should contact braking
surface of rotor approximately one inch from edge of
rotor (Fig. 19). Check lateral runout (both sides of
rotor) runout should not exceed 0.13 mm (0.005
inch).
If runout is in excess of the specification, check the
lateral runout of the hub face. Before removing rotor
from hub, make a chalk mark across both the rotor
and one wheel stud on the high side of runout so
you'll know exactly how the rotor and hub was orig-
inally mounted (Fig. 20). Remove rotor from hub.
Install Dial Indicator, Special Tool C-3339 and
Mounting Adaptor, Special Tool SP-1910 on steering
knuckle. Position stem so it contacts hub face near
Fig. 19 Checking Rotor For Runout
Fig. 20 Marking Rotor and Wheel Stud
5 - 14 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

outer diameter. Care must be taken to position stem
outside the stud circle but inside the chamfer on the
hub rim (Fig. 21).Clean hub surface before
checking.
Runout should not exceed 0.08 mm (0.003 inch). If
runout exceeds this specification, hub must be
replaced. See Suspension Group 2. If hub runout
does not exceed this specification, install rotor on hub
with chalk marks two wheel studs apart (Fig. 22).
Tighten nuts in the proper sequence and torque to
specifications. Finally, check runout of rotor to see if
runout is now within specifications.If runout is not within specifications. Install a new
rotor or reface rotor, being careful to remove as little
as possible from each side of rotor. Remove equal
amounts from each side of rotor. Do not reduce thick-
ness below minimum thickness cast into the un-ma-
chined surface of the rotor.
Thickness variation measurements of rotor should
be made in conjunction with runout. Measure thick-
ness of rotor at 12 equal points with a micrometer at
a radius approximately 25 mm (1 inch) from edge of
rotor (Fig. 23). If thickness measurements vary by
more than 0.013 mm (0.0005 inch) rotor should be
removed and resurfaced, or a new rotor installed. If
cracks or burned spots are evident, rotor must be
replaced.
Light scoring and/or wear is acceptable. If heavy
scoring or warping is evident, the rotor must be
machined or replaced. See Brake Rotor Machining in
the Service Procedures Section in this group of the
service manual. Refer to front or rear brake rotor in
the Removal And Installation section in this group of
the service manual for the required brake rotor
replacement procedure.
Fig. 21 Checking Hub for Runout
Fig. 22 Index Rotor And Wheel Stud
Fig. 23 Checking Rotor For Thickness
PLBRAKES 5 - 15
DIAGNOSIS AND TESTING (Continued)

PROPORTIONING VALVES
PROPORTIONING VALVE TESTING SPECIAL
TOOLS
The in-line proportioning valves used on this vehi-
cle require special pressure fittings to test the pro-
portioning valves for proper proportioning valve
function. The pressure fittings are installed before
and after the proportioning valve being tested to ver-
ify proportioning valve is maintaining the required
hydraulic pressure to the rear wheel brake which it
controls.
If a condition of premature rear wheel skid occurs
on a vehicle, the proportioning valve should always
be tested prior to it being replaced. This is due to the
fact that there are conditions other then a faulty pro-
portioning valve which can cause a premature rear
wheel skid.
Testing proportioning valve pressures on a vehicle
with or without ABS requires using the same special
tools.
There are 4 Pressure Fittings, Special Tool 6805
(Fig. 24) which are used for testing both rear propor-
tioning valves mounted in the master cylinder.
The pressure gauges used for testing the new in-
line proportioning valves on both non-ABS and ABS
brakes, is Pressure Gauge Set, Special Tool C-4007-A
currently used for testing the combination valve (Fig.
25).
PROPORTIONING VALVE TESTING NON ABS
BRAKE
If premature rear wheel skid occurs on hard brake
application, it could be an indication that a malfunc-
tion has occurred with one of the proportioning
valves.
One proportioning valve controls the right rear
brake, and the other proportioning valve controls the
left rear brake (Fig. 26). Therefore, a road test todetermine which rear brake slides first is essential.
Once the wheel which slides first is determined, use
the following procedure to diagnose the proportioning
valve.
The test procedure for a premature rear wheel skid
is the same for both rear wheel proportioning valves.
The pressure test fittings used for each proportioning
valve though are different due to proportioning valve
and brake tube nut thread sizes being unique for
each rear wheel. After road testing vehicle to deter-
mine which wheel skids first, the proper test fittings
required will have to be determined. Then follow the
procedure below for testing the required proportion-
ing valve.
(1) After road testing vehicle to determine which
rear wheel exhibits premature rear wheel skid, refer
to (Fig. 26) to determine which proportioning valve
needs to be tested.
Fig. 24 Proportioning Valve Pressure Test Fittings
Fig. 25 Proportioning Valve Pressure Test Gauge
Set
Fig. 26 Non-ABS Brakes Proportioning Valve
Location On Master Cylinder
5 - 16 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

(2) Remove hydraulic brake tube (Fig. 26) from
proportioning valve controlling the rear wheel of the
vehicle which has premature wheel skid.
(3) Remove proportioning valve from that outlet
port of the master cylinder.
CAUTION: Be sure the pressure test fitting being
installed into master cylinder, has the correct
thread sizes for installation into the master cylinder
and the installation of the proportioning valve.
(4) Install Pressure Test Fitting, Special Tool
6805-1 or 6805-2 (Fig. 27) into the outlet port of the
master cylinder, which the proportioning valve was
removed from.
(5) Install proportioning valve into pressure test
fitting installed in master cylinder outlet port (Fig.
27).
CAUTION: Be sure the pressure test fitting being
installed into proportioning valve, has the correct
thread sizes for installation into the proportioning
valve and installation of brake tube fitting.
(6) Install Pressure Test Fitting, Special Tool
6805-3 or 6805-4 (Fig. 27) into the outlet port of the
proportioning valve.
(7) Connect brake hydraulic tube onto the pressure
test fitting that was installed in proportioning valve
(Fig. 27).
(8) Install a Pressure Gauge, Special Tool
C-4007-A into each pressure test fitting (Fig. 28).
Bleed air out of hose from pressure test fitting to
pressure gauge, at pressure gauge to remove all
trapped air. hose.
(9) With the aid of a helper, apply pressure to the
brake pedal until reading on proportioning valve
inlet gauge, is at the pressure shown on the followingchart. Then check the pressure reading on the pro-
portioning valve outlet gauge. If proportioning valve
outlet pressure does not agree with value shown on
the following chart, when inlet pressure shown on
chart is obtained, replace the proportioning valve. If
proportioning valve is within pressure specifications
do not replace proportioning valve.
(10) Check rear wheel brake shoe linings for con-
tamination or for replacement brake shoes not meet-
ing OEM brake lining material specifications. These
conditions can also be a possible cause for a prema-
ture rear wheel skid.
(11) Install proportioning valve in master cylinder
and hand tighten until proportioning is fully
installed and O-ring seal is seated into master cylin-
der. Then torque proportioning valve to 40 N´m (30
ft. lbs.).
(12) Install brake tube on proportioning valve.
Torque tube nut to 17 N´m (145 in. lbs.) torque.
(13) Bleed the affected brake line. See Bleeding
Brake System in the Service Adjustments section of
the manual for proper bleeding procedure
PROPORTIONING VALVE TEST WITH ABS
BRAKES
If premature cycling of the rear brake ABS occurs
on hard brake application, it could be an indication
that a malfunction has occurred with one of the pro-
portioning valves.
One proportioning valve controls the right rear
brake, and the other proportioning valve controls the
left rear brake (Fig. 29). Therefore, a road test to
determine which rear brake slides first is essential.
Once the wheel which is skidding first is determined,
Fig. 27 Proportioning Valve Installation For
Pressure Testing
Fig. 28 Pressure Gauges Installed On Pressure Test
Fittings
PLBRAKES 5 - 17
DIAGNOSIS AND TESTING (Continued)

use the following procedure to diagnose the propor-
tioning valve.
The test procedure is the same for both rear pro-
portioning valves. After road testing the vehicle to
determine which wheel skids first, follow the proce-
dure below for testing the required proportioning
valve.
(1) Using a brake pedal holding tool as shown in
(Fig. 30) depress the brake pedal past its first one
inch of travel and hold it in this position. This will
isolate the master cylinder from the brake hydraulic
system and will not allow the brake fluid to drain out
of the master cylinder reservoir.
(2) Remove the chassis brake tubes (Fig. 29) from
the proportioning valve controlling the rear wheel of
the vehicle which has premature wheel skid.
NOTE: Removal of the brake flex hose routing
bracket is required to prevent bending the chassis
brake line going to the rear brake. If the routing
bracket is not removed the chassis brake line willneed to be bent when installing the proportioning
valve with the pressure test fittings installed.
(3) Remove the brake flex hose routing bracket
from the frame.
CAUTION: Be sure the pressure test fittings being
installed into the proportioning valve have the cor-
rect thread sizes and flares for installation into the
proportioning valve and for installation of the chas-
sis brake tubes.
(4) Install Pressure Test Fitting, Special Tool
6833±1 in the inlet port of the proportioning valve
(Fig. 31). Install Pressure Test Fitting, Special Tool
8187±2 in the outlet port of the proportioning valve
(Fig. 31). Tighten tube nuts to a torque of 17 N´m
(145 in. lbs.)
(5) Install the proportioning valve in the vehicle so
that Pressure Test Fitting, Special Tool 8187±2 in
installed on the chassis brake tube going to the rear
brake (Fig. 32). Install the chassis brake tube coming
from the HCU (Fig. 32) into Pressure Test Fitting,
Special Tool 6833±1. Tighten tube nut to a torque of
17 N´m (145 in. lbs.)
(6) Install a Pressure Gauge, Special Tool
C-4007-A into each pressure test fitting (Fig. 33).
Bleed air out of hose from pressure test fitting to
pressure gauge, at pressure gauge to remove all
trapped air.
Fig. 29 Proportioning Valve Location
Fig. 30 Brake Pedal Holding Tool
Fig. 31 Pressure Test Fittings Installed On
Proportioning Valve
Fig. 32 Proportioning Valve With Pressure Test
Fittings Installed
5 - 18 BRAKESPL
DIAGNOSIS AND TESTING (Continued)

(7) With the aid of a helper, apply pressure to the
brake pedal until reading on proportioning valve
inlet gauge, is at the pressure shown on the following
chart. Then check the pressure reading on the pro-
portioning valve outlet gauge. If proportioning valve
outlet pressure does not agree with value shown on
the following chart, when inlet pressure shown on
chart is obtained, replace the proportioning valve. If
proportioning valve is within pressure specifications
do not replace proportioning valve.
(8) Check rear wheel brake shoe linings for con-
tamination or for replacement brake shoes not meet-
ing OEM brake lining material specifications. These
conditions can also be a possible cause for a prema-
ture rear wheel skid.
(9) Install proportioning valve in chassis brake
tube (Fig. 29). Tighten the proportioning valve to a
torque of 17 N´m (145 in. lbs.).
(10) Bleed the affected brake line. See Bleeding
Brake System in the Service Adjustments section of
the manual for proper bleeding procedure.
BRAKE FLUID CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts.
Swollen rubber parts indicate the presence of
petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If fluid sepa-
rates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If brake fluid is contaminated, drain and thor-
oughly flush system. Replace master cylinder, propor-
tioning valve, caliper seals, wheel cylinder seals,
Antilock Brakes hydraulic unit and all hydraulic
fluid hoses.
RED BRAKE WARNING LAMP TEST
For diagnosis of specific problems with the red
brake warning lamp system, refer to Brake System
Diagnostics Chart 2, located in the Diagnosis And
Testing section in this group of the service manual.
STOP LAMP SWITCH TEST PROCEDURE
The required procedure for testing the stop lamp
switch is covered in Group 8H, Vehicle Speed Control
System in this service manual. The electrical circuit
tests for stop lamps is covered in Group 8W Rear
Lighting in this service manual.
SERVICE PROCEDURES
BRAKE FLUID LEVEL CHECK
Check master cylinder reservoir brake fluid level a
minimum of twice a year.
Master cylinder reservoirs are marked with the
wordsFULL AND MINindicating proper range of
the master cylinder fluid level (Fig. 34).
Fig. 33 Pressure Gauges Installed On Pressure Test
Fittings
BRAKE PROPORTIONING VALVE APPLICATIONS AND PRESSURE SPECIFICATIONS
Sales CodeBrake
System
TypeSplit
PointSlopeIdentifi-
cationInlet
PressureOutlet
Pressure
BRA 149
Disc/Drum400 psi 0.43 Black
Band1000 psi 600-700
psi
BRD 149
Disc/Disc300 psi 0.34 Bar Code
Band1000 psi 550-650
psi
BRF 149
Disc/Disc
W/ABS300 psi 0.34 Bar Code
Band1000 psi 550-650
psi
PLBRAKES 5 - 19
DIAGNOSIS AND TESTING (Continued)