AC system FORD MUSTANG 2003 Workshop Manual

PINPOINT TEST S: THE INDIVIDUAL REVERSING LAMP IS
INOPERATIVE z
If equipped with M/T, measure the resistance between
reversing lamp switch C169, Circuit 140 (BK/PK), harness
side and ground.
z Is the resistance less than 5 ohms? system for normal operation.
No
GO to
R3 .
R3 CHECK REVERSING LAMPS GROUND
z
Disconnect: Inoperative Reversing Lamp.
z Measure the resistance between LH reversing lamp C451,
Circuit 1205 (BK), or RH reversing lamp C461, Circuit
1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
REPAIR Circuit 140 (BK/PK)
for open. TEST the system for
normal operation.
No
REPAIR the circuit. TEST the
system for normal operation.
Test Step Result / Action to
Take S1 CHECK REVERSING LAMPS GROUND
z
Key in OFF position.
z Disconnect: Inoperative Reversing Lamp.
z Measure the resistance between LH reversing lamp C451, Circuit
1205 (BK), or RH reversing lamp C461, Circuit 1205 (BK),
harness side and ground. Yes
REPAIR Circuit 140
(BK/PK) for open.
TEST the system for
normal operation. Klj . 3 ba
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PINPOINT TEST T: THE REVERSING LAMPS ARE ON
CONTINUOUSLY z
Is the resistance less than 5 ohms? No
REPAIR the circuit.
TEST the system for
normal operation.
Test Step Result / Action to Take
T1 CHECK THE CONTINUITY OF THE
DTR SENSOR (A/T) OR THE
REVERSING LAMP SWITCH (M/T) z
Key in OFF position.
z Disconnect: DTR Sensor C167
(A/T).
z Disconnect: Reversing Lamp Switch
C169 (M/T).
z Set the parking brake.
z Key in ON position.
z Select REVERSE.
z Are the reversing lamps
illuminated? Yes
REPAIR Circuit 140 (BK/PK) for short to battery.
TEST the system for normal operation.
No
INSTALL a new DTR sensor (A/T) or reversing lamp
switch (M/T); REFER to
Section 307 - 01 ,
Section 308 - 03A , or
Section 308 - 03B . TEST the system for
normal operation. Klj . 4 ba
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DESCRIPTION AND OPERATION
Interior Lighting
The interior lighting system consists of the following:
zmap/dome lamp assembly
z rear- high mount/cargo lamp assembly
z dimmer switch
z door ajar switch (located on the door latches)
z rear view mirror interior lamp (convertible only)
z courtesy lamp
z vanity mirror lamp assembly
z transmission range indicator
SECTION 417-
02: Interior Lighting 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Interior Lighting
Refer to Wiring Diagrams Cell
111 , Remote Control Alarm and Lock System for schematic and
connector information.
Refer to Wiring Diagrams Cell 59 , Generic Electronic Module for schematic and connector
information.
Refer to Wiring Diagrams Cell 89 , Courtesy Lamps for schematic and connector information.
Principles of Operation
Battery Saver
The battery saver feature provides automatic shut- off of power to demand and courtesy lamp circuitry.
When the generic electronic module (GEM) detects the ignition switch circuits are in the key OFF or
removed ignition key positions, power will be disabled after individual time- out periods of 30 minutes
for the demand lamps, and 10 minutes for the courtesy lamps. However, the time- out period for the
courtesy lamps changes to 30 minutes when the GEM detects that the luggage compartment lid is ajar
by means of the luggage compartment lid ajar circuit, or if the dome lamp is switched on by means of
the dome lamp circuit. When the GEM detects that the ignition switch is in the RUN, ACC, or START
positions, the battery saver feature is disabled.
The battery saver timer for the demand lamps is reset when the GEM detects that the ignition switch is
in the OFF or key out positions or when the GEM detects any one of the following conditions:
zthe driver or passenger door becomes ajar, as detected by the door ajar circuit
z the luggage compartment lid becomes ajar, as detected by the luggage compartment lid ajar
circuit
z the dome lamp switch is activated, as detected by the dome lamp switch circuit
The battery saver timer for the courtesy lamps is reset when the GEM detects that the ignition switch is
in the OFF or key out positions or when the GEM detects the driver or passenger door becomes ajar SECTION 417-
02: Interior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051 Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Klj . 1 ba
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as detected by the door ajar circuit. For vehicles equipped with the remote keyless entry feature, any
signal the GEM detects when a valid remote transmitter button is depressed will reset both the
demand and courtesy lamp battery saver timers. This battery saver relay then restores power to both
the demand and courtesy lamp circuits.
Base Courtesy and Extended Lighting
The base courtesy lighting feature provides interior lighting for the convenience of the vehicle's
occupants. The courtesy lamps consist of the map/dome lamps for the coupe and the map lamps for
the convertible. All lamps designated as courtesy lamps will be illuminated whenever the GEM detects
that the driver or passenger doors become ajar, by means of the driver or passenger door ajar circuits.
The courtesy lamps will also be illuminated when the GEM detects that the dome lamp switch has
been activated, by means of the dome lamp switch circuit.
The extended courtesy lighting feature provides temporary extended illumination of the courtesy lamps
after the customer has entered the vehicle. The courtesy lamps will remain illuminated for 25 seconds
after the GEM detects that the driver and passenger doors are closed, as detected by the door ajar
circuits. The extended courtesy lighting feature will be terminated after the 25 second time-
out period,
or if the GEM detects that the ignition switch has been moved from the OFF position to either the RUN,
ACC, or START positions.
Demand Lighting
The GEM does not provide any special features to the demand lighting group with the exception of
providing a power source when the battery saver feature is active. The demand lighting group consists
of the luggage compartment lamp, the driver and passenger vanity mirror lamps, and the map lamps.
Illuminated Entry with Remote Keyless Entry
The illuminated entry with remote keyless entry feature, provides power to the courtesy lamps when
the remote transmitter is used. When the GEM detects that the ignition switch is in the OFF or key out
positions, and it detects that a valid remote transmitter unlock button has been depressed, power to
the courtesy lamps will be enabled. The courtesy lamp circuit will remain powered until one of the
following occurs:
zThe GEM detects that the ignition switch has been moved from the OFF, to the RUN, START,
or ACC position.
z The GEM detects any valid remote transmitter lock button is depressed.
z The courtesy lamp circuit has been powered for 25 seconds.
If the GEM detects any valid remote transmitter unlock button has been depressed, and the ignition
switch is in the OFF or key out position during the 25 second time- out, the courtesy lamp circuits will
remain powered for an additional 25 seconds.
Inspection and Verification
1. The interior lighting system is a generic electronic module (GEM) controlled system.
2. Verify the customer concern by operating the interior lighting system.
3. Visually inspect for the following obvious signs of mechanical and electrical damage. Klj . 2 ba
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4. If the concern remains after the inspection, connect the scan tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the scan 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 scan tool still does not communicate with the vehicle, refer to the scan tool manual.
6. Carry out the DATA LINK DIAGNOSTIC TEST. If the scan 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 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 GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index Visual Inspection Chart Mechanical Electrical
z
Switch(es) z
CJB Fuses:
„7 (20A)
„ 32 (15A)
„ 39 (5A)
z Wiring harness
z Connections
z Lamps
z Circuitry
GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1322 Driver Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door
Circuit Short to Ground GEM REFER to
Section 417 - 02 .
B1342 ECU Is Defective GEM CLEAR the DTC. Retrieve the DTCs. If DTC B1342 is
retrieved, INSTALL a new GEM. For additional information, REFER to Section 419 - 10 .
B1397 Power Door unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 . Klj . 3 ba
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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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PINPOINT TEST B: THE COURTESY LAMPS ARE INOPERATIVE z
Is the resistance less than 5 ohms? A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between GEM C201b pin 2, 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
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
positions? Yes
GO to
B2 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
B2 CHECK THE DOOR AJAR INPUT TO THE GEM
z
Monitor the GEM PID D_DOOR, and P_DOOR, while
opening and closing the driver and passenger doors.
z Do the GEM PIDS D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
B3 .
No
REFER to Section 413 -
09 .
B3 CHECK THE DOME LAMP SWITCH STATUS INPUT TO THE
GEM — MONITOR THE GEM PID DOMESW z
Monitor the GEM PID DOMESW, while activating, and
deactivating the dome lamp switch.
z Does the GEM PID DOMESW agree with the dome lamp
switch position? Yes
GO to
B4 .
No
GO to B13 .
B4 CHECK THE LUGGAGE COMPARTMENT LID AJAR INPUT
TO THE GEM — MONITOR THE GEM PID DECKLID Klj . 7 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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