2003 FORD MUSTANG brake light

occurs on first
(morning) brake
application
pads.
Caused by humidity and
low disc brake pad
temperature.
z Squealing noise— a
continuous squeal z
Disc brake pads
or linings worn
below minimum
thickness. z
INSTALL new disc brake
pads. REFER to Section 206 - 03 for front disc brake
pads or Section 206 - 04 for
rear disc brake pads.
z Squealing noise— an
intermittent squeal
brought on by cold,
heat, water, mud or
snow z
Disc brake pad. zAcceptable condition.
z Groaning noise—
occurs at low speeds
with brake lightly
applied (creeping) z
Disc brake
pads. z
Acceptable condition.
z Grinding noise—
continuous z
Disc brake pads
or linings worn
below minimum
thickness. z
INSPECT the disc brake
pads, brake discs and
attaching hardware for
damage. REPAIR or
INSTALL new components
as necessary. REFER to
Section 206 - 03 for front
disc brakes and Section 206 - 04 for rear disc brakes.
z Moaning noise zBrake linings
contaminated
with grease or
oil. z
INSPECT the brake pads
and shoes for
contamination. REPAIR or
INSTALL new components
as necessary. REFER to
Section 206 - 03 for front
disc brakes or Section 206 -
04 for rear disc brakes.
z Brake
vibration/shudder—
occurs when brakes
are applied z
Uneven disc or
drum wear.
z Uneven disc
brake pad or
lining transfer.
z Suspension
components. z
Go To Pinpoint Test A .
z Brake
vibration/shudder—
occurs when the brake
pedal is released z
Brake drag. zINSPECT the disc brake
pads or linings for
premature wear. REPAIR
or INSTALL a new caliper
or wheel cylinder as
necessary. REFER to
Section 206 - 03 for front
disc brakes and Section 206 - 04 for rear disc brakes.
Symptom Chart—
Driveline Noise/Vibration Condition
Possible Sources Action
z Axle howling or
whine— front or rear
axle z
Axle lubricant
low. z
CHECK the lubricant level.
FILL the axle to
specification.
z Axle housing zINSPECT the axle housing Klj . 17 ba
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Pinpoint Tests
The pinpoint tests are a step-by-
step diagnostic process designed to determine the cause of a z
Bump—occurs
when shifting
from PARK to
a drive or
reverse
position.
Similar to
Clunk but with
no sound z
Initial gear
engagement. z
Acceptable condition.
z Buzz or hiss zIncorrect driveline
angles. z
CHECK for correct driveline
angles. REPAIR as
necessary. REFER to Section 205 - 00 .
z Worn or damaged
main control
solenoids or valves. z
Using a transmission tester,
ACTIVATE the solenoids to
duplicate sound. INSTALL
new components as
necessary. REFER to Section 307 - 01 .
z Vibration— a
high frequency
(20–80 Hz) that
is felt through
the seat or
gear shifter.
Changes with
engine speed z
Transmission cooler
lines grounded out. z
CHECK the transmission
cooler lines. REPAIR as
necessary.
z Flexplate to torque
converter nuts loose. z
CHECK the flexplate nuts.
TIGHTEN to specification.
REFER to Section 307 - 01 .
z Fluid filler tube
grounded out. z
CHECK the fluid filler tube.
REPAIR as necessary.
z Shift cable incorrectly
routed, grounded out
or loose. z
CHECK the shift cable.
REPAIR as necessary.
Section 307 - 05 .
z Shutter or
chatter—
occurs with
light to medium
acceleration
from low
speeds or a
stop z
Electrical
inputs/outputs.
z Vehicle wiring
harness.
z Incorrect
inputs/outputs from
the powertrain control
module (PCM), digital
transmission range
(TR) sensor, brake
pedal position (BPP)
sensor, throttle
position (TP) sensor,
transmission speed
sensor (TSS), output
speed shaft (OSS)
sensor or the torque
converter clutch
(TCC). z
CARRY OUT a Torque
Converter Clutch Operation
Test. RUN on- board
diagnostics or self- test.
REFER to Section 307 - 01 .
CLEAR the DTC's, ROAD
TEST and RERUN on- board
diagnostics or self- test. Klj . 47 ba
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condition. It may not always be necessary to follow a pinpoint test to its conclusion. Carry out only the
steps necessary to correct the condition. Then, test the system for normal operation. Sometimes, it is
necessary to remove various vehicle components to gain access to the component requiring testing.
Reinstall all components after verifying system operation is normal.
PINPOINT TEST A: BRAKE VIBRATION/SHUDDER
Test Step Result / Action to Take
A1 ROAD TEST THE VEHICLE—
LIGHT BRAKING z
Check that the wheel and tires are correct for the vehicle.
Inspect the tires for abnormal wear patterns.
z Road test the vehicle. Warm the brakes by slowing the vehicle
a few times from 80– 32 km/h (50 to 20 mph) using light braking
applications. At highway speeds of 89–97 km/h (55- 60 mph),
apply the brake using a light pedal force.
z Is there a vibration/shudder felt in the steering wheel, seat
or brake pedal? Yes
GO to
A4 .
No
GO to A2 .
A2 ROAD TEST THE VEHICLE—
MODERATE TO HEAVY
BRAKING z
Road test the vehicle. At highway speeds of 89–97 km/h (55- 60
mph), apply the brake using a moderate to heavy pedal force.
z Is there a vibration/shudder? Yes
For vehicles with ABS,
GO to
A3 . For vehicles
with standard brakes,
GO to A4 .
No
Vehicle is OK. VERIFY
condition with customer.
TEST the vehicle for
normal operation. A3 NORMAL ACTUATION OF THE ABS SYSTEM DIAGNOSIS
z
During moderate to heavy braking, noise from the hydraulic
control unit (HCU) and pulsation in the brake pedal can be
observed. Pedal pulsation coupled with noise during heavy
braking or on loose gravel, bumps, wet or snowy surfaces is
acceptable and indicates correct functioning of the ABS
system. Pedal pulsation or steering wheel nibble, (frequency is
proportioned to the vehicle speed) indicates a concern with a
brake or suspension component.
z Is the vibration/shudder vehicle speed sensitive? Yes
GO to
A5 .
No
The brake system is
operating correctly. A4 APPLICATION OF THE PARKING BRAKE
z
NOTE: Begin at the front of the vehicle unless the vibration or
shudder has been isolated to the rear.
z This test is not applicable to vehicles with drum- in-hat type
parking brakes. For vehicles with drum- in-hat parking brakes,
proceed to the next test. For all other vehicles, apply the
parking brake to identify if the problem is in the front or rear
brake. At highway speeds of 89–97 km/h (55- 60 mph), lightly
apply the parking brake until the vehicle slows down. Release
the parking brake immediately after the test.
z Is there a vibration/shudder? Yes
GO to
A7 .
No
GO to A5 .
A5 CHECK THE FRONT WHEEL BEARINGS
z
Check the front wheel bearings. Refer to Wheel Bearing Check in this section.
z Are the wheel bearings OK? Yes
GO to
A6 . Klj . 48 ba
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6. For vehicles with a two-
piece hub and brake disc assembly:
z Match-mark before disassembly.
z Remove the brake disc.
z Clean the hub and brake disc mounting surfaces with metal surface cleaner.
z Using a die grinder with a mild abrasive (Scotch Brite® type), remove any rust or
corrosion from the hub and brake disc mounting surfaces.
z Align the match- marks and reinstall the brake disc on the hub.
7. CAUTION: Do not use a bench lathe to machine brake discs.
NOTE: The depth of cut must be between 0.10 and 0.20 mm (0.004 and 0.008 inch). Lighter
cuts will cause heat and wear. Heavier cuts will cause poor brake disc surface finish.
Using an on- car brake lathe, machine the brake discs. Follow the manufacturer's instructions.
After machining, make sure the brake disc still meets the thickness specification.
8. Using the special tools, verify that the brake disc lateral runout is now within specification. For additional information, refer to Section 206 - 00 .
9. Remove the special tool hub adapter.
10. Remove any remaining metal chips from the machining operation.
11. For vehicles with a two- piece hub and brake disc assembly:
z Remove the brake disc from the hub.
z Remove any remaining metal chips from hub and brake disc mounting surfaces and from
the ABS sensor.
z Apply a liberal amount of lubricant to the hub flange, pilot area and to the brake disc- to-
hub mounting surface.
z Using the match marks, mount the brake disc on the hub.
12. Install the brake caliper anchor plate and the brake caliper.
13. Install the tire and wheel assembly.
14. Test the system for normal operation. Klj . 2 ba
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Component Tests
Driveline Vibration
An analysis of driveline vibration can also be conducted using the Vibration Analyzer; follow the
manufacturer's directions.
Driveline vibration exhibits a higher frequency and lower amplitude than does high-
speed shake.
Driveline vibration is directly related to the speed of the vehicle and is usually noticed at various speed
ranges. Driveline vibration can be perceived as a tremor in the floorpan or is heard as a rumble, hum,
or boom. Driveline vibration can exist in all drive modes, but may exhibit different symptoms depending
upon whether the vehicle is accelerating, decelerating, floating, or coasting. Check the driveline angles
if the vibration is particularly noticeable during acceleration or deceleration, especially at lower speeds.
Driveline vibration can be duplicated by supporting the axle upon a hoist or upon jack stands, though
the brakes may need to be applied lightly in order to simulate road resistance.
1. Raise the vehicle promptly after road testing. Use a twin- post hoist or jack stands to prevent tire
flat- spotting. Engage the drivetrain and accelerate to the observed road test speed to verify the lubricant type.
205 - 02B . CLEAN and
REFILL the axle to
specification.
z Axle overheating zLubricant level too
low. z
CHECK the lubricant level.
FILL the axle to specification.
z Incorrect or
contaminated
lubricant type. z
INSPECT the axle for
damage. REPAIR as
necessary. CLEAN and
REFILL the axle to
specification.
z Bearing preload
adjusted too tight. z
CHECK the ring and pinion for
damage. INSPECT the ring
and pinion wear pattern.
ADJUST the preload as
necessary.
z Excessive gear
wear. z
INSPECT all the axle gears
for wear or damage. INSTALL
new components as
necessary.
z Incorrect ring gear
backlash. z
INSPECT the ring gear for
scoring. INSPECT the ring
and pinion wear pattern.
ADJUST the ring gear
backlash as necessary.
z Broken gear teeth
on the ring gear
or pinion z
Overloading the
vehicle. z
INSTALL a new ring and
pinion. REFER to Section 205 - 02A or
Section 205 - 02B .
z Axle shaft broken zOverloading the
vehicle. z
INSTALL a new axle shaft.
REFER to Section 205 - 02A or
Section 205 - 02B .
z Misaligned axle
shaft tube. z
INSPECT the axle for
damage. CHECK axle shaft
tube alignment. INSTALL a
new axle shaft. REFER to
Section 205 - 02A or
Section 205 - 02B . Klj . 11 ba
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off the floor.
With the engine off, raise only one rear wheel. Install the special tool on the wheel nuts.
Use a torque wrench with a capacity of at least 271 Nm (200 lb-
ft) to rotate the axle shaft. Be sure that
the transmission is in NEUTRAL, and that one rear wheel is on the floor while the other rear wheel is
raised off the floor. The breakaway torque required to start rotation must be at least 27 Nm (20 lb- ft).
The initial breakaway torque may be higher than the continuous turning torque.
The axle shaft must turn with even pressure throughout the check without slipping or binding. If the
torque reading is less than specified, check the differential case. Refer to Section 205 - 02A or
Section 205 - 02B .
Traction- Lok® Differential Check Road Test
1. Place one wheel on a dry surface and the other wheel on ice, mud or snow.
2. Gradually open the throttle to obtain maximum traction prior to break away. The ability to move the vehicle demonstrates correct operation of a Traction- Lok® rear axle assembly.
3. When starting with one wheel on an excessively slippery surface, a slight application of the parking brake may be necessary to help energize the Traction- Lok® feature of the differential.
Release the brake when traction is established. Use light throttle on starting to provide
maximum traction.
4. If, with unequal traction, both wheels slip, the limited slip rear axle has done all it can possibly do.
5. In extreme cases of differences in traction, the wheel with the least traction may spin after the Traction-Lok® has transferred as much torque as possible to the non- slipping wheel. Klj . 15 ba
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not machine a new brake disc.
7. For vehicles with a two- piece hub and brake disc assembly:
z Match-mark before disassembly.
z Remove the brake disc.
z Using a die grinder with a mild abrasive (Scotch Brite® type), remove any rust or
corrosion from the hub and brake disc mounting surfaces.
z Align the match- marks and reinstall the brake disc on the hub.
8. CAUTION: Do not use a bench lathe to machine brake discs.
NOTE: The depth of cut must be between 0.10 and 0.20 mm (0.004 and 0.008 inch). Lighter
cuts will cause heat and wear. Heavier cuts will cause poor brake disc surface finish.
Using on- vehicle brake lathe, machine the brake discs. Follow the manufacturer's instructions.
After machining, make sure the brake disc still meets the thickness specification.
9. Using a dial indicator, verify that the brake disc lateral runout is now within vehicle specification.
10. Remove any metal chips.
11. Remove the hub adapter.
12. Remove any remaining metal chips from the machining operation.
13. CAUTION: Do not carry out this step on rear drum- in-hat brake discs.
For vehicles with a two- piece hub and a non drum- in-hat brake disc assembly:
z Remove the brake disc from the hub.
z Remove any remaining metal chips from hub and brake disc mounting surfaces and from
the ABS sensor.
z Apply High Temperature Nickel Anti- Seize Lubricant F6AZ-9L494-AA to the mounting
surfaces.
z Using the match- marks, mount the brake disc on the hub.
14. Install the caliper and check brake operation.
Symptom Chart Symptom Chart
Condition
Possible Sources Action
z The Brakes Pull or
Drift z
Tire air pressure.
z Wheel alignment.
z Brake pads.
z Brake components.
z Suspension
component. z
Go To Pinpoint Test A .
z The Red Brake
Warning Indicator Is z
Instrument cluster.
z Circuit. z
Go To Pinpoint Test B . Klj . 4 ba
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Always On
zParking brake.
z Brake fluid level.
z Vibration When
Brakes Are Applied z
Rear disc brakes.
z Front disc brakes. z
REFER to Section 100 -
04 .
z Brake Pedal Goes
Down Fast z
Brake fluid level. zFILL the brake master
cylinder reservoir.
BLEED the system.
z Air in system. zBLEED the system.
z Brake master
cylinder. z
PERFORM the brake
master cylinder
component test in this
section.
z The Brake Pedal
Eases Down Slowly z
Air in system. zBLEED the system.
REFER to Bleeding —
System in this section.
z Brake master
cylinder. z
PERFORM the brake
master cylinder
component test in this
section.
z Brake Lockup During
Light Brake Pedal
Force z
Disc brake
component.
z Parking brake
component.
z Anti- lock brake
control system. z
Go To Pinpoint Test C .
z Excessive/Erratic
Brake Pedal Travel z
Leak in hydraulic
system.
z Air in system.
z Disc brake caliper.
z Brake master
cylinder. z
Go To Pinpoint Test D .
z Brakes Drag zParking brake
component. z
REPAIR or INSTALL new
components as
necessary. REFER to
Section 206 - 05 .
z Disc brake caliper. zREPAIR or INSTALL a
new brake caliper as
necessary. REFER to
Section 206 - 03 and
Section 206 - 04 .
z Brake booster-to-
brake master
cylinder push rod
adjustment. z
ADJUST the push rod.
REFER to Section 206 -
07 .
z Brake master
cylinder. z
PERFORM the brake
master cylinder
component test in this
section.
z Excessive Brake
Pedal Effort z
Power brake
booster. z
PERFORM the brake
booster component test
in this section.
z Power brake
booster check
valve (2365). z
PERFORM the check
valve component test in
this section.
z Power brake
booster hose. z
REROUTE, REPAIR or
INSTALL a new brake Klj . 5 ba
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