FORD MUSTANG 2003 Workshop Manual

z
Measure the resistance between multifunction switch C202b Pin
385, Circuit 385 (WH/RD), harness side and electronic flasher
C2141 Pin 4, Circuit 385 (WH/RD), harness side; and between
multifunction switch C202b Pin 385, Circuit 385 (WH/RD), harness
side and ground.
z Is the resistance less than 5 ohms between the multifunction
switch and the electronic flasher, and greater than 10,000
ohms between the multifunction switch and ground? GO to
K3 .
No
REPAIR the circuit.
TEST the system for
normal operation. K3 CHECK THE CONTINUITY OF THE MULTIFUNCTION SWITCH
z
Carry out the multifunction switch component test.
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
z Is the switch OK? Yes
INSTALL a new
electronic flasher.
TEST the system for
normal operation.
No
INSTALL a new
multifunction switch;
REFER to
Section 211 - 05 . TEST the
system for normal
operation. Klj . 4 ba
42003 Mustang Workshop Manual
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DIAGNOSIS AND TESTING
Parking, Rear and License Lamps
Refer to Wiring Diagrams Cell
92 , Exterior for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the parking lamps.
2. Visually inspect for the following obvious signs of mechanical and electrical damage.
3. If the concern is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged multifunction switch
(13K359)
z Damaged headlamp switch (11654) z
Blown battery junction box (BJB) Fuse 2
(30A)
z Damaged wiring harness
z Loose or corroded connections
z Damaged parking, rear or license lamp
Symptom Chart Condition
Possible Sources Action
z The parking, rear or license
lamps are inoperative z
BJB Fuse 2 (30A).
z Circuitry.
z Headlamp switch. z
GO to Pinpoint Test L .
z One or more parking, rear or
license bulbs(s) is inoperative z
Parking, rear or
license bulb(s).
z Circuitry. z
GO to Pinpoint Test M .
z The parking, rear or license
lamps are on continuously z
Headlamp switch.
z Circuitry. z
GO to Pinpoint Test N . Klj . 1 ba
32003 Mustang Workshop Manual
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Pinpoint Tests
PINPOINT TEST L: THE PARKING, REAR OR LICENSE LAMPS ARE
INOPERATIVE
PINPOINT TEST M: ONE OR MORE PARKING, REAR OR LICENSE
LAMP(S) IS INOPERATIVE
Test Step Result / Action to Take
L1 CHECK THE VOLTAGE TO THE HEADLAMP SWITCH
z
Disconnect: Headlamp Switch C205.
z Measure the voltage between headlamp switch C205 Pin
B2, Circuit 195 (TN/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
L2 .
No
REPAIR the circuit. TEST the
system for normal operation. L2 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Measure the resistance between headlamp switch C205
Pin R, Circuit 14 (BN), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new headlamp
switch; REFER to
Lamp Switch — Headlamp . TEST the
system for normal operation.
No
REPAIR the circuit. TEST the
system for normal operation. Test Step Result / Action to Take
M1 CHECK THE VOLTAGE TO THE INOPERATIVE
LAMP(S) z
Key in OFF position.
z Disconnect: Inoperative Lamp.
z Place the headlamp switch in the parking lamps
ON position.
z Measure the voltage between inoperative lamp
connector Circuit 14 (BN), harness side and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 1205 (BK) for an open.
TEST the system for normal operation.
No
REPAIR the circuit. TEST the system
for normal operation. Klj . 2 ba
32003 Mustang Workshop Manual
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PINPOINT TEST N: THE PARKING, REAR OR LICENSE LAMPS ARE
ON CONTINUOUSLY
Test Step Result / Action to Take
N1 CHECK THE HEADLAMP
SWITCH z
Key in OFF position.
z Disconnect: Headlamp
Switch C205.
z Key in ON position.
z Are the parking, rear or
licences lamps on? Yes
REPAIR Circuit 14 (BN) for a short to battery. TEST the
system for normal operation.
No
INSTALL a new headlamp switch; REFER to
Lamp Switch — Headlamp . TEST the system for normal operation. Klj . 3 ba
32003 Mustang Workshop Manual
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DIAGNOSIS AND TESTING
Fog Lamps
Refer to Wiring Diagrams Cell
86 , Fog Lamps for schematic and connector information.
Principles of Operation
The fog lamps will only illuminate when the low beam or parking lamps are illuminated. Voltage from
the parking lamp circuit is used to activate the fog lamp relay when the fog lamp switch is ON. Voltage
from the high beam headlamp circuit will activate the fog lamp interrupt relay. When the fog lamp
interrupt relay is active, the ground path is removed from the fog lamp relay, turning off the fog lamps.
Inspection and Verification 1. Verify the customer concern by operating the fog lamps.
2. Visually inspect for the following obvious signs of mechanical and electrical damage.
3. If the concern is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged headlamp switch (11654)
z Damaged fog lamp switch
z Damaged multifunction switch
(13K359) z
Blown battery junction box (BJB) Fuse 27
(20A)
z Blown central junction box (CJB) Fuse 38
(20A)
z Damaged wiring harness
z Loose or corroded connections
z Damaged fog lamp relay
z Damaged fog lamp interrupt relay
z Damaged fog lamp
Symptom Chart Klj . 1 ba
62003 Mustang Workshop Manual
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Pinpoint Tests
PINPOINT TEST O: THE FOG LAMPS ARE INOPERATIVE Condition
Possible Sources Action
z The fog lamps are
inoperative z
BJB Fuse 27 (20A).
z CJB Fuse 38 (20A).
z Circuitry.
z Fog lamp relay.
z Fog lamp interrupt
relay.
z Headlamp switch.
z Fog lamp switch.
z Multifunction switch. z
GO to Pinpoint Test O .
z The individual fog lamp is
inoperative z
Fog lamp bulb.
z Circuitry. z
GO to Pinpoint Test P .
z The fog lamps are on
continuously z
Fog lamp relay.
z Circuitry.
z Fog lamp switch. z
GO to Pinpoint Test Q .
Test Step Result / Action
to Take O1 CHECK THE PARK LAMPS
z
Place the headlamp switch in the PARK position.
z Place the multifunction switch in low beam position.
z Do the park lamps illuminate? Yes
Turn off the
headlamp switch.
GO to
O2 .
No
GO to Pinpoint Test L .
O2 CHECK THE FOG LAMP RELAYS
z
Disconnect: Fog Lamp Relay.
z Disconnect: Fog Lamp Interrupt Relay.
z Check the fog lamp relay and fog lamp interrupt relay; refer to Wiring
Diagrams Cell 149.
z Are the relays OK? Yes
GO to
O3 .
No
INSTALL new
relay(s). TEST
the system for
normal
operation. O3 CHECK THE CIRCUIT 12 (LG/BK)
z
Measure the voltage between fog lamp interrupt relay connector Pin 1,
Circuit 12 (LG/BK), harness side and ground. Yes
GO to
O4 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 2 ba
62003 Mustang Workshop Manual
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z
Is the voltage greater than 0 volts? O4 CHECK CIRCUIT 275 (YE)
z
Measure the resistance between fog lamp interrupt relay connector Pin
4, Circuit 275 (YE), harness side and fog lamp relay connector Pin 85,
Circuit 275 (YE), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
O5 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O5 CHECK CIRCUIT 477 (LB/BK) FOR OPEN
z
Measure the voltage between fog lamp relay connector Pin 30, Circuit
477 (LB/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
O6 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O6 CHECK CIRCUIT 188 (WH/BK)
z
Disconnect: Fog Lamp Switch C240.
z Measure the resistance between fog lamp switch C240 Pin 1, Circuit
188 (WH/BK), harness side and fog lamp relay connector Pin 86,
Circuit 188 (WH/BK), harness side; and between fog lamp switch C240
Pin 1, Circuit 188 (WH/BK), harness side and ground. Yes
GO to
O7 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 3 ba
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PINPOINT TEST P: THE INDIVIDUAL FOG LAMP IS INOPERATIVE z
Is the resistance less than 5 ohms? O7 CHECK CIRCUIT 1205 (BK)
z
Measure the resistance between fog lamp interrupt relay connector Pin
2, Circuit 1205 (BK), and ground.
z Is the resistance less than 5 ohms? Yes
GO to
O8 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O8 CHECK THE FOG LAMP SWITCH
z
Measure the resistance between fog lamp switch C240 Pin 1, Circuit
188 (WH/BK), connector side and fog lamp switch C240 Pin 2, Circuit
14 (BN), connector side with the fog lamp switch on.
z Is the resistance less then 5 ohms? Yes
REPAIR Circuit
478 (TN/OG).
TEST the system
for normal
operation.
No
INSTALL a new
fog lamp switch.
TEST the system
for normal
operation.
Test Step Result / Action to
Take P1 CHECK THE GROUND TO THE FOG LAMP
z
Key in OFF position.
z Disconnect: Inoperative Fog Lamp.
z Measure the resistance between inoperative fog lamp C162 Pin
1 (RH) or C152 Pin 1 (LH), Circuit 1205 (BK), harness side and
ground. Yes
REPAIR Circuit 478
(TN/OG) for open.
TEST the system for
normal operation. Klj . 4 ba
62003 Mustang Workshop Manual
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PINPOINT TEST Q: THE FOG LAMPS ARE ON CONTINUOUSLY z
Is the resistance less than 5 ohms? No
REPAIR Circuit 1205
(BK). TEST the system
for normal operation.
Test Step Result / Action to Take
Q1 CHECK THE FOG LAMP RELAY
z
Disconnect: Fog Lamp Relay.
z Are the fog lamps off? Yes
GO to
Q2 .
No
REPAIR Circuit 478 (TN/OG). TEST the system
for normal operation. Q2 CHECK FOG LAMP RELAY
z
Check the fog lamp relay; refer to
Wiring Diagrams Cell 149.
z Is the fog lamp relay OK? Yes
RECONNECT the fog lamp relay. GO to
Q3 .
No
INSTALL a new fog lamp relay. TEST the system
for normal operation. Q3 CHECK FOG LAMP SWITCH
z
Disconnect: Fog Lamp Switch C240.
z Are the fog lamps off? Yes
INSTALL a new fog lamp switch. TEST the
system for normal operation.
No
REPAIR Circuit 188 (WH/BK) for short. TEST the
system for normal operation. Klj . 5 ba
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Klj . 6 ba
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