FORD MUSTANG 2003 Workshop Manual

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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DESCRIPTION AND OPERATION
Daytime Running Lamps (DRL)
The daytime running lamp (DRL) system consists of a daytime running lamp module and bracket
assembly (15A270). The module is located on the front bumper reinforcement.
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual 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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next step. For additional information, refer to
Section 417 - 01 .
4. Verify the parking brake control is fully released.
5. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
6. If the concern is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: THE DAYTIME RUNNING LAMPS ARE
INOPERATIVE Symptom Chart Condition
Possible Sources Action
z The daytime running lamps are
inoperative z
BJB Maxi- Fuse
FOG+DRL (20A).
z Circuitry.
z Parking brake
signal switch and
bracket.
z DRL module. z
GO to
Pinpoint Test A .
z The daytime running lamps are
on with the parking brake set z
Circuitry.
z Parking brake
signal switch and
bracket.
z DRL module. z
GO to
Pinpoint Test B .
z The daytime running lamps are
on with the ignition switch off z
Circuitry.
z Ignition switch.
z DRL module. z
GO to
Pinpoint Test C .
z The low beam headlamps are on
at full intensity in DRL mode z
Circuitry.
z Headlamp switch.
z DRL module. z
GO to
Pinpoint Test D .
z The low beam headlamps are on
at reduced intensity with the
headlamp switch on z
Circuitry.
z Headlamp switch. z
REFER to
Section 417 -
01 .
Test Step Result / Action to Take
A1 CHECK THE PARKING BRAKE SWITCH SIGNAL
CIRCUIT TO THE DRL MODULE FOR SHORT TO GROUND NOTE:
Verify the parking brake control is fully released
for this step.
z Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the resistance between DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side and ground. Yes
GO to
A3 .
No
GO to A2 . Klj . 2 ba
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z
Is the resistance greater than 10,000 ohms? A2 CHECK THE PARKING BRAKE SWITCH
z
Disconnect: Parking Brake Switch C306.
z Measure the resistance between DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
INSTALL a new parking brake
signal switch and bracket.
TEST the system for normal
operation.
No
REPAIR the circuit. TEST the
system for normal operation.
A3 CHECK VOLTAGE TO THE DRL MODULE
z
Measure the voltage between DRL module C1030 Pin 2,
Circuit 477 (LB/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A4 .
No
REPAIR the circuit. TEST the
system for normal operation. A4 CHECK IGNITION SENSE INPUT
z
Key in ON position.
z Measure the voltage between DRL module C1030 Pin 3,
Circuit 298 (VT/OG), harness side and ground. Yes
GO to
A5 .
No
REPAIR the circuit. TEST the
system for normal operation. Klj . 3 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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PINPOINT TEST C: THE DAYTIME RUNNING LAMPS ARE ON WITH
THE IGNITION SWITCH OFF z
Do the DRL turn off? B2 CHECK THE PARKING BRAKE SWITCH SIGNAL CIRCUIT
z
Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the resistance between parking brake switch C306,
Circuit 22 (LB/BK), harness side and DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new DRL
module. REFER to
Module
— Daytime
Running Lamps (DRL) .
TEST the system for
normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE IGNITION SWITCH INPUT TO THE DRL
MODULE FOR VOLTAGE z
Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the voltage between DRL module C1030 Pin 3,
Circuit 298 (VT/OG), harness side and ground.
z Is voltage indicated? Yes
GO to
C2 .
No
INSTALL a new DRL module.
REFER to Module — Daytime
Running Lamps (DRL) . TEST
the system for normal
operation. C2 CHECK THE IGNITION SWITCH
z
Check the ignition switch; refer to the Wiring Diagrams
Cell 149.
z Is the ignition switch OK? Yes
REPAIR Circuit 298 (VT/OG)
for short to battery. TEST the
system for normal operation.
No
INSTALL a new ignition switch.
REFER to
Section 211 - 05 .
TEST the system for normal
operation. Klj . 5 ba
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PINPOINT TEST D: THE LOW BEAM HEADLAMPS ARE ON AT FULL
INTENSITY IN DRL MODE
Test Step Result / Action to Take
D1 CHECK THE LOW BEAM
HEADLAMPS INPUT z
Disconnect: DRL Module
C1030.
z Are the low beam
headlamps still on at full
intensity? Yes
REFER to
Section 417 - 01 .
No
INSTALL a new DRL module. REFER to Module —
Daytime Running Lamps (DRL) . TEST the system for
normal operation. Klj . 6 ba
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REMOVAL AND INSTALLATION
Module —
Daytime Running Lamps (DRL)
Removal
1. CAUTION: Electronic modules are sensitive to static electrical charges. If exposed
to these charges, damage can result.
Disconnect the battery ground cable.
2. Remove the daytime running lamps (DRL) module and bracket assembly (15A270). 1. Remove the nut.
2. Disconnect the electrical connector.
3. Remove the DRL module and bracket assembly.
Installation 1. CAUTION: 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 10 miles (16 km) or more to relearn the strategy.
To install, reverse the removal procedure.
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual Klj . 1 ba
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Klj . 2 ba
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