battery FORD MUSTANG 2003 Workshop Manual

battery. Failure to follow this caution will result in the GEM storing many erroneous DTCs and
may result in the GEM exhibiting erratic operation after installation.
CAUTION: Be careful when probing the central junction box (CJB), battery junction box
(BJB), or any connectors. Damage will result to the connector receptacle if the probe being
used is too large.
CAUTION: Electronic modules are sensitive to static electrical charges. 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.
NOTE: Complete the entire pinpoint test related to the symptom before installing a new GEM.
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE 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. A1 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 2 400 (LB/BK)
C201a 3 1006 (DG/WH)
C201b 1 1001 (WH/YE)
C201b 4 193 (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 reistance between the GEM C201b pin 2, 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 . 6 ba
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z
Monitor the GEM PID DECKLID, while opening and closing
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the dome switch
position? Yes
GO to
B5 .
No
GO to B16 .
B5 CHECK THE COURTESY LAMP CIRCUITS
z
Close the luggage compartment lid and all doors are closed.
z Turn the dome and map lamp switches to the off position.
z Are the courtesy lamps illuminated? Yes
GO to
B12 .
No
GO to B6 .
B6 CHECK THE GEM CONTROL OF THE COURTESY LAMPS
z
Trigger the GEM active command COURTESYL ON and then
OFF.
z Do the courtesy lamps illuminate when the GEM active
command COURTESYL ON is triggered, and go out when
the GEM active command COURTESYL OFF is triggered? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
GO to B7 .
B7 CHECK THE GEM FOR AN INTERNAL FAULT
z
Trigger the GEM active command COURTESYL ON, then
OFF.
z Can an audible click be heard coming from the GEM,
while triggering the active command COURTESYL ON? Yes
GO to
B8 .
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. B8 CHECK CIRCUIT 1034 (BK/WH) FOR VOLTAGE
z
Disconnect the dome lamp C929 (coupe) or map lamp C978
(convertible)
z Trigger the GEM active command COURTESYL ON.
z Measure the voltage between dome/map lamp C929 (coupe)
Pin 3 or map lamp C978 (convertible) Pin 4, Circuit 1034
(BK/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
B11 .
No
GO to B9 .
B9 CHECK CIRCUIT 1006 (DG/WH) FOR OPEN
NOTE:
Verify battery voltage at CJB Fuse 7 (20A) before
carrying out this test.
z Disconnect: GEM C201a.
z Measure the voltage between GEM C201a Pin 1, Circuit 1006
(DG/WH), harness side and ground. Yes
GO to
B10 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Klj . 8 ba
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z
Is the voltage greater than 10 volts? B10 CHECK CIRCUIT 1034 (BK/WH) FOR OPEN
z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c Pin 3, Circuit
1034 (BK/WH), harness side and dome/map lamp C929
(coupe) Pin 3 or map lamp C978 (convertible) Pin 4, Circuit
1034 (BK/WH), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B11 CHECK CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between dome/map lamp C929
(coupe) Pin 2 or map lamp C978 (convertible) Pin 1, Circuit
1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
dome/map lamp
assembly. For additional
information, REFER to
Lamp Assembly
—
Map/Dome .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B12 CHECK CIRCUIT 1034 (BK/WH) FOR SHORT TO BATTERY
z
Measure the voltage between GEM C201c Pin 3, Circuit 1034
(BK/WH), harness side and ground. Yes
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs.
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. Klj . 9 ba
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z
Is the voltage greater than 10 volts? B13 CHECK THE COURTESY LAMP OPERATION —
MONITOR
THE GEM PID DOMESW z
Monitor the GEM PID DOMESW, while moving the interior
lamp switch from the OFF to the ON position.
z Does the GEM PID DOMESW value always indicate ON? Yes
GO to
B15 .
No
GO to B14 .
B14 CHECK CIRCUIT 706 (GY) FOR OPEN
z
Disconnect: GEM C201e.
z Measure the voltage between GEM C201e Pin 21, Circuit 706
(GY), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B15 CHECK CIRCUIT 706 (GY) FOR SHORT TO BATTERY
z
Measure the voltage between GEM C201e Pin 21, Circuit 706
(GY), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs.
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. B16 CHECK CIRCUIT 486 (BN/WH) FOR OPEN OR SHORT TO
GROUND — MONITOR THE GEM PID DECKLID z
Monitor the GEM PID DECKLID, while opening and closing
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the luggage
compartment lid position? Yes
GO to
B17 .
No
GO to B19 . Klj . 10 ba
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C4 CHECK INTERIOR LAMP SWITCH INPUT TO THE GEM —
MONITOR GEM PID DOMESW z
Monitor the GEM PID DOMESW, while moving the interior
lamp switch from the OFF to the ON position.
z Does the GEM PID DOMESW values agree with the
interior lamp switch positions? Yes
GO to
C5 .
No
GO to Pinpoint Test B .
C5 CHECK THE LUGGAGE COMPARTMENT LID AJAR INPUT
TO THE GEM — MONITOR THE GEM PID DECKLID z
Monitor the GEM PID DECKLID, while opening, and closing,
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the luggage
compartment lid position? Yes
GO to
C6 .
No
GO to Pinpoint Test B .
C6 CHECK CIRCUIT 705 (LG/OG) FOR OPEN
z
Turn on both map lamps using the switches in the rear view
mirror.
z Turn on both vanity mirror lamps.
z Open the luggage compartment lid.
z Disconnect: GEM C201c.
z Connect a fused jumper (20A) between GEM C201c Pin 4,
Circuit 705 (LG/OG), harness side and battery positive
terminal.
z Do the demand lamps illuminate? Yes
GO to
C7 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. C7 CHECK CIRCUIT 1006 (DG/WH) FOR OPEN
NOTE:
Verify battery voltage at CJB Fuse 7 (20A) before
carrying out this test.
z Disconnect: GEM C201a.
z Measure the voltage between GEM C201a Pin 1, Circuit 1006
(DG/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. C8 CHECK CIRCUIT 705 (LG/OG) FOR VOLTAGE AT
INOPERATIVE DEMAND LAMP z
Key in OFF position.
z Disconnect inoperative demand lamp, dome/map C929 Yes
GO to
C9 . Klj . 13 ba
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PINPOINT TEST E: THE BATTERY SAVER DOES NOT DEACTIVATE
AFTER TIMEOUT
Test Step Result / Action to Take
E1 CHECK THE GEM CONTROL OF THE BATTERY SAVER
FUNCTION — TRIGGER THE GEM ACTIVE COMMAND BATT
SAVR ON z
Trigger the GEM active command BATT SAVR ON and then
OFF.
z Do the courtesy lamps illuminate and turn off when the
GEM active command BATT SAVR is triggered ON and
OFF? Yes
INSTALL a new GEM.
For additional
information, REFER to
Section 419
- 10 .
REPEAT the self- test.
CLEAR the DTCs.
No
GO to E2 .
E2 CHECK CIRCUITS 1034 (BK/WH), AND 705 (LG/OG), FOR
SHORT TO BATTERY z
Disconnect: GEM C201c.
z Measure the voltage between GEM C292 Pin 3, Circuit 1034
(BK/WH), harness side and ground; and between GEM C292
Pin 4, Circuit 705 (LG/OG), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit in
question. REPEAT the
self-
test. CLEAR the
DTCs.
No
INSTALL a new GEM.
For additional
information, REFER to
Section 419 - 10 .
REPEAT the self- test.
CLEAR the DTCs. Klj . 15 ba
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REMOVAL AND INSTALLATION
Lamp Assembly —
Map/Dome
Removal 1. Disconnect the battery ground cable.
2. Remove the lamp lens from the lamp assembly.
3. Remove the lamp assembly. 1. Remove the screws.
2. Remove the lamp assembly.
z Disconnect the electrical connectors.
Installation 1. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms
may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven
16 km (10 mi) or more to relearn the strategy.
To install, reverse the removal procedure.
SECTION 417-
02: Interior Lighting 2003 Mustang Workshop Manual Klj . 1 ba
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SPECIFICATIONS
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual Torque Specifications
Description Nm lb-
in Battery ground cable screw 8 71
Daytime running lamps control module bolts 9 80 Klj . 1 ba
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DIAGNOSIS AND TESTING
Daytime Running Lamps (DRL)
Refer to Wiring Diagrams Cell
97 , Daytime Running Lamps for schematic and connector information.
Principles of Operation
Daytime Running Lamps (DRL)
The daytime running lamps (DRL) system operates the low beam headlamps at a reduced intensity.
The DRL module (15A270) supplies pulse width modulated (PWM) voltage, approximately 75%- 92%
of battery voltage, to the low beam headlamps when the following conditions are met:
zThe parking brake control is released.
z The high beam headlamps are disabled.
z The ignition switch (11572) is in the RUN position.
The DRL module remains enabled when the low beam headlamps are turned on.
Inspection and Verification 1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. Verify the headlamps are operating correctly. Correct any concerns before proceeding to the
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged DRL module
z Damaged parking brake signal switch and
bracket (15A851) z
Blown battery junction box (BJB) Maxi-
Fuse FOG+DRL (20A)
z Damaged wiring harness
z Loose or corroded connection
z Damaged DRL module
z Damaged parking brake signal switch and
bracket Klj . 1 ba
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PINPOINT TEST B: THE DAYTIME RUNNING LAMPS ARE ON WITH
THE PARKING BRAKE SET z
Is the voltage greater than 10 volts? A5 CHECK THE DRL MODULE GROUND —
CIRCUIT 1205
(BK) z
Measure the resistance between DRL module C1030 Pin
4, Circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
A6 .
No
REPAIR the circuit. TEST the
system for normal operation. A6 CHECK THE HIGH BEAM DISABLE INPUT CIRCUIT FOR
SHORT TO BATTERY — CIRCUIT 12 (LG/BK) z
Measure the voltage between DRL module C1030 Pin 5,
Circuit 12 (LG/BK), harness side and ground.
z Is voltage indicated? Yes
REPAIR the circuit. TEST the
system for normal operation.
No
INSTALL a new DRL module.
REFER to
Module — Daytime
Running Lamps (DRL) . TEST
the system for normal
operation. Test Step Result / Action to Take
B1 CHECK THE PARKING BRAKE SWITCH
z
Key in OFF position.
z Disconnect: Parking Brake Switch C306.
z Connect a 10A fused jumper wire between parking brake
switch C306, Circuit 22 (LB/BK), harness side and ground.
z Key in ON position. Yes
INSTALL a new parking
brake signal switch and
bracket. TEST the system
for normal operation.
No
GO to
B2 . Klj . 4 ba
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