2003 FORD MUSTANG air bleeding

in the brake master cylinder reservoir are also indicators of system concerns.
If a wheel is locked and the vehicle must be moved, open a bleeder screw at the locked wheel (1007)
to let out enough fluid to relieve the pressure. Close the bleeder screw. This bleeding operation may
release the brakes but will not correct the cause of trouble. If this does not relieve the locked wheel
condition, repair the locked components before proceeding.
Inspect all hoses and connections. All unused vacuum connectors should be capped. Make sure
hoses and their connections are correctly secured and in good condition with no holes, soft or
collapsed areas.
Non-
Pressure Leaks
The only part of the brake system that could have a brake fluid loss that does not appear when the
system is under pressure is the brake master cylinder reservoir area. Brake fluid loss can be caused
by a missing or poorly- fitted brake master cylinder filler cap (2162), a punctured or otherwise damaged
brake master cylinder reservoir, a missing or damaged brake master cylinder filler cap gasket, or by
missing, damaged or poorly- fitted sealing grommets between the brake master cylinder (2140) and the
brake master cylinder reservoir.
The brake master cylinder reservoir grommets are not separately serviceable and must be installed
new as part of a new brake master cylinder reservoir.
Install a new flexible brake hose if it shows signs of softening, cracking or other damage.
When installing a new brake hose, position the hose to avoid contact with other vehicle components.
Road Test
Perform a road test to compare actual vehicle braking performance with the performance standards
expected by the driver. The ability of the test driver to make valid comparisons and detect performance
deficiencies will depend on experience.
The driver should have a thorough knowledge of brake system operation and accepted general
performance guidelines in order to make good comparisons and detect performance problems.
Select a road that is reasonably smooth and level. Gravel or bumpy roads are not suitable because the
surface does not allow the tires to grip the road equally. Avoid crowned roads.
A key factor in evaluating brake concerns is the deceleration rate. This varies from vehicle to vehicle
and with changes in operating conditions. It is evident how well the brakes are working after just a few
applications.
Avoid locking the brakes. Locked brakes are not an indication of braking efficiency.
Visual Inspection Chart Mechanical Electrical
z
Brake master cylinder
z Brake caliper piston
z Brake discs
z Brake pads z
Parking brake switch
z Damaged or corroded wiring harness
z Brake master cylinder fluid level switch Klj . 2 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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PINPOINT TEST D: EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
PINPOINT TEST E: HYDRO-
BOOST, NO POWER ASSIST 4481 kPa (510-
650 psi)? INSTALL a new proportioning valve.
RETEST for normal operation.
Test Step Result / Action to Take
D1 CHECK FOR SPONGY PEDAL
z
Key in ON position.
z Operate the brake pedal and note pedal feel.
z Does the pedal feel spongy? Yes
BLEED the brake system. REFER to
Bleeding —
System in this section.
RETEST for normal operation.
No
GO to D2 .
D2 CHECK THE BRAKE PEDAL
z
Inspect the brake pedal and bracket for
binding, obstruction or damage.
z Is the brake pedal OK? Yes
GO to
D3 .
No
REPAIR or INSTALL a new brake pedal as
necessary. RETEST for normal operation. D3 CHECK THE BRAKE COMPONENTS
z
Inspect the calipers bolts, anchor plate bolts
and anti- rattle springs for binding, damage,
contamination and correct installation.
z Are the bolts and springs OK? Yes
GO to
D4 .
No
REPAIR or INSTALL new components as
necessary. RETEST for normal operation. D4 CHECK THE BOOSTER AND MASTER
CYLINDER z
Check the power brake booster and brake
master cylinder for correct installation and
correct push rod adjustment. Refer to
Section 206 - 06 and to Section 206 - 07 .
z Are the power brake booster and the
brake master cylinder OK? Yes
INSPECT the front wheel bearings for
wear, damage and correct installation and
the rear axle end play. CORRECT as
necessary. RETEST for normal operation.
No
CORRECT as necessary. RETEST for
normal operation.
Test Step Result / Action to Take
E1 CHECK FLUID LEVEL IN POWER STEERING
PUMP z
Check fluid level in power steering pump.
z Is level within specification? Yes
GO to
E2 .
No
CHECK for leakage of power steering
fluid. ADD fluid as necessary. E2 CHECK ACCESSORY DRIVE BELT Klj . 10 ba
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Component Tests
Brake Booster
1. Check the hydraulic brake system for leaks or insufficient fluid.
2. With the transmission (7003) in NEUTRAL, stop the engine (6007) and apply the parking brake control (2780). Apply the brake pedal several times to exhaust all vacuum in the system.
3. Apply the brake pedal and hold it in the applied position. Start the engine. If the vacuum system is operating, the brake pedal will tend to move downward under constant foot pressure. If no
motion is felt, the power brake booster system is not functioning. Continue with the following
steps.
4. Remove the vacuum booster hose from the check valve connection. Manifold vacuum must be available at the check valve end of the vacuum booster hose with the engine at idle speed and
the transmission in NEUTRAL. If the manifold vacuum is available to the power brake booster,
connect the vacuum booster hose to the power brake booster check valve and repeat Steps 2
and 3.
5. If no downward movement of the brake pedal is felt, install a new power brake booster.
6. Operate the engine a minimum of 10 seconds at fast idle. Stop the engine, and let the vehicle stand for 10 minutes. Then apply the brake pedal with approximately 89 N (20 lb) of force. The
brake pedal feel should be the same as that noted with the engine operating. If the brake pedal
feels hard (no power assist), install a new power brake booster check valve and retest. If the
brake pedal feels spongy, bleed the hydraulic system to remove air. For additional information,
refer to Bleeding — System in this section. Check Valve z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Apply brake pedal with approximately 444 Nm (100 lb)
force and hold.
z Check hydro-boost unit input seal, housing seal,
accumulator seal, piston seal and spool plug seal for
leakage.
z Is hydro- boost unit free of leaks? Yes
GO to
G6 .
No
INSTALL a new hydro- boost
unit. G6 CHECK RESERVE RETENTION
z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Charge system to pressure by holding the steering wheel at
stop or by pressing the brake pedal with approximately 444
Nm (100 lb) force.
z Key in OFF position.
z Wait five seconds.
z Press brake pedal and observe if there is any power brake
reserve.
z Is there any power brake reserve? Yes
Hydro-
boost unit is OK.
No
INSTALL a new hydro- boost
unit. Klj . 13 ba
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GENERAL PROCEDURES
Bleeding —
Components
Master Cylinder Priming — In-Vehicle or Bench
WARNING: Brake fluid contains polyglycol ethers and polyglycols. Avoid contact with
eyes. Wash hands thoroughly after handling. If brake fluid contacts eyes, flush eyes with
running water for 15 minutes. Get medical attention if irritation persists. If taken internally,
drink water and induce vomiting. Get medical attention immediately.
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding
operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never
reuse the brake fluid that has been drained from the hydraulic system.
CAUTION: Brake fluid is harmful to painted and plastic surfaces. If brake fluid is spilled
onto a painted or plastic surface, immediately wash it with water.
NOTE: When any part of the hydraulic system has been disconnected for repair or installation of new
components, air can enter the system and cause spongy brake pedal (2455) action. This requires
bleeding of the hydraulic system after it has been correctly connected. The hydraulic system can be
bled manually or with pressure bleeding equipment.
NOTE: When a new brake master cylinder (2140) has been installed or the system has been emptied,
or partially emptied, it should be primed to prevent air from entering the system.
1. For in- vehicle priming, disconnect the brake lines.
SECTION 206-
00: Brake System — General Information 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool NGS Flash Cable
418-
F120 (007- 00531) or
Equivalent Klj . 1 ba
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7. Bleed each brake tube at the brake master cylinder as follows:
1. Have an assistant pump the brake pedal, and then hold firm pressure on the brake pedal.
2. Loosen the rear most brake tube fittings until a stream of brake fluid comes out. While the assistant maintains pressure on the brake pedal, tighten the brake tube fitting.
3. Repeat this operation until clear, bubble- free fluid comes out.
4. Refill the brake master cylinder reservoir as necessary. Repeat the bleeding operation at the front brake tube.
Master Cylinder Priming — 4.6L
1. CAUTION: Use only bleed screws on the engine side of the brake master cylinder
(2140). The hydro- boost bleed screw, located near the dash on the hydro- booster
casting, is for the booster cavity filled with power steering fluid, not brake fluid.
Connect a clear waste line to the bleed screw closet to the booster first and the other end in a
container partially filled with recommended brake fluid.
2. Open the bleeder screw, have an assistant push the brake pedal down slowly through full travel, close the bleeder screw, then return brake pedal slowly to full released position. Wait five
seconds, then repeat operation until air bubbles cease to appear.
3. Repeat Step 2 for bleeder screw farthest from hydro- booster. Klj . 3 ba
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GENERAL PROCEDURES
Bleeding —
System
Manual
WARNING: Brake fluid contains polyglycol ethers and polyglycols. Avoid contact with
eyes. Wash hands thoroughly after handling. If brake fluid contacts eyes, flush eyes with
running water for 15 minutes. Get medical attention if irritation persists. If taken internally,
drink water and induce vomiting. Get medical attention immediately.
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding
operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never
reuse the brake fluid that has been drained from the hydraulic system.
CAUTION: Brake fluid is harmful to painted and plastic surfaces. If brake fluid is spilled
onto a painted or plastic surface, immediately wash it with water.
NOTE: When any part of the hydraulic system has been disconnected for repair or installation of new
components, air can get into the system and cause spongy brake pedal action. This requires bleeding
of the hydraulic system after it has been correctly connected. The hydraulic system can be bled
manually or with pressure bleeding equipment.
1. Clean all dirt from and remove the brake master cylinder filler cap and fill the brake master cylinder reservoir with the specified brake fluid.
2. Place a box end wrench on the RH rear bleeder screw. Attach a rubber drain tube to the RH rear bleeder screw and submerge the free end of the tube in a container partially filled with
clean brake fluid.
SECTION 206-
00: Brake System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
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GENERAL PROCEDURES
Hydro-
Boost Bleeding
1. NOTE: The Hydro- Boost power brake booster (2B560) is generally self- bleeding, and the
following procedure will normally bleed the air from the power brake booster. Normal operation
of the vehicle will further remove any additional trapped air.
Fill the power steering oil reservoir (3A697) with MERCON® Multi- Purpose ATF XT-2-QDX or
MERCON® equivalent.
2. Remove the powertrain control module (PCM) fuse to prevent the engine from starting.
3. Crank the engine for several seconds.
4. Check the fluid level in the power steering oil reservoir and add if necessary. Install the powertrain control module (PCM) fuse.
5. Start the engine.
6. With the engine running, turn the steering wheel (3600) from stop- to-stop twice. Turn the engine
off.
7. Depress the brake pedal (2455) several times to discharge the accumulator.
8. Repeat Steps 5 and 6.
9. If foaming occurs, stop the engine and allow the foam to dissipate.
10. Repeat Steps 5 and 6 as required, until all the air is removed from the system (when the foaming stops).
SECTION 206-
07: Power Brake Actuation 2003 Mustang Workshop Manual Klj . 1 ba
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