1999 DODGE NEON Service Repair Manual

either through the park brake switch, the fluid level
sensor in the master cylinder reservoir, or the igni-
tion switch in the crank position.
The Brake Fluid Level sensor is located in the
brake fluid reservoir of the master cylinder assembly
(Fig. 18). The purpose of the sensor is to provide the
driver with an early warning that the brake fluid
level in the master cylinder reservoir has dropped to
below normal. This may indicate an abnormal loss of
brake fluid in the master cylinder fluid reservoir
resulting from a leak in the hydraulic system.
As the fluid drops below the minimum level, the
fluid level sensor closes the brake warning light cir-
cuit. This will turn on the red brake warning light.
At this time, master cylinder fluid reservoir shouldbe checked and filled to the full mark with DOT 3
brake fluid.If brake fluid level has dropped in
master cylinder fluid reservoir, the entire
brake hydraulic system should be checked for
evidence of a leak.
STOP LAMP SWITCH
The stop lamp switch controls operation of the
vehicles stop lamps. Also, if the vehicle is equipped
with speed control, the stop lamp switch will deacti-
vate speed control when the brake pedal is
depressed.
The stop lamp switch controls operation of the
right and left tail, stop and turn signal lamp and
CHMSL lamp, by supplying battery current to these
lamps.
The stop lamp switch controls the lamp operation
by opening and closing the electrical circuit to the
stop lamps.
REAR WHEEL HUB/BEARING
CAUTION: If a vehicle is equipped with antilock
brakes the tone wheels for the rear wheel speed
sensors are pressed onto the hub. The tone wheels
used on this vehicle equipped with the Teves Mark
20 Antilock Brake System are different then those
used on past models of this vehicle equipped with
antilock brakes. Reduced braking performance will
result if this part is used on earlier model vehicles
and an accident could result. Do not use on
pre-1998 model year vehicles.
All vehicles are equipped with permanently lubri-
cated and sealed for life rear wheel bearings. There
is no periodic lubrication or maintenance recom-
mended for these units. However, if servicing of a
rear wheel bearing is required, refer to procedures in
the diagnosis and testing section and the removal
and installation section in this group of the service
manual for the inspection and replacement of the
rear wheel bearing.Fig. 17 Power Brake Booster Assembly
Fig. 18 Master Cylinder Fluid Level Sensor
5 - 8 BRAKESPL
DESCRIPTION AND OPERATION (Continued)

DIAGNOSIS AND TESTING
BRAKE SYSTEM BASIC DIAGNOSIS GUIDE
SYMPTOMCHART 1
MISC.
COND.CHART 2
WARNING
LIGHTCHART 3
POWER
BRAKESCHART 4
BRAKE
NOISECHART 5
WHEEL
BRAKES
Brake Warning Light On X NO NO
Excessive Pedal Travel 6 X NO O
Pedal Goes To The Floor 6 X
Stop Light On Without Brakes 3
All Brakes Drag 5
Rear Brakes Drag 2 NO NO
Grabby Brakes O X
Spongy Brake Pedal X NO
Premature Rear Brake Lockup 4 NO NO O
Excessive Pedal Effort 1 O
Rough Engine Idle NO O
Brake Chatter (Rough) NO NO X
Surge During Braking NO NO X
Noise During Braking NO NO X
Rattle Or Clunking Noise NO NO X
Pedal Pulsates During Braking NO NO X
Pull To Right Or Left NO NO X
No: Not A Possible Cause X: Most Likely Cause O: Possible Cause
PLBRAKES 5 - 9

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)