Test G FORD MUSTANG 2003 Workshop Manual

z
Does the horn continue to sound? REPAIR Circuit 6 (YE/LG). TEST the system for
normal operation.
No
INSTALL a new GEM; REFER to
Section 419 - 10 .
TEST the system for normal operation. B5 CHECK THE AIR BAG SLIDING
CONTACT z
Deactivate the air bag system. Refer
to Section 501 - 20B .
z Disconnect the steering wheel switch
harness from the air bag sliding
contact.
z Does the horn continue to sound? Yes
INSTALL a new air bag sliding contact. REFER to
Section 501
- 20B . TEST the system for normal
operation.
No
GO to B6 .
B6 CHECK STEERING WHEEL SWITCH
HARNESS z
Inspect the steering wheel switch
harness for shorts, opens, or any
damage.
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. Klj . 5 ba
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DIAGNOSIS AND TESTING
Gauges And Warning Devices
Refer to Wiring Diagrams Cell
59 , Generic Electronic Module for schematic and connector
information.
Refer to Wiring Diagrams Cell 60 , Instrument Cluster for schematic and connector information.
Refer to Wiring Diagrams Cell 66 , Warning Chime for schematic and connector information.
Principles of Operation
Key- In-Ignition Warning Chime
The key- in-ignition warning chime activates when the generic electronic module (GEM) detects the
ignition switch circuits are in the OFF or ACC states and when the GEM detects the driver door is ajar
from the driver door ajar circuits. Refer to the Chime Duration Table in this section for audible output,
duration time, and priority ratings.
Airbag Warning Chime
The airbag warning chime activates when the GEM detects the ignition switch circuits are in the RUN
state and when the GEM detects a chime is requested from the airbag system circuit. Refer to the
Chime Duration Table for audible output, duration time, and priority ratings.
Door Ajar Warning Chime
The door ajar warning chime activates when the GEM detects the ignition switch circuits are in the
RUN state and when the GEM detects the driver or passenger door is ajar from the driver and
passenger door ajar circuits. Refer to the Chime Duration Table in this section for audible output,
duration time, and priority ratings.
Headlamps Left on Warning Chime
The headlamps left on warning chime activates when the GEM detects the ignition switch circuits are
in the KEYOUT state, when the GEM detects the driver door is ajar from the driver door ajar circuit, SECTION 413-
09: Warning Devices 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F048, or equivalent
diagnostic tool Klj . 1 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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CJB FUSE 28 (15A)
z
Disconnect: CJB Fuse 28 (15A).
z Measure the voltage between CJB fuse 28 (15A), pin 1,
harness side and ground while cycling the ignition switch
through all positions.
z Is the voltage greater than 10 volts in the RUN and START
positions only? Yes
GO to
B5 .
No
REPAIR the CJB.
REPEAT the self- test.
CLEAR the DTCs. B5 CHECK GEM INPUT VOLTAGE FROM IGNITION SWITCH AT
CJB FUSE 32 (15A) z
Disconnect: CJB Fuse 32 (15A).
z Measure the voltage between CJB fuse 32 (15A), pin 1,
harness side and ground while cycling the ignition switch
through all positions.
z Is the voltage greater than 10 volts in the RUN and ACC
positions only? Yes
GO to
B6 .
No
REPAIR the CJB.
REPEAT the self- test.
CLEAR the DTCs. B6 CHECK GEM VOLTAGE INPUT CIRCUITS FOR OPEN —
IGNITION SWITCH CIRCUIT 911 (WH/LG) z
Disconnect: CJB Fuse 28 (15A).
z Disconnect: GEM C201e.
z Insert the ignition key. Measure the resistance between GEM
C201e pin 8, circuit 911 (WH/LG), harness side and CJB Fuse
28 (15A) pin 2, circuit 911 (WH/LG), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B7 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B7 CHECK GEM VOLTAGE INPUT CIRCUITS FOR OPEN —
IGNITION SWITCH CIRCUIT 1002 (BK/PK) Klj . 7 ba
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z
Measure the resistance between GEM C201e pin 22, circuit
1002 (BK/PK), harness side and CJB Fuse 32 (15A), pin 2,
circuit 1002 (BK/PK), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B8 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B8 CHECK GEM INPUT CIRCUIT FOR OPEN —
KEY-IN-
IGNITION SWITCH CIRCUIT 158 (BK/PK) z
Measure the resistance between GEM C201e pin 9, circuit
158 (BK/PK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
B9 .
No
REPAIR circuit 158
(BK/PK) and key-in-
ignition switch for failure.
REFER to Switch — Key -
In - Ignition Warning .
REPEAT the self- test.
CLEAR the DTCs. B9 CHECK GEM VOLTAGE INPUT CIRCUITS FOR SHORT TO
POWER — IGNITION SWITCH CIRCUITS 911 (WH/LG), AND 1002
(BK/PK) z
Key in OFF position.
z Disconnect: CJB Fuse 28 (15A).
z Disconnect: CJB Fuse 32 (15A).
z Disconnect: GEM C201e.
z Remove the ignition key. Measure the voltage between GEM
C201e pin 8, circuit 911 (WH/LG), harness side and ground,
and between GEM C201e pin 22, circuit 1002 (BK/PK),
harness side and ground.
z Are the voltages greater than 10 volts? Yes
REPAIR the circuit in
question. REPEAT the
self-
test. CLEAR the
DTCs.
No
GO to B10 .
B10 CHECK GEM INPUT CIRCUIT FOR SHORT TO GROUND
—-
KEY- IN-IGNITION SWITCH CIRCUIT 158 (BK/PK) z
Disconnect: GEM C201e.
z Remove the ignition key. Measure the resistance between
GEM C201e pin 9, circuit 158 (BK/PK), harness side and Yes
GO to
B11 . Klj . 8 ba
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PINPOINT TEST C: A CHIME DOES NOT OPERATE CORRECTLY—
AIR BAG ground.
z Is the resistance greater than 10,000 ohms? No
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs. B11 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 -
10 . CLEAR the DTCs.
REPEAT the GEM self-
test.
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
C1 CHECK CONTINUOUS DTCS AND RESTRAINT CONTROL
MODULE (RCM) z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
RCM On- Demand Self- Test.
z Carry out Continuous DTCs and On Demand RCM Self-
Tests.
z Are any RCM DTCs received? Yes
REFER to
Section 501 - 20B .
No
GO to C2 .
C2 CHECK IGNITION STATES
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
C3 .
No
Go To Pinpoint Test B .
C3 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
C4 .
No Klj . 9 ba
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GO to
C8 .
C4 CHECK GEM INPUT FROM RCM —
AIR BAG WARNING
CHIME z
Key in OFF position.
z Disconnect: RCM C2041.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID ABCHIME.
z Does the GEM PID ABCHIME read ON? Yes
GO to
C5 .
No
GO to C6 .
C5 CHECK CIRCUIT 1083 (LB/BK) FOR SHORT TO GROUND
z
Disconnect: RCM C2041.
z Disconnect: GEM C201e.
z Measure resistance between GEM C201e pin 10, circuit
1083 (LB/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
C8 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. C6 CHECK CIRCUIT 1083 (LB/BK) FOR SHORT TO POWER
z
Disconnect: RCM C2041e.
z Disconnect: GEM C201e.
z Measure the voltage between GEM C201e pin 10, circuit
1083 (LB/BK), harness side and ground.
z Is voltage greater than 10 volts? Yes
REPAIR the circuit. REPEAT
the self-
test. CLEAR the
DTCs.
No
GO to C7 .
C7 CHECK CIRCUIT 1083 (LB/BK) FOR OPEN
z
Disconnect: RCM C2041e.
z Disconnect: GEM C201e.
z Measure the resistance between GEM C201e pin 10, circuit
1083 (LB/BK), harness side and RCM C2041e pin 26,
circuit 1083 (LB/BK), harness side. Yes
GO to
C8 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 10 ba
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