ignition FORD MUSTANG 2003 Owner's Guide

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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PINPOINT TEST C: NO POWER IN ACC
PINPOINT TEST D: NO POWER IN RUN
PINPOINT TEST E: NO POWER IN START No
INSTALL a new ignition switch. REFER to
Ignition Switch
. TEST the system for
normal operation. Test Step Result / Action to Take
C1 CHECK THE RADIO FOR NORMAL OPERATION
z
Key in ON position.
z Check the radio for normal operation.
z Does the radio operate correctly? Yes
GO to
C2 .
No
Go To Pinpoint Test D .
C2 CHECK THE VOLTAGE AT THE IGNITION SWITCH
z
Disconnect: Ignition Switch C250 .
z Measure the voltage between ignition switch C250 Pin B5,
Circuit 1050 (LG/VT), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new ignition
switch. REFER to
Ignition Switch . TEST the system for
normal operation.
No
REPAIR the circuit. TEST the
system for normal operation. Test Step Result / Action to Take
D1 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.
No
INSTALL a new ignition switch. REFER to
Ignition Switch
. TEST the system for
normal operation. Test Step Result / Action to Take
E1 CHECK THE VOLTAGE TO THE IGNITION SWITCH
z
Key in OFF position.
z Disconnect: Ignition Switch C250 . Yes
GO to
E2 . Klj . 6 ba
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Component Test
Ignition Switch Continuity Check
Refer to Wiring Diagrams Cell 149, Component Testing.
Multifunction Switch
Refer to Wiring Diagrams Cell 149, Component Testing. z
Measure the voltage between ignition switch C250 Pin B4,
Circuit 1050 (LG/VT), harness side and ground; and between
ignition switch C250 Pin B5, Circuit 1050 (LG/VT), harness side
and ground.
z Are the voltages greater than 10 volts? No
REPAIR the circuit in
question.TEST system
for normal operation.
E2 CHECK THE CONTINUITY OF THE IGNITION SWITCH
z
Carry out the ignition switch continuity test. REFER to Wiring
Diagrams, Cell 149, Component Testing.
z Does the ignition switch test OK? Yes
GO to
E3 .
No
INSTALL a new ignition
switch. REFER to
Ignition Switch . TEST
the system for normal
operation. E3 CHECK CIRCUIT 16 (RD/LB), AND CIRCUIT 33 (WH/PK)
z
Connect: Ignition Switch C250.
z Turn ignition switch to START.
z Does the starter engage? Yes
REPAIR Circuit 16
(RD/LB). TEST the
system for normal
operation.
No
REPAIR Circuit 33
(WH/PK). TEST the
system for normal
operation. Klj . 7 ba
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REMOVAL AND INSTALLATION
Multifunction Switch
Removal
1. Disconnect the battery ground cable.
2. Remove the ignition switch lock cylinder. 1. Insert the ignition key into the ignition switch lock cylinder and turn to RUN position.
2. Push the ignition switch lock cylinder release tab with a punch while pulling out the ignition switch lock cylinder.
3. Remove the tilt wheel handle.
4. Remove the upper and lower steering column shrouds. 1. Remove the screws.
2. Remove the upper and lower steering column shrouds.
5. Remove the multifunction switch. 1. Remove the screws.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Ignition Switch
Removal
1. Disconnect the battery ground cable.
2. Remove the lower instrument panel steering column cover. 1. Remove the screws.
2. Remove the lower instrument panel steering column cover.
3. Remove the instrument panel reinforcement. 1. Remove the screws.
2. Remove the instrument panel reinforcement.
4. Disconnect the ignition switch electrical connector. 1. Loosen the bolt.
2. Disconnect the ignition switch electrical connector.
5. NOTE: Ignition switch should be in the OFF position.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Klj . 1 ba
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Remove the ignition switch.
1. Remove the screws.
2. Remove the ignition switch.
Installation 1. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms
may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven
16 km (10 mi) or more to relearn the strategy.
To install, reverse the removal procedure. Klj . 2 ba
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REMOVAL AND INSTALLATION
Key Release Button
Removal
1. Disconnect the battery ground cable.
2. Remove the ignition switch lock cylinder. 1. Insert the ignition key into the ignition switch lock cylinder and turn to RUN position.
2. Push the ignition switch lock cylinder release tab with a punch while pulling out the ignition switch lock cylinder.
3. Remove the tilt wheel handle.
4. Remove the upper and lower steering column shrouds. 1. Remove the screws.
2. Remove the upper and lower steering column shrouds.
5. Remove the key release button. 1. Remove the key release button bolt.
SECTION 211-
05: Steering Column Switches 2003 Mustang Workshop Manual Klj . 1 ba
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DESCRIPTION AND OPERATION
Engine
NOTE:
This section contains information, steps and procedures that may not be specific to your
engine.
This section covers general procedures and diagnosis and testing of the engine system, except for
exhaust emission control devices, which are covered in the Powertrain Control/Emissions Diagnosis
Manual.
The engine incorporates the following features:
za closed positive crankcase ventilation (PCV) system. For additional information, refer to
Section 303 - 08 .
z an exhaust emission control system. For additional information, refer to Section 303 - 08 .
z an evaporative emission control system. For additional information, refer to Section 303 - 13 .
Some engines incorporate a fail- safe cooling system. Refer to the appropriate section in Group 303 for
the procedure.
The engine, fuel system, ignition system, emissions system and exhaust system all affect exhaust
emission levels and must be maintained according to the maintenance schedule. Refer to the
scheduled Maintenance Guide.
Correct engine identification is required to order parts. Refer to the appropriate section in Group 303 for the procedure.
For complete vehicle and engine identification codes, refer to
Section 100 - 01 .
SECTION 303-
00: Engine System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
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Inspection and Verification
1. Verify the customer concern by operating the engine to duplicate the condition.
2. Visually inspect for obvious signs of mechanical damage. Refer to the following chart.
3. If the inspection reveals obvious concerns that can be readily identified, repair as necessary.
4. If the concerns remain after the inspection, determine the symptoms. GO to Symptom Chart .
Symptom Chart Material
Item Specification
Gasoline Engine Oil
Dye
164-
R3705 or
equivalent ESE-
M99C103- B1 Engine Oil Refer to owner
literature
Visual Inspection Chart Mechanical
z
Engine coolant leaks
z Engine oil leaks
z Fuel leaks
z Damaged or severely worn parts
z Loose mounting bolts, studs and nuts
Symptom Chart Condition
Possible Sources Action
z Difficult
starting z
Damaged ignition
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Damaged fuel
system. z
Refer to the appropriate section
in Group 303 for the procedure.
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
z Damaged starting
system. z
Refer to the appropriate section
in Group 303 for the procedure. Klj . 2 ba
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