2003 FORD MUSTANG diagram

DIAGNOSIS AND TESTING
Brake System
Refer to Wiring Diagrams Cell
60 , Instrument Cluster for schematic and connector information.
Refer to Wiring Diagrams Cell 97 , Daytime Running Lamps for schematic and connector information.
Inspection and Verification WARNING: Use of any other than the approved DOT 3 brake fluid will cause permanent
damage to brake components and will render the brakes inoperative.
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 spill brake fluid onto painted surfaces. If spilled, wipe up immediately.
NOTE: Always check the fluid level in the brake master cylinder reservoir (2K478) before performing
the test procedures. If the fluid level is not at the correct level, add High Performance DOT 3 Brake
Fluid C6AZ- 19542-AB or equivalent DOT 3 fluid meeting Ford specification ESA- M6C25-A.
NOTE: Prior to performing any diagnosis, make sure the brake warning indicator is functional. For
additional information, refer to Section 413 - 01 .
The first indication that something may be wrong in the brake system is a change in the feeling through
the brake pedal (2455). The brake warning indicator in the instrument cluster and the brake fluid level SECTION 206-
00: Brake System — General Information 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter
105-
R0051 or Equivalent ABS Brake and Pressure Test
Kit
107-
02350 or Equivalent Tire and Wheel Runout Gauge
Set
134-
00199 or Equivalent Klj . 1 ba
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DIAGNOSIS AND TESTING
Anti-
Lock Control
Refer to Wiring Diagrams Cell 42 , Anti-
Lock Brake for schematic and connector information.
Principles of Operation
The anti- lock brake control module receives wheel speed readings from each anti- lock brake sensor
and processes this information to determine if an ABS event is necessary. The anti- lock brake sensor
electrically senses each tooth of the anti- lock brake sensor indicators as it passes through the anti- lock
brake sensor's magnetic field.
The anti- lock brake control module continuously monitors and compares the rotational speed of each
wheel, and when it detects an impending wheel lock, modulates hydraulic brake pressure to the
appropriate brake caliper. This is accomplished by the anti- lock brake control module triggering the
hydraulic control unit (HCU) to open and close the appropriate solenoid valves. Once the affected
wheel returns to normal speed, the anti- lock brake control module returns the solenoid valves to their
normal position, and normal (base) braking resumes.
The anti- lock brake control module is self- monitoring. When the ignition switch is turned to the RUN
position, the anti- lock brake control module will do a preliminary electrical check, and at approximately
12 km/h (8 mph) the pump motor is turned on for approximately one half- second. Any malfunction of
the ABS will cause the ABS to shut off and the yellow ABS warning indicator to illuminate, however,
normal power assisted braking remains.
The ABS control module has the ability to store multiple DTCs in memory.
Inspection and Verification
1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
SECTION 206-
09A: Anti-Lock Control — Rear 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool 73 Digital Multimeter or
equivalent
105-
R0051 Klj . 1 ba
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Anti-Lock Brake Control Module Active Command Index
Symptom Chart ABSRF_I RF ABS Inlet Valve OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG ABSRF_O RF ABS Outlet Valve OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG ABSR_I Rear ABS Inlet Valve OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG ABSR_O Rear ABS Outlet Valve OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG
Anti-Lock Brake Control Module Active
Command Index Active Command Display Action
ABS OUTPUT CONTROL ABS POWER OFF, ON
DSBL TOG OFF, ON
LF INLET OFF, ON
LF OUTLET OFF, ON
RF INLET OFF, ON
RF OUTLET OFF, ON
R INLET OFF, ON
R OUTLET OFF, ON
Symptom Chart
NOTE: Refer to the Wiring Diagrams for connector numbers stated in the Pinpoint
tests. Condition
Possible Sources Action
z No communication with the anti-
lock brake control module z
CJB Fuse 29
(15A).
z Circuitry.
z Anti- lock brake
control module. z
Go To Pinpoint Test A .
z Unable to enter self- test. zAnti- lock brake
control module. z
Go To Pinpoint Test B .
z The yellow ABS warning
indicator does not self- check z
Circuitry.
z Anti- lock brake
control module.
z Instrument cluster. z
Go To Pinpoint Test J .
z Spongy brake pedal with no zAir in the brake zGo To Pinpoint Klj . 4 ba
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DIAGNOSIS AND TESTING
Anti-
Lock Control — Traction Control
Refer to Wiring Diagrams Cell 42 , Anti-
Lock Brake System for schematic and connector information.
Principles of Operation
The anti- lock-brake control module receives wheel speed readings from each anti- lock brake sensor
and processes this information to determine if an ABS event is necessary. The anti- lock brake sensor
electrically senses each tooth of the anti- lock brake sensor indicators as it passes through the anti- lock
brake sensor's magnetic field.
The anti- lock brake control module continuously monitors and compares the rotational speed of each
wheel and, when it detects an impending wheel lock, modulates brake pressure to the appropriate
brake caliper. This is accomplished by triggering the hydraulic control unit (HCU) to open and close the
appropriate solenoid valves. Once the affected wheel returns to normal speed, the anti- lock brake
control module returns the solenoid valves to their normal position, and normal (base) braking
resumes.
The anti- lock brake control module is self- monitoring. When the ignition switch is turned to the RUN
position, the anti- lock brake control module will do a preliminary electrical check, and at approximately
12 km/h (8 mph) the pump motor is turned on for approximately one half- second. Also during all
phases of operation the anti- lock brake control module (after the vehicle is in motion) checks for
correct operation of the anti- lock brake sensors. Any malfunction of the ABS will cause the ABS to shut
off and ABS warning indicator to illuminate; normal power assisted braking, however, remains.
The ABS control module has the ability to store multiple DTCs in memory.
The traction control system controls wheelspin by modulating the engine torque by communicating to
the powertrain control module (PCM) and by applying, then releasing, the appropriate brake to restore
traction when one or both drive wheels lose traction and begin to spin during acceleration.
The traction control system can be disabled by depressing the traction control switch. The traction
control system will reset and return to normal traction assist when the ignition switch is cycled or when
the traction control switch is depressed again. SECTION 206-
09B: Anti-Lock Control — Traction Control 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool 73 Digital Multimeter or
equivalent
105-
R0051 Klj . 1 ba
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Anti-Lock Brake Control Module Active Command Index
Symptom Chart Valve
RF_TC_S RF Traction Control Switching
Valve OFF, ON
LR_TC_S LR Traction Control Switching
Valve OFF, ON
RR_TC_S RR Traction Control Switching
Valve OFF, ON
T/ALVAL Left Traction Control Valve
Output State OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG T/ARVAL Right Traction Control Valve
Output State OFF---, OFFO--, OFF
-B-, OFF--G, OFFO- G, OFF-
BG, OFFOBG, ON---, ONO--, ON -B-, ON--G, ONO-
G, ON- BG, ONOBG
Anti-Lock Brake Control Module Active Command Index Active Command Display Action
ABS OUTPUT CONTROL ABS POWER OFF, ON
DSBL TOG OFF, ON
LF INLET OFF, ON
LF OUTLET OFF, ON
RF INLET OFF, ON
RF OUTLET OFF, ON
LR INLET OFF, ON
LR OUTLET OFF, ON
RR INLET OFF, ON
RR OUTLET OFF, ON
TRACTION CONTROL PRIMARY AND SWITCHING VALVE CONTROL LF TC PRV OFF, ON
LF TC SWV OFF, ON
RF TC PRV OFF, ON
RF TC SWV OFF, ON
LR TC PRV OFF, ON
LR TC SWV OFF, ON
RR TC PRV OFF, ON
RR TC SWV OFF, ON
Symptom Chart
NOTE: Refer to the wiring diagrams for connector numbers stated in the pinpoint Klj . 5 ba
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DIAGNOSIS AND TESTING
Steering Column Switches
Refer to Wiring Diagrams Cell
13 , Power Distribution for schematic and connector information.
Refer to Wiring Diagrams Cell 81 , Interval Wiper/Washer for schematic and connector information.
Refer to Wiring Diagrams Cell 85 , Headlamps for schematic and connector information.
Refer to Wiring Diagrams Cell 90 , Turn/Stop/Hazard Lamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the multifunction or ignition switch.
2. Visually inspect for obvious signs of mechanical and electrical damage.
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:
zcheck that the program card is correctly installed.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool 73 Digital Multimeter
105-
R0051 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Ignition key
z Ignition switch
z Multifunction switch
z Turn signal switch
z Hazard/flasher switch z
Battery junction box (BJB) Fuses:
„(3) IGN (40A)
z Central junction box (CJB) Fuses:
„6 (25A)
„ 39 (5A)
z Damaged wiring harness
z Loose or corroded connections Klj . 1 ba
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Symptom Chart
Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE Circuit Failure
B2488 RF Side Repeater Lamp Output
Circuit Failure GEM REFER to
Section 417 - 01 .
C1189 Brake Fluid Level Sensor Input
Short Circuit to Ground GEM REFER to
Section 413 - 01 .
C1223 Lamp Brake Warning Output
Circuit Failure GEM REFER to
Section 413 - 01 .
C1225 Lamp Brake Warning Output
Circuit Short to Battery GEM REFER to
Section 413 - 01 .
Symptom Chart Condition
Possible Sources Action
z No communication with
the generic electronic
module z
CJB Fuse 39
(5A).
z Circuitry.
z GEM. z
Go To Pinpoint Test A .
z The ignition switch is
inoperative z
BJB Fuse IGN
SW (40A).
z Ignition switch.
z Circuitry. z
Go To Pinpoint Test B .
z No power in ACC zIgnition switch.
z Circuitry. z
Go To Pinpoint Test C .
z No power in RUN zIgnition switch.
z Circuitry. z
Go To Pinpoint Test D .
z No power in START zIgnition switch.
z Circuitry. z
Go To Pinpoint Test E .
z The multifunction
switch/hazard switch
does not operate
correctly z
Multifunction
switch. z
Carry out the multifunction
switch component test.
REFER to Wiring Diagrams,
Cell 149, Component
Testing. Test Step Result / Action to Take
CAUTION: Use the correct probe adapter(s) when making measurements. Filaure to
use the correct probe adapter(s) may damage the connector. A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a. Yes
GO to
A2 . Klj . 4 ba
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PINPOINT TEST B: THE IGNITION SWITCH IS INOPERATIVE z
Disconnect: GEM C201b.
z Key in ON position.
z Using the following table. measure the voltage between the
GEM, harness side and ground.
z Are the voltages greater than 10 volts? Connector Pin Circuit
C201a 2 400 (LB/BK)
C201a 3 1006 (DG/WH)
C201b 1 1001 (WH/YE)
C201b 4 193 (YE/LG) No
REPAIR the circuit(s) in
question. TEST the system
for normal operation.
A2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR
OPEN z
Key in OFF position.
z Measure the resistance between the GEM C201b pin 2,
circuit 397 (BK/WH), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
A3 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between GEM C201b pin 2, circuit 397
(BK/WH), harness side and ground.
z Is any voltage present? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
REFER to
Section 418 - 00 .
Test Step Result / Action to Take
B1 CHECK THE IGNITION SWITCH
z
Carry out the ignition switch component test.
REFER to Wiring Diagrams Cell 149,
Component Testing.
z Is the ignition switch OK ? Yes
INSTALL a new BJB. TEST the system for
normal operation. Klj . 5 ba
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