2003 FORD MUSTANG battery

A1 CHECK THE BATTERY POWER SUPPLY TO THE INSTRUMENT
CLUSTER CAUTION: Use the correct probe adapter(s) when making
measurements. Failure to use the correct probe adapter(s) may
damage the connector.
z Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure voltage between the instrument cluster C220b pin 10,
circuit 729 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit.
TEST the system
for normal
operation. A2 CHECK THE RUN POWER SUPPLY TO THE INSTRUMENT
CLUSTER z
Key in ON position.
z Measure the voltage between the instrument cluster C220b pin 11,
circuit 489 (PK/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A3 .
No
REPAIR the circuit.
TEST the system
for normal
operation. A3 CHECK THE RUN/START POWER SUPPLY TO THE INSTRUMENT
CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the instrument cluster C220b pin 12,
circuit 20 (WH/LB), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A4 .
No
REPAIR the circuit.
TEST the system
for normal
operation. Klj . 14 ba
412003 Mustang Workshop Manual
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z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Generic Electronic Module (GEM) PID.
z Monitor the GEM PIDs IGN_KEY, IGN_S, IGN_R, and
IGN_A, while inserting the ignition key and cycling the
ignition switch through all the positions.
z Did the PIDs agree with the ignition switch positions? K2 CHECK IF THE GEM IS RECEIVING THE CORRECT
SAFETY BELT SWITCH STATUS z
Monitor GEM PID D_SBELT while buckling and unbuckling
the driver safety belt.
z Did the PID display IN with the safety belt buckled and
OUT with the safety belt unbuckled? Yes
GO to
K3 .
No
REFER to Section 413 - 09 .
K3 CHECK THE GEM FOR INTERNAL OPEN OR SHORT
z
Key in OFF position.
z Monitor the safety belt warning indicator when turning the
ignition from the OFF to the ON position.
z Key in ON position.
z Did the safety belt warning indicator illuminate for
approximately three seconds and turn off? Yes
GO to
K10 .
No
GO to K4 .
K4 DETERMINE IF SAFETY BELT INDICATOR CIRCUIT IS
SHORTED TO GROUND z
Buckle the driver safety belt.
z Is the safety belt indicator always on? Yes
GO to
K5 .
No
GO to K7 .
K5 CHECK IF THE GEM IS INTERNALLY GROUNDED
z
Key in OFF position.
z Disconnect: GEM C201e.
z Key in ON position.
z Observe the safety belt warning indicator.
z Is the safety belt warning indicator always on? Yes
GO to
K6 .
No
GO to K10 .
K6 CHECK CIRCUIT 450 (DG/LG) FOR A SHORT TO GROUND
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance between the GEM C201e pin 26,
circuit 450 (DG/LG), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
K11 .
No
REPAIR the circuit. TEST
the system for normal
operation. K7 CHECK CIRCUIT 450 (DG/LG) FOR A SHORT TO
BATTERY z
Key in OFF position.
z Disconnect: GEM C201e.
z Disconnect: Instrument Cluster C220a. Yes
REPAIR the circuit. TEST
the system for normal Klj . 24 ba
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z
Is the resistance greater than 10,000 ohms? No
REPAIR the circuit. TEST
the system for normal
operation.
O9 CHECK CIRCUIT 128 (VT/YE) FOR SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201e.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the GEM C201e pin 13, circuit
128 (VT/YE), harness side and ground.
z Is any voltage indicated? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
GO to
O10 .
O10 CHECK CIRCUIT 128 (VT/YE) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between the GEM C201e pin 13,
circuit 128 (VT/YE), harness side and the instrument cluster
C220b pin 14, circuit 128 (VT/YE), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
O15 .
No
REPAIR the circuit. TEST
the system for normal
operation. O11 CHECK THE BRAKE FLUID LEVEL SWITCH FOR AN
INTERNAL GROUND z
Key in OFF position.
z Disconnect: Brake Fluid Level Switch C124.
z Key in ON position.
z With the parking brake released, observe the BRAKE
warning indicator.
z Is the BRAKE warning indicator always on? Yes
GO to
O12 .
No
INSTALL a new brake fluid
level switch. TEST the
system for normal
operation. Klj . 30 ba
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PINPOINT TEST V: THE INSTRUMENT CLUSTER IS INOPERATIVE GO to
U2 .
U2 DETERMINE IF INSTRUMENT
CLUSTER IS AT FAULT z
Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode
on the diagnostic tool: Instrument
Cluster Active Command.
z Trigger the instrument cluster active
command TRAC OFF.
z Did the traction control indicator
illuminate? Yes
REFER to
Section 206 - 09B .
No
GO to U3 .
U3 CHECK FOR CORRECT
INSTRUMENT CLUSTER OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they seat
correctly.
z Operate the system and verify the
concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the
system for normal operation.
No
The system is operating correctly at this time.
Concern may have been caused by a loose or
corroded connector. CLEAR the DTCs. REPEAT
the self- test. Test Step Result / Action to Take
V1 CHECK THE BATTERY POWER SUPPLY TO THE
INSTRUMENT CLUSTER CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure voltage between the instrument cluster C220b pin
10, circuit 729 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
V2 .
No
REPAIR the circuit. TEST
the system for normal
operation. V2 CHECK THE RUN POWER SUPPLY TO THE INSTRUMENT
CLUSTER z
Key in ON position.
z Measure the voltage between the instrument cluster C220b
pin 11, circuit 489 (PK/BK), harness side and ground. Yes
GO to
V3 . Klj . 38 ba
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REMOVAL AND INSTALLATION
Instrument Cluster
Removal and Installation
All vehicles
1. CAUTION: Electronic modules are sensitive to electrical charges. If exposed to
these charges, damage may result.
Disconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
2. Remove the headlamp switch knob. zPull out the headlamp switch knob and insert a thin tool in the slot to release the knob
from the shaft.
3. Remove the screws and remove the instrument cluster finish panel. 4. Remove the screws and pull the instrument cluster forward to expose the electrical connector. SECTION 413-
01: Instrument Cluster 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Horn
Refer to Wiring Diagrams Cell
44 , Horns/Cigar Lighter for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the horn (13832).
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If fault is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 413-
06: Horn 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051
Visual Inspection Chart Mechanical Electrical
z
Damaged horns
z Damaged horn switch
z Damaged air bag sliding contact
(14A664) z
Blown battery junction box (BJB) Fuse Horn
Relay (20A)
z Damaged wiring harness
z Damaged connections
z Damaged horn relay
z Damaged horn switch
Symptom Chart Condition
Possible Sources Action
z The horn does not
sound z
BJB Fuse Horn Relay (20A).
z Circuitry.
z Horn relay.
z Air bag sliding contact.
z Horn switch.
z Horns. z
GO to
Pinpoint Test A .
z The horn sounds
continuously z
Circuitry.
z Horn relay.
z Remote entry system (generic
electronic module [GEM]) z
GO to
Pinpoint Test B . Klj . 1 ba
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PINPOINT TEST B: THE HORN SOUNDS CONTINUOUSLY connector Pin 3, Circuit 6 (component side), and air bag sliding
contact C218a Pin 2, Circuit 6 (component side).
z Is the resistance less than 5 ohms? No
INSTALL a new air
bag sliding contact.
REFER to
Section 501 - 20B . TEST the
system for normal
operation. A7 CHECK THE STEERING WHEEL SWITCH HARNESS
z
Inspect the steering wheel switch harness for chafing, opens or
possible short to ground.
z Is the steering wheel switch harness OK? Yes
INSTALL a new horn
switch. REFER to
Switch
— Horn . TEST
the system for normal
operation.
No
INSTALL a new
steering wheel switch
harness. TEST the
system for normal
operation. Test Step Result / Action to Take
B1 CHECK HORN CIRCUIT 1 (DB)
z
Key in OFF position.
z Disconnect: Horn Relay.
z Does the horn continue to sound? Yes
REPAIR Circuit 1 (DB) for short to battery. TEST
the system for normal operation.
No
GO to
B2 .
B2 CHECK HORN RELAY
z
Check the horn relay; refer to Wiring
Diagrams Cell 149.
z Is the horn relay OK? Yes
REINSTALL the horn relay. GO to
B3 .
No
INSTALL a new horn relay. TEST the system for
normal operation. B3 CHECK CIRCUIT 6 (YE/LG)
z
Disconnect: Air Bag Sliding Contact
C218a .
z Does the horn continue to sound? Yes
GO to
B4 .
No
RECONNECT the air bag sliding contact. GO to
B5 .
B4 CHECK GEM INPUT
z
Disconnect: GEM C201e. Yes Klj . 4 ba
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Pinpoint Tests
CAUTION: Before removing and installing the generic electronic module (GEM) or its
connectors, disconnect the battery. Failure to follow this caution will result in the GEM storing
many erroneous DTCs, and it may exhibit erratic operation after installation.
CAUTION: Be careful when probing the central junction box (CJB), or any connectors.
Damage will result to the connector receptacle if the probe or terminal used is too large.
CAUTION: Electronic modules are sensitive to static discharges. If exposed to these
charges, damage may result.
NOTE: If continuous DTCs are recorded and the symptom is not present when carrying out the
pinpoint tests, an intermittent concern may be the cause. Always check for loose connections and
corroded terminals.
Complete the entire pinpoint test related to the symptom before installing a new GEM.
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE (GEM) Test Step Result / Action to Take
A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a.
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 4 400 (LB/BK)
C201a 1 1006 (DG/WH)
C201b 2 1001 (WH/YE)
C201b 3 193 (YE/LG) Yes
GO to
A2 .
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 4,
circuit 397 (BK/WH), harness side and ground. Yes
GO to
A3 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. Klj . 5 ba
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