2003 FORD MUSTANG fuse

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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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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z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID P_DR_SW while opening and closing
the passenger door.
z Do the GEM PID P_DR_SW values indicate CLOSED and
AJAR correctly? Yes
GO to
D17 .
No
GO to D11 .
D5 CHECK CIRCUIT 765 (YE/BK) AND DRIVER DOOR AJAR
SWITCH FOR OPEN OR SHORT TO GROUND 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 Does the GEM PID D_DR_SW value indicate AJAR with
driver door closed? Yes
GO to
D6 .
No
GO to D8 .
D6 ISOLATE SHORT TO GROUND ON CIRCUIT 765 (YE/BK)
z
Disconnect: Driver Door Ajar Switch C526.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW.
z Does GEM PID D_DR_SW read CLOSED? Yes
INSTALL a new driver door
ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
GO to D7 .
D7 CHECK CIRCUIT 765 (YE/BK) FOR SHORT TO GROUND
BETWEEN GEM AND DRIVER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 13, circuit
765 (YE/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D8 CHECK CIRCUIT 765 (YE/BK) FOR OPEN
z
Disconnect: Driver Door Ajar Switch C526.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between driver door ajar
switch C526 pin 2, circuit 765 (YE/BK), harness side and
ground while monitoring GEM PID D_DOOR. Yes
GO to
D10 .
No
GO to D9 . Klj . 12 ba
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z
Disconnect: Passenger Door Ajar Switch C602.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID P_DR_SW.
z Does GEM PID P_DR_SW read CLOSED? Yes
INSTALL a new passenger
door ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
GO to D13 .
D13 CHECK CIRCUIT 761 (GN/RD) FOR SHORT TO GROUND
BETWEEN GEM AND PASSENGER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 5, circuit
761 (GN/RD), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D14 ISOLATE OPEN CIRCUIT 761 (GN/RD)
z
Disconnect: Passenger Door Ajar Switch C602.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between the passenger
door ajar switch C602 pin 2, circuit 761 (GN/RD), harness
side and ground while monitoring the GEM PID P_DR_SW.
z Does GEM PID P_DR_SW read AJAR with jumper wire
installed? Yes
GO to
D16 .
No
GO to D15 .
D15 CHECK FOR OPEN ON CIRCUIT 761 (GN/RD) BETWEEN
GEM AND PASSENGER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 5, circuit
761 (GN/RD), harness side and passenger door ajar switch
C602 pin 2, circuit 761 (GN/RD), harness side. Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Klj . 14 ba
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z
Is the resistance greater than 10,000 ohms? F8 ISOLATE OPEN ON CIRCUIT 85 (BN/LB)
z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between safety belt
switch C323 pin 2, circuit 85 (BN/LB), harness side and
ground while monitoring GEM PID D_SBELT.
z Does GEM PID GEM PID D_SBELT read OUT with
jumper wire installed? Yes
GO to
F10 .
No
GO to F9 .
F9 CHECK CIRCUIT 85 (BN/LB) FOR OPEN BETWEEN GEM
AND SEATBELT SWITCH z
Disconnect: Safety Belt Switch C323.
z Disconnect: GEM C201b.
z Measure the resistance between GEM C201b pin 8, circuit
85 (BN/LB), harness side and safety belt switch C323 pin 2,
circuit 85 (BN/LB), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
F11 .
No
REPAIR the circuit. CLEAR
the DTCs. TEST the system
for normal operation. F10 CHECK CIRCUIT 1205 (BK) FOR AN OPEN CIRCUIT
BETWEEN SAFETY BELT SWITCH AND GROUND z
Disconnect: Safety Belt Switch C323.
z Measure the resistance between the safety belt switch
C323 pin 1, circuit 1205 (BK), harness side and ground. Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs. Klj . 19 ba
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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 ba
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Pinpoint Tests
CAUTION: Do not make jumper connections except as directed. Incorrect connections
may damage the voltage regulator test terminals, fuses, or fuse links.
CAUTION: Do not allow any metal object to come in contact with the generator housing
and internal diode cooling fins.
NOTE: All voltage measurements are referenced to the negative (- ) battery post unless otherwise
specified. PINPOINT TEST A: BATTERY IS DISCHARGED OR VOLTAGE IS Symptom Chart
Condition
Possible Sources Action
z Battery is discharged or voltage is
low z
Circuitry.
z High key- off current
drain(s).
z Battery.
z Generator. z
Go To Pinpoint
Test A .
z The charging system warning
indicator is on with the engine
running (the system voltage does
not increase) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test B .
z The system overcharges (the
battery voltage is greater than 15.5
volts) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test C .
z The charging system warning
indicator is on with the engine
running and the battery increases
voltage z
Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test D .
z The charging system warning
indicator is off with the ignition
switch in the RUN position and the
engine off z
Bulb.
z Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test E .
z The charging system warning
indicator flickers or is intermittent z
Central junction box
(CJB) fuse 5 (15A).
z Generator
connector
unplugged (C102a).
z Circuitry.
z Generator. z
Go To Pinpoint
Test F .
z The generator is noisy zBolts or brackets.
z Drive belt.
z Generator or pulley. z
Go To Pinpoint
Test G .
z Radio interference zGenerator.
z Circuitry.
z In-vehicle
entertainment
system. z
Go To Pinpoint
Test F . Klj . 4 ba
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