test G FORD MUSTANG 2003 Workshop Manual

PINPOINT TEST I: THE STOPLAMPS ARE ON CONTINUOUSLY z
If the high mounted stoplamp is inoperative, measure the voltage
between the inoperative high mounted stoplamp C475 (C4199 for
Cobra) pin 1, circuit 569 (DG), harness side and ground while
pressing the brake pedal.
z Is the voltage greater than 10 volts? operation.
If rear stoplamp, GO to
H2
.
H2 CHECK CIRCUIT 9 (LG/OG) OR 5 (OG/LB) FOR AN OPEN
z
Disconnect: Multifunction Switch C202b.
z Measure the resistance between the inoperative stoplamp
connector and multifunction switch C202b pin 9, circuit 9
(LG/OG) (LH), or C202b pin 5, circuit 5 (OG/LB) (RH).
z Is the resistance less than 5 ohms? Yes
INSTALL a new
multifunction switch.
REFER to
Section 211 - 05 . TEST the
system for normal
operation.
No
REPAIR the circuit in
question. TEST the
system for normal
operation. Test Step Result / Action to Take
I1 CHECK THE BRAKE PEDAL
POSITION (BPP) SWITCH z
Key in OFF position.
z Disconnect: BPP Switch
C278.
z Do the stoplamps continue
to illuminate? Yes
GO to
I2 .
No
INSTALL a new BPP switch. REFER to Lamp Switch —
Brake Pedal Position (BPP) . TEST the system for normal Klj . 3 ba
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operation.
I2 CHECK THE SPEED
CONTROL SYSTEM z
Disconnect: Speed Control
Servo C122.
z Do the stoplamps continue
to illuminate? Yes
GO to
I3 .
No
REFER to Section 310 - 03 .
I3 CHECK CIRCUIT 511 (LG)
FOR SHORT TO POWER z
Disconnect: Central Junction
Box (CJB) Fuse 35 (15A).
z Do the stoplamps continue
to illuminate? Yes
GO to
I4 .
No
REPAIR the circuit. TEST the system for normal operation. I4 CHECK CIRCUIT 810 (LG/RD)
FOR SHORT TO POWER z
Disconnect: CJB Fuse 41
(15A).
z Do the stoplamps continue
to illuminate? Yes
GO to
I5 .
No
REPAIR the circuit. TEST the system for normal operation. I5 CHECK THE
MULTIFUNCTION SWITCH z
Disconnect: Multifunction
Switch C202b.
z Do the stoplamps continue
to illuminate? Yes
If the high mounted stoplamp is illuminated, REPAIR circuit
569 (DG) or 511 (LG) as necessary. TEST the system for
normal operation.
If only the LH stoplamp is illuminated, REPAIR circuit 9
(LG/OG). TEST the system for normal operation.
If only the RH stoplamp is illuminated, REPAIR circuit 5
(OG/LB). 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
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DIAGNOSIS AND TESTING
Turn Signal and Hazard Lamps
Refer to Wiring Diagrams Cell
90 , Turn/Stop/Hazard Lamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concern.
2. Visually inspect for the following obvious signs of mechanical and electrical damage.
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Multifunction switch z
Central junction box (CJB) Fuse 13 (15A).
z CJB Fuse 18 (15A).
z Circuitry
z Electronic flasher
z Turn signal/hazard lamp
Symptom Chart Condition
Possible Sources Action
z The turn signal
lamps are never
on z
Central junction
box (CJB) fuse 13
(15A).
z CJB Fuse 18
(15A).
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test J . Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST J: THE TURN SIGNAL LAMPS ARE NEVER ON z
Electronic flasher.
z The hazard
flasher lamps are
never on z
Central junction
box (CJB) fuse 13
(15A).
z Circuitry.
z Multifunction
switch.
z Electronic flasher. z
Go To Pinpoint Test K .
z One turn
signal/hazard
lamp is never on z
Turn
signal/hazard
flasher lamp.
z Circuitry. z
REPAIR inoperative turn
signal/hazard flasher lamp
circuit
„LF Circuit 3 (LG/WH).
„ RF Circuit 2 (WH/LB).
„ LR Circuit 9 (LG/OG).
„ RR Circuit 5 (OG/LB).
z The turn signal
lamps are always
on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation.
z The hazard
flasher lamps are
always on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation. Test Step Result / Action to
Take J1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Key in ON position.
z Measure the voltage between the following electronic flasher
C2141 circuits, harness side and ground.
„Pin 2, Circuit 1039 (BK/YE).
„ Pin 3, Circuit 383 (RD/WH).
z Are the voltages greater than 10 volts? Yes
GO to
J2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. J2 CHECK CIRCUIT 44 (LB)
z
Key in OFF position. Yes Klj . 2 ba
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PINPOINT TEST K: THE HAZARD FLASHER LAMPS ARE NEVER ON z
Disconnect: Multifunction Switch C202b.
z Measure the resistance between multifunction switch C202b Pin
44, Circuit 44 (LB), harness side and the electronic flasher C2141
Pin 1, Circuit 44 (LB), harness side; and between multifunction
switch C202b Pin 44, Circuit 44 (LB), 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
J3 .
No
REPAIR the circuit.
TEST the system for
normal operation. J3 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. Test Step Result / Action to
Take K1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Measure the voltage between electronic flasher C2141 Pin 3,
Circuit 383 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
K2 .
No
REPAIR the circuit.
TEST the system for
normal operation. K2 CHECK CIRCUIT 385 (WH/RD)
z
Disconnect: Multifunction Switch C202b. Yes Klj . 3 ba
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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
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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
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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
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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
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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
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