ignition FORD MUSTANG 2003 Workshop Manual

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 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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PINPOINT TEST D: THE DOOR AJAR CHIME DOES NOT OPERATE
CORRECTLY z
Is the resistance less than 5 ohms? C8 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
D1 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
D2 .
No
GO to Pinpoint Test B .
D2 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
D3 .
No
GO to D17 .
D3 CHECK GEM INPUT —
DRIVER 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
D4 .
No
GO to D5 .
D4 CHECK GEM INPUT —
PASSENGER DOOR AJAR CIRCUIT Klj . 11 ba
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E2 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
E3 .
No
Go To Pinpoint Test B .
E3 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
E4 .
No
GO to E9 .
E4 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
E5 .
No
GO to Pinpoint Test D .
E5 MONITOR EXTERIOR LAMP INPUT FOR CORRECT
STATE z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while triggering the
headlamp switch ON and OFF.
z Do the GEM PID PARK_SW values indicate ON and
OFF correctly? Yes
GO to
E9 .
No
GO to E6 .
E6 CHECK EXTERIOR LAMP INPUT CIRCUIT FOR SHORT
TO POWER — GEM PID PARK_SW z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while opening and
closing the driver door.
z Does the GEM PID PARK_SW value always indicate
ON? Yes
GO to
E8 .
No
GO to E7 .
E7 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Key in OFF position.
z Disconnect: GEM C201c.
z Disconnect: Headlamp Switch C205.
z Measure the resistance between GEM C201c pin 7, circuit
14 (BN), harness side and headlamp switch C205 pin R,
circuit 14 (BN), harness side. Yes
GO to
E9 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 16 ba
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PINPOINT TEST F: THE SAFETY BELT WARNING CHIME DOES NOT
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? E8 TEST CIRCUIT 14 (BN) FOR SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201c.
z Set the headlamp switch in the OFF position. Measure the
voltage between GEM C201c pin 7, circuit 14 (BN),
harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit. REPEAT
the self-
test. CLEAR the
DTCs.
No
GO to E9 .
E9 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
F1 CHECK IGNITION STATES
NOTE:
Verify the belt minder is activated before
diagnosing.
z Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID. Yes
GO to
F2 .
No
Go To Pinpoint Test B . Klj . 17 ba
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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? F2 DETERMINE IF THE GEM IS RECEIVING CORRECT
SAFETY BELT SWITCH STATUS z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT read OUT and IN
correctly? Yes
GO to
F3 .
No
GO to F5 .
F3 CHECK THE 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
F4 .
No
GO to F11 .
F4 CHECK THE SAFETY BELT WARNING LAMP OPERATION
z
Cycle the ignition switch from OFF to RUN while monitoring
the instrument cluster safety belt indicator lamp.
z Does instrument cluster safety belt indicator lamp
illuminate for approximately three seconds? Yes
GO to
F11 .
No
REFER to Section 413 - 01 .
F5 DETERMINE IF CIRCUIT 85 (BN/LB) IS OPEN OR
SHORTED TO GROUND z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT, while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT value indicate OUT with
the driver safety belt buckled? Yes
GO to
F6 .
No
GO to F8 .
F6 ISOLATE THE SHORT TO GROUND ON CIRCUIT 85
(BN/LB) z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT.
z Does the GEM PID D_SBELT value indicate IN? Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
F7 .
F7 CHECK CIRCUIT 85 (BN/LB) FOR A SHORT TO GROUND
BETWEEN GEM AND SAFETY BELT SWITCH z
Disconnect: GEM C201d.
z Measure the resistance between GEM C201d pin 8, circuit
85 (BN/LB), harness side and ground. Yes
GO to
F11 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 18 ba
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