2003 FORD MUSTANG pinpoint

PINPOINT TEST W: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE (GEM) z
Is the resistance less than 5 ohms? V6 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
CAUTION: Use the correct probe adapter(s) when making measurements. Failure to
use the correct probe adapter(s) may damage the connector. W1 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/BKK)
C201a 1 1006 (DG/WH)
C201b 2 1001 (WH/YE)
C201b 3 193 (YE/LG) Yes
GO to
W2 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. W2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR Klj . 40 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 Tests
PINPOINT TEST A: THE HORN DOES NOT SOUND module.
z Horn switch. Test Step Result / Action to
Take A1 CHECK POWER SUPPLY TO HORN RELAY
z
Disconnect: Horn Relay.
z Measure the voltage between the horn relay connector Pin 2,
Circuit 460 (YE/LB), harness side and ground; and between the
horn relay connector Pin 5, Circuit 460 (YE/LB), harness side and
ground.
z Are the voltages greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. A2 CHECK HORN RELAY
z
Check the horn relay; refer to Wiring Diagrams Cell 149.
z Is the horn relay OK? Yes
GO to
A3 .
No
INSTALL a new horn
relay. TEST the
system for normal
operation. A3 CHECK HORN SWITCH SIGNAL TO HORN RELAY
z
Measure the resistance between horn relay connector Pin 1,
Circuit 6 (YE/LG), harness side and ground under the following
conditions:
Horn Switch Position Horn Switch Position Resistance
Pressed Less than 5 ohms
Released Greater than 10,000 ohms Yes
GO to
A4 .
No
GO to A5 . Klj . 2 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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4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
6. Carry out the Data Link Diagnostic Test. If the diagnostic tool responds with: zCKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for GEM, go to Pinpoint Test A.
z NO RESP/NOT EQUIP for RCM, refer to Section 501 - 20B .
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out self- test diagnostics for the GEM.
7. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
9. If the DTCs retrieved are for the RCM, refer to Section 501 - 20B .
Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
Central junction box (CJB) fuses:
„28 (15A)
„ 32 (15A)
„ 39 (5A)
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1340 Chime Input Request
Circuit Short to Ground GEM Go To Pinpoint Test C .
B1342 ECU Is Defective GEM CLEAR the DTCs. TEST the system for normal operation.
RETRIEVE the DTCs. If DTC B1342 is retrieved, INSTALL
a new GEM. REFER to
Section 419 - 10 .
B1353 Ignition Key-
In Circuit
Open GEM Go To Pinpoint Test B .
B1462 Safety Belt Switch
Circuit Failure GEM Go To Pinpoint Test F . Klj . 3 ba
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Symptom Chart
Symptom Chart Condition
Possible Sources Action
z No communication with the
generic electronic module
(GEM) z
Central junction box
(CJB) fuses:
„39 (5A).
„ 32 (15A).
z Circuitry.
z Generic electronic
module (GEM). z
Go To Pinpoint Test
A .
z The key- in-ignition chime does
not operate correctly z
Central junction box
(CJB) fuses:
„28 (15A).
„ 32 (15A).
z Central junction box
(CJB).
z Driver door ajar
switch.
z Key- in ignition
switch.
z Circuitry.
z Generic electronic
module (GEM).
z Ignition switch. z
Go To Pinpoint Test
B .
z A chime does not operate
correctly— air bag z
Restraint control
module (RCM).
z Circuitry.
z Generic electronic
module (GEM).
z Ignition switch. z
Go To Pinpoint Test
C .
z The door ajar chime does not
operate correctly z
Driver door ajar
switch.
z Passenger door ajar
switch.
z Circuitry.
z Generic electronic
module (GEM).
z Ignition switch. z
Go To Pinpoint Test
D .
z The headlamp on reminder
chime does not operate
correctly z
Headlamp switch .
z Circuitry.
z Generic electronic
module (GEM).
z Driver door ajar
switch.
z Ignition switch. z
Go To Pinpoint Test
E .
z The safety belt warning chime
does not operate correctly z
Circuitry.
z Safety belt switch.
z Generic electronic
module (GEM).
z Ignition switch. z
Go To Pinpoint Test
F .
z The belt minder feature does
not operate correctly z
Circuitry.
z Safety belt switch.
z Generic electronic
module (GEM).
z Ignition switch. z
Go To Pinpoint Test
F . 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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PINPOINT TEST B: THE KEY-
IN-IGNITION CHIME DOES NOT
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between the GEM C201b pin 4, 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 IGNITION STATES
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and IGN_R
while cycling the ignition switch through the OFF, ACC, RUN,
START and key out positions.
z Do the PID values agree with the ignition switch states? Yes
GO to
B2 .
No
GO to B4 .
B2 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM Active Command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
B3 .
No
GO to B11 .
B3 CHECK GEM INPUT FROM DOOR AJAR CIRCUIT
z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW, while opening and closing
the driver door.
z Do the GEM PID D_DR_SW values indicate CLOSED and
AJAR correctly? Yes
GO to
B11 .
No
Go To Pinpoint Test D .
B4 CHECK GEM INPUT VOLTAGE FROM IGNITION SWITCH AT Klj . 6 ba
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