high beam FORD MUSTANG 2003 User Guide

PINPOINT TEST C: THE HIGH BEAMS ARE INOPERATIVE z
Are the voltages greater than 10 volts? B2 CHECK CIRCUIT 13 (RD/BK) FOR OPEN
z
Disconnect: Multifunction Switch C202a.
z Measure the resistance between multifunction switch C202a
Pin 13, Circuit 13 (RD/BK), harness side and CJB Fuse 4
and Fuse 10.
z Are the resistances less than 5 ohms? Yes
INSTALL a new
multifunction switch;
REFER to
Section 211 - 05 .
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 CIRCUIT 12 (LG/BK)
z
Disconnect: LH Headlamp C1021.
z Measure the resistance between LH headlamp C1021 Pin
2, Circuit 12 (LG/BK), harness side and CJB Fuse 38 (20A).
z Is the resistance less than 5 ohms? Yes
RECONNECT the LH
headlamp (13008). GO to
C2
.
No
REPAIR the circuit. TEST
the system for normal
operation. C2 CHECK THE VOLTAGE TO CJB FUSE 38 (20A)
z
Place the headlamp switch in the ON position.
z Place the multifunction switch in the high beam position.
z Measure the voltage between CJB Fuse 38 (20A) and
ground. Yes
Go To Pinpoint Test E
.
No Klj . 4 ba
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PINPOINT TEST E: ONE HIGH BEAM HEADLAMP IS INOPERATIVE
PINPOINT TEST F: THE HEADLAMPS ARE ON CONTINUOUSLY
Test Step Result / Action to Take
E1 CHECK THE VOLTAGE TO THE INOPERATIVE HEADLAMP
BULB z
Key in OFF position.
z Disconnect: Inoperative Headlamp.
z Place the headlamp switch in the ON position.
z Place the multifunction switch in the high beam position.
z Measure the voltage between LH headlamp C1021 Pin 2,
Circuit 12 (LG/BK), or RH headlamp C1041 Pin 2, Circuit 12
(LG/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new headlamp
bulb; REFER to
Bulb —
Headlamp in this section.
TEST the system for
normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Test Step Result / Action to Take
F1 CHECK THE HEADLAMP SWITCH
z
Key in OFF position.
z Disconnect: Headlamp Switch C205.
z Are the headlamps on? Yes
GO to
F2 .
No
INSTALL a new headlamp
switch; REFER to Lamp Switch — Headlamp in this
section. TEST the system for
normal operation. F2 CHECK THE MULTIFUNCTION SWITCH
z
Disconnect: Multifunction Switch C202a.
z Are the headlamps on? Yes
GO to
F4 .
No
GO to F3 .
F3 CHECK CIRCUIT 15 (RD/YE) FOR SHORT TO POWER
z
Measure the voltage between multifunction switch
C202a Pin 15, Circuit 15 (RD/YE), harness side and
ground. Yes
REPAIR the circuit. TEST the
system for normal operation.
No
INSTALL a new multifunction
switch; REFER to
Section 211 -
05 . TEST the system for
normal operation. Klj . 6 ba
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DIAGNOSIS AND TESTING
Fog Lamps
Refer to Wiring Diagrams Cell
86 , Fog Lamps for schematic and connector information.
Principles of Operation
The fog lamps will only illuminate when the low beam or parking lamps are illuminated. Voltage from
the parking lamp circuit is used to activate the fog lamp relay when the fog lamp switch is ON. Voltage
from the high beam headlamp circuit will activate the fog lamp interrupt relay. When the fog lamp
interrupt relay is active, the ground path is removed from the fog lamp relay, turning off the fog lamps.
Inspection and Verification 1. Verify the customer concern by operating the fog lamps.
2. Visually inspect for the following obvious signs of mechanical and electrical damage.
3. If the concern is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged headlamp switch (11654)
z Damaged fog lamp switch
z Damaged multifunction switch
(13K359) z
Blown battery junction box (BJB) Fuse 27
(20A)
z Blown central junction box (CJB) Fuse 38
(20A)
z Damaged wiring harness
z Loose or corroded connections
z Damaged fog lamp relay
z Damaged fog lamp interrupt relay
z Damaged fog lamp
Symptom Chart Klj . 1 ba
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z
Check that the vehicle is on level ground.
z If the vehicle is equipped with air suspension, make sure that the switch is on.
2. NOTE: The vertical wall or screen must be a minimum of 2.4 meters (8 feet) wide.
Park the vehicle on a level surface approximately 7.6 meters (25 feet) from the vertical wall or
screen directly in front of it.
3. NOTE: The center of the lamp is marked by a 3 mm (0.12 in) circle on the headlamp lens.
Mark a horizontal reference line on the vertical wall or screen. 1. Measure the center of the headlamp height to ground and record.
2. Make a 2.4 meter (8 foot) horizontal mark (masking tape) on the vertical wall or screen at the same distance from the ground as previously recorded.
4. NOTE: This procedure should be done in a dark environment to effectively see the headlamp
beam pattern.
Turn on the low beam headlamps to illuminate the wall or screen and open the hood.
5. NOTE: For SAE type headlamps, the appearance of the beam pattern may vary between
vehicles.
On the wall or screen, locate the high intensity area of the beam pattern. Place the top edge of
the high intensity zone even with the horizontal reference line.
VOR type headlamps 6. NOTE: The appearance of the VOR beam pattern may vary between vehicles.
Identify at the top edge of this high intensity area a distinct horizontal cutoff in the beam pattern.
If the top edge of this cutoff is not even with the horizontal reference line, the headlamp beam will need to be adjusted. Klj . 2 ba
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VOL type headlamps
7. For VOL type headlamps, there will be a distinct cutoff in the left portion of the beam pattern. The edge of this cutoff should be positioned 50.2 mm (2 in) below the horizontal reference line.
1. Horizontal reference line.
2. Top edge of the beam pattern.
3. High intensity zone.
Mechanical Aiming 1. For the mechanical aiming procedure, refer to the appropriate mechanical headlamp aimer instruction manual. Klj . 3 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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Pinpoint Test J: LFC 34/DTC B1934 —
Driver Air Bag Circuit Resistance Low
Normal Operation
The restraints control module (RCM) monitors the resistance of the driver air bag ignitor by measuring
the resistance between pins 3 and 4. If the RCM detects low resistance between these pins, it will
store a diagnostic trouble code (DTC) B1934 in memory and flash a lamp fault code (LFC) 34 (or
higher priority code if one exists) on the air bag indicator.
Possible Causes
Driver air bag low resistance can be caused by:
za short in the clockspring windings.
z a short in the wiring harness.
z a low resistance in the driver air bag module.
z an RCM internal concern.
z worn or damaged short bar or camming beam.
PINPOINT TEST J: LFC 34/DTC B1934 — DRIVER AIR BAG CIRCUIT
RESISTANCE LOW Trouble Code
(DTC) Priority
Table in this
section for pinpoint
test direction.
No
RECONNECT the
system.
REACTIVATE the
system. PROVE
OUT the system.
REFER to
Air Bag Supplemental
Restraint System
(SRS) in this
section. CLEAR all
DTCs. Test Step Result / Action to
Take J1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test. Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the Klj . 26 ba
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Pinpoint Test K: LFC 35/DTC B1935 —
Passenger Air Bag Circuit Resistance Low
Normal Operation
The restraints control module (RCM) monitors the resistance of the passenger air bag ignitor by
measuring the resistance between pins 6 and 7. If the RCM detects low resistance between these
pins, it will store a diagnostic trouble code (DTC) B1935 in memory and flash a lamp fault code (LFC)
35 (or higher priority code if one exists) on the air bag indicator.
Possible Causes
Passenger air bag low resistance can be caused by:
za short in the wiring harness.
z a low resistance in the passenger air bag module.
z an RCM internal concern.
z a worn or damaged connector shorting bar or camming beam.
PINPOINT TEST K: LFC 35/DTC B1935 — PASSENGER AIR BAG
CIRCUIT RESISTANCE LOW (SRS) in this
section. CLEAR all
DTCs. Test Step Result / Action to
Take K1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1935 retrieved during the on- demand self test? Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the
on-
demand self
test. GO to K2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
K4 .
K2 CHECK THE PASSENGER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section. Yes
GO to
K3 .
No
INSTALL a new Klj . 29 ba
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