2003 FORD MUSTANG key

z
Key in ON position.
z Does the brake warning indicator stay on? cylinder reservoir. TEST the
system for normal operation.
B2 CHECK PARKING BRAKE SWITCH
z
Key in OFF position.
z Disconnect: Parking Brake Switch.
z Key in ON position.
z Does the brake warning light stay on? Yes
GO to
B3 .
No
INSTALL a new parking brake
switch. TEST the system for
normal operation. B3 CHECK THE GEM
z
Key in OFF position.
z Disconnect: GEM C201e.
z Measure resistance to ground at C201e- 13.
z Is the resistance greater than 10,000 ohms? Yes
REPAIR the GEM. TEST the
system for normal operation.
No
For vehicles without Daytime
Running Lights (DRL), GO to
B4
. For vehicles with DRL, GO
to B5 .
B4 CHECK CIRCUITS 977 (VT/WH), 22 (LB/BK) AND 128
(VT/YE) z
Remove the fused jumper from C124.
z Measure the resistance to ground at C124- 2.
z Is the resistance greater than 10,000 ohms? Yes
REPAIR the ground short in
circuit 128 (VT/YE). TEST the
system for normal operation.
No
REPAIR the ground short in
circuit 977 (VT/WH) or circuit 22
(LB/BK). TEST the system for
normal operation.
B5 CHECK CIRCUIT 128 (VT/YE)
z
Remove the fused jumper from C124.
z Measure the resistance to ground at C201e- 13. Yes
GO to
B6 . Klj . 8 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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PINPOINT TEST G: HYDRO-
BOOST BRAKE SYSTEM OPERATION
SUSPECT connections between the power steering pump reservoir and
between the power steering pump reservoir and the hydro-
boost
power brake booster.
z Are there any obstructions? REMOVE
obstructions or
INSTALL a new
hose.
No
GO to
F2 .
F2 CHECK BOOSTER OPERATION
z
Have an assistant check the fluid in the power steering pump
reservoir while rapidly applying the brake pedal approximately one
inch.
z Does the fluid show any movement or spouting? Yes
System OK.
No
INSTALL a new
hydro-boost
assembly. Test Step Result / Action to Take
G1 CHECK BASIC OPERATION
z
Key in OFF position.
z Press and release brake pedal several times to deplete all
hydraulic pressure from the hydro- boost power brake
booster.
z Press and hold brake pedal with light pressure.
z Key in START position.
z Does the brake pedal fall slightly and hold, and is less
pressure now required to hold brake pedal at the new
position? Yes
Hydro-
boost is OK.
No
GO to G2 .
G2 CHECK FOR HYDRAULIC BRAKE LEAK
z
With engine running, press and release brake pedal several
times.
z Hold brake pedal down with medium pressure, 34- 47 Nm
(25- 35 lb- ft).
z Does brake pedal move toward floor? Yes
GO to
G3 .
No
GO to G4 .
G3 CHECK FOR LEAKS —
BRAKE FLUID LINES z
Check for leaks at brake lines, including brake master
cylinder and brake hose.
z Do components check OK? Yes
COMPLETE master cylinder
By-
Pass Condition Test in
this section.
No
INSTALL new hoses and
lines as necessary. G4 CHECK HYDRO-
BOOST CONNECTIONS z
Clean the hydro- boost power brake booster, power steering
pressure hose, power steering gear pressure hose and
power steering return hose and connection.
z Start engine and run at idle.
z Check hose connections for leakage.
z Do hose connections check OK? Yes
GO to
G5 .
No
REPAIR or INSTALL new
hose and connections as
necessary. G5 CHECK FOR HYDRO-
BOOST LEAK Klj . 12 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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8. Remove the following components:
1. spring cover
2. spring
3. washer
4. key plate
5. push rod
6. strut pin
7. push rod O- ring
9. Remove and discard the O- ring seal from the push rod.
10. Remove the parking brake lever (2A637). 1. Remove the parking brake return spring (2456).
2. Remove the limiting bolt (2A795).
3. Remove the parking brake lever.
4. Remove the parking brake lever shaft seal from the caliper bore.
Assembly 1. CAUTION: Do not reuse piston seals or dust boots. Install new seals or dust boots
or damage to the vehicle can occur. Klj . 3 ba
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3. If the concern remains after the inspection, connect the scan tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the scan tool does not communicate with the vehicle: 1. Check that the program card is correctly installed.
2. Check the connections to the vehicle.
3. Check the ignition switch position.
4. If the scan tool still does not communicate with the vehicle, refer to the scan tool Manual.
5. Carry out the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with: 1. CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418-00.
2. NO RESP/NOT EQUIP for the anti- lock brake control module, Go To Pinpoint Test A .
3. SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out self- test diagnostics for the anti-lock brake
control module.
6. If the DTCs retrieved are related to the concern, go to the Anti- Lock Brake Control Module
Diagnostic Trouble Code (DTC) Reference Chart to continue diagnostics.
7. If no DTCs related to the concern are retrieved, GO to Symptom Chart to continue diagnostics.
Anti-Lock Brake Control Module Diagnostic Trouble Code (DTC) Index
NOTE: If a wheel speed signal fault or a pump motor fault is detected, the yellow ABS warning
indicator cannot be reset with the key OFF and key ON method. The vehicle must be driven over 12
km/h (8 mph) for the anti- lock brake control module to carry out a re- check of the system before the
yellow ABS warning indicator is turned OFF. Visual Inspection Chart Mechanical Electrical
z
Low brake fluid
z Anti- lock brake sensor
z Anti- lock brake sensor indicator
z Base brake system z
Central junction box (CJB)Fuse:
„15 (10A)
„ 29 (15A)
„ 33 (15A)
„ 35 (15A)
z Battery junction box (BJB) Fuse:
„ABS 1 (50A)
„ ABS 2 (20A)
z Circuitry
z Damaged or corroded connectors
z Yellow ABS warning indicator
z Loose grounds
Anti-Lock Brake Control Module Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1318 Battery Voltage Low ABS Go To Pinpoint Test C .
B1342 ECU Is Defective ABS INSTALL a new anti-
lock brake control module;
REFER to Module . REPEAT the self-
test. B1484 Brake Pedal Input Open Circuit ABS Go To Pinpoint Test D . Klj . 2 ba
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Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE ANTI-
LOCK
BRAKE CONTROL MODULE warning indicator
system. Test K .
z Base brake
system. z
REFER to
Section 206 -
00 .
z Poor vehicle tracking during
anti- lock function z
Air in the brake
system. z
Go To Pinpoint Test L .
z Hydraulic control
unit (HCU).
z Base brake
system. z
REFER to
Section 206 -
00 .
Test Step Result / Action to
Take A1 CHECK CIRCUIT 601 (LB/PK) FOR AN OPEN
z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Key in ON position.
z Measure the voltage between anti- lock brake control module C135
Pin 8, Circuit 601 (LB/PK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit.
REPEAT the self-
test. A2 CHECK THE ANTI-
LOCK BRAKE CONTROL MODULE GROUNDS z
Measure the resistance between anti- lock brake control module
C135 Pin 12, Circuit 1205 (BK), harness side and ground; and
between anti- lock brake control module C135 Pin 15, Circuit 397
(BK/WH), harness side and ground.
z Are the resistances less than 5 ohms? Yes
INSTALL a new
anti-
lock brake
control module;
REFER to Module .
REPEAT the self-
test.
No
REPAIR the circuit
in question.
REPEAT the self-
test. Klj . 5 ba
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PINPOINT TEST B: UNABLE TO ENTER SELF-
TEST
PINPOINT TEST C: DTC B1318, BATTERY VOLTAGE LOW Test Step Result / Action to Take
B1 CHECK THE COMMUNICATIONS TO THE
ANTI- LOCK BRAKE CONTROL MODULE z
Check the communications to the anti- lock
brake control module.
z Does the scan tool communicate with the
anti-lock brake control module? Yes
INSTALL a new anti-
lock brake control
module; REFER to Module . REPEAT the
self- test.
No
Go To Pinpoint Test A .
Test Step Result / Action to
Take C1 CHECK BATTERY VOLTAGE
z
Measure the battery voltage between the positive and negative
battery posts with the key ON engine OFF (KOEO), and with the
engine running.
z Is the battery voltage between 10 and 13 volts with KOEO, and
between 11 and 17 volts with the engine running? Yes
GO to
C2 .
No
REFER to Section 414 - 00 .
C2 CHECK THE VOLTAGE TO THE ANTI-
LOCK BRAKE CONTROL
MODULE z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Key in ON position.
z Measure the voltage between anti- lock brake control module C135
Pin 8, Circuit 601 (LB/PK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
C3 .
No
REPAIR the circuit.
CLEAR the DTCs.
REPEAT the self-
test. C3 CHECK THE ANTI-
LOCK BRAKE CONTROL MODULE GROUNDS Klj . 6 ba
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