air condition FORD MUSTANG 2003 Workshop Manual

REMOVAL AND INSTALLATION
Suction Accumulator to Compressor Line —
4.6L
Removal and Installation
NOTE: Installation of a new suction accumulator is not required when repairing the air conditioning
system except when there is physical evidence of contamination from a failed A/C compressor or
damage to the suction accumulator.
1. Recover the refrigerant. For additional information, refer to Section 412 - 00 .
2. Remove the air cleaner outlet tube. For additional information, refer to Section 303 - 12 .
3. Disconnect the spring lock coupling at the suction accumulator. zDiscard the O- ring seals.
4. Disconnect the spring lock coupling at the compressor manifold. zDiscard the O- ring seals. 5. Remove the suction accumulator to compressor line. SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual Material
Item Specification
PAG Refrigerant Compressor
Oil (R-
134a Systems)
F7AZ- 19589- DA (Motorcraft YN-
12- C) WSH-
M1C231-
B Klj . 1 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

REMOVAL AND INSTALLATION
Compressor to Condenser Discharge Line —
4.6L
Removal and Installation
NOTE: Installation of a new suction accumulator is not required when repairing the air conditioning
system except when there is physical evidence of contamination from a failed A/C compressor or
damage to the suction accumulator.
1. Recover the refrigerant. For additional information, refer to Section 412 - 00 .
2. Disconnect the dual- function pressure switch electrical connector and remove the switch.
3. Remove the A/C muffler bracket nut.
4. Disconnect the fitting at the condenser. zDiscard the O- ring seal.
SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual Material
Item Specification
PAG Refrigerant Compressor
Oil (R-
134a Systems)
F7AZ- 19589- DA (Motorcraft YN-
12- C) WSH-
M1C231-
B Klj . 1 ba
32003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

REMOVAL AND INSTALLATION
Condenser to Evaporator Line
Removal and Installation
NOTE:
Installation of a new suction accumulator is not required when repairing the air conditioning
system except when there is physical evidence of contamination from a failed A/C compressor or
damage to the suction accumulator.
1. Recover the refrigerant. For additional information, refer to Section 412 - 00 .
2. Remove the air cleaner outlet tube. For additional information, refer to Section 303 - 12 .
3. Raise the vehicle. For additional information, refer to Section 100 - 02 .
4. Remove the line bracket pin- type retainer.
5. Lower the vehicle.
6. Remove the nut and disconnect the fitting at the condenser. zDiscard the O- ring seal.
SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual Material
Item Specification
PAG Refrigerant Compressor
Oil (R-
134a Systems)
F7AZ- 19589- DA (Motorcraft YN-
12- C) WSH-
M1C231-
B Klj . 1 ba
32003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Horn
Refer to Wiring Diagrams Cell
44 , Horns/Cigar Lighter for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the horn (13832).
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If fault is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 413-
06: Horn 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051
Visual Inspection Chart Mechanical Electrical
z
Damaged horns
z Damaged horn switch
z Damaged air bag sliding contact
(14A664) z
Blown battery junction box (BJB) Fuse Horn
Relay (20A)
z Damaged wiring harness
z Damaged connections
z Damaged horn relay
z Damaged horn switch
Symptom Chart Condition
Possible Sources Action
z The horn does not
sound z
BJB Fuse Horn Relay (20A).
z Circuitry.
z Horn relay.
z Air bag sliding contact.
z Horn switch.
z Horns. z
GO to
Pinpoint Test A .
z The horn sounds
continuously z
Circuitry.
z Horn relay.
z Remote entry system (generic
electronic module [GEM]) z
GO to
Pinpoint Test B . Klj . 1 ba
52003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST A: THE HORN DOES NOT SOUND module.
z Horn switch. Test Step Result / Action to
Take A1 CHECK POWER SUPPLY TO HORN RELAY
z
Disconnect: Horn Relay.
z Measure the voltage between the horn relay connector Pin 2,
Circuit 460 (YE/LB), harness side and ground; and between the
horn relay connector Pin 5, Circuit 460 (YE/LB), harness side and
ground.
z Are the voltages greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. A2 CHECK HORN RELAY
z
Check the horn relay; refer to Wiring Diagrams Cell 149.
z Is the horn relay OK? Yes
GO to
A3 .
No
INSTALL a new horn
relay. TEST the
system for normal
operation. A3 CHECK HORN SWITCH SIGNAL TO HORN RELAY
z
Measure the resistance between horn relay connector Pin 1,
Circuit 6 (YE/LG), harness side and ground under the following
conditions:
Horn Switch Position Horn Switch Position Resistance
Pressed Less than 5 ohms
Released Greater than 10,000 ohms Yes
GO to
A4 .
No
GO to A5 . Klj . 2 ba
52003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
202003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
142003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

LOW
PINPOINT TEST B: THE CHARGING SYSTEM WARNING INDICATOR
IS ON WITH THE ENGINE RUNNING (THE BATTERY VOLTAGE
DOES NOT INCREASE)
Test Step Result / Action to Take
A1 CHECK BATTERY CONDITION
z
Carry out the Battery— Condition Test to determine if
the battery can hold a charge and is OK for use.
Refer to Section 414 - 01 .
z Is the battery OK? Yes
GO to
A2 .
No
INSTALL a new battery. REFER
to Section 414 - 01 . TEST the
system for normal operation. A2 CHECK THE GENERATOR OUTPUT
z
Carry out the On- Vehicle Generator Load/No Load
Test. Refer to Component Tests in this section.
z Is the generator OK? Yes
GO to
A3 .
No
GO to Pinpoint Test B .
A3 CHECK FOR CURRENT DRAINS
z
Carry out the Battery— Drain Test. Refer to
Component Tests in this section.
z Are there any excessive current drains? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
A4 .
A4 CHECK FOR CURRENT DRAINS WHICH SHUT OFF
WHEN THE BATTERY IS DISCONNECTED z
Carry out the Battery— Electronic Drains Which Shut
Off When the Battery Cable is Disconnected Test.
Refer to Component Tests in this section.
z Are there any current drains which shut off when
the battery is disconnected? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
Pinpoint Test B .
Test Step Result / Action to
Take B1 CHECK GENERATOR B+ CIRCUIT 38 (BK/OG)
z
Disconnect: Generator B+ C102b.
z Measure the voltage between the generator C102b, circuit 38
(BK/OG), component side and ground. Yes
GO to
B2 .
No
REPAIR the circuit.
TEST the system for
normal operation. Klj . 5 ba
142003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST O: THE FOG LAMPS ARE INOPERATIVE Condition
Possible Sources Action
z The fog lamps are
inoperative z
BJB Fuse 27 (20A).
z CJB Fuse 38 (20A).
z Circuitry.
z Fog lamp relay.
z Fog lamp interrupt
relay.
z Headlamp switch.
z Fog lamp switch.
z Multifunction switch. z
GO to Pinpoint Test O .
z The individual fog lamp is
inoperative z
Fog lamp bulb.
z Circuitry. z
GO to Pinpoint Test P .
z The fog lamps are on
continuously z
Fog lamp relay.
z Circuitry.
z Fog lamp switch. z
GO to Pinpoint Test Q .
Test Step Result / Action
to Take O1 CHECK THE PARK LAMPS
z
Place the headlamp switch in the PARK position.
z Place the multifunction switch in low beam position.
z Do the park lamps illuminate? Yes
Turn off the
headlamp switch.
GO to
O2 .
No
GO to Pinpoint Test L .
O2 CHECK THE FOG LAMP RELAYS
z
Disconnect: Fog Lamp Relay.
z Disconnect: Fog Lamp Interrupt Relay.
z Check the fog lamp relay and fog lamp interrupt relay; refer to Wiring
Diagrams Cell 149.
z Are the relays OK? Yes
GO to
O3 .
No
INSTALL new
relay(s). TEST
the system for
normal
operation. O3 CHECK THE CIRCUIT 12 (LG/BK)
z
Measure the voltage between fog lamp interrupt relay connector Pin 1,
Circuit 12 (LG/BK), harness side and ground. Yes
GO to
O4 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 2 ba
62003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

(LB/OG) FOR SHORT TO GROUND BETWEEN THE GEM AND
THE MULTIFUNCTION SWITCH
z
Key in OFF position.
z Using the following table, measure the resistance between
the GEM C201e Pins, harness side and ground.
z Are the resistances greater than 10,000 ohms? Pin Circuit
5 682 (DB)
18 684 (PK/YE)
19 680 (LB/OG) Yes
REPAIR the circuit(s) in
question. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B9 .
B9 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680
(LB/OG) FOR AN OPEN CONDITION BETWEEN GEM AND
MULTIFUNCTION SWITCH z
Using the following table, measure the resistance between
the GEM C201e Pins, harness side and multifunction
switch C202a Pins, harness side.
z Are the resistances less than 5 ohms? GEM Multifunction Switch Circuit
C260 Pin 5 C202a Pin 685 682 (DB)
C260 Pin 18 C202a Pin 590 684 (PK/YE)
C260 Pin 19 C202a Pin 993 680 (LB/OG) Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 - 10 .
REPEAT the self- test.
CLEAR the DTCs.
No
REPAIR circuit(s) in question.
REPEAT the self- test.
CLEAR the DTCs. B10 CHECK CIRCUITS 65 (DG) FOR OPEN CIRCUIT
CONDITION BETWEEN BJB AND CJB NOTE:
Verify voltage at CJB F26 (30A) before carrying out
this test.
z Disconnect: Wiper On/Off Relay.
z Measure the voltage between BJB ON and OFF wiper Yes
GO to
B11 .
No Klj . 9 ba
202003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...