2003 FORD MUSTANG window

z
The A/C compressor will operate if the outside air temperature is above approximately 6°C (43°
F).
z The blower motor is on.
DEFROST
When DEFROST is selected:
zThe air inlet door vacuum control motor is at no vacuum, admitting only outside air into the
passenger compartment.
z The panel/floor door and panel/defrost door vacuum control motors are at no vacuum, directing
airflow to the defroster duct and the side window demisters.
z The temperature can be adjusted to heat or cool the air below the outside temperature.
z The A/C compressor will operate if the outside air temperature is above approximately 6°C (43°
F).
z The blower motor is on. Electrical Components Klj . 9 ba
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Item Part Number Description
1 18A318 Vacuum control motor, panel/defrost door
2 18A478 Panel/defrost door (full vacuum position)
3 — Defrost airflow
4 — Side window demister airflow
5 18B545 Temperature blend door (full heat position)
6 19860 A/C evaporator core
7 19A813 Air inlet door (full vacuum position)
8 — Outside air inlet
9 18A318 Vacuum control motor—
air inlet door 10 — Recirculated air inlet
11 19805 Blower motor
12 — Vacuum from the engine intake manifold
13 19A563 A/C vacuum check valve
14 19A566 A/C vacuum reservoir tank and bracket
15 19B888 A/C-
heater function selector switch Klj . 3 ba
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GENERAL PROCEDURES
Heater Hose Coupling
Disconnect
CAUTION: Do not attempt to install a new bushing, spacer or O- rings in the heater hose
coupling; damage to the heater hose coupling can result. If the heater hose coupling is the
cause of a coolant leak, the affected heater hose must be replaced as an assembly.
1. WARNING: The engine must be off, fully cool and the cooling system fully
depressurized before attempting to disconnect any heater water hoses. Failure to comply
with this warning can result in serious injury or burns from hot liquid escaping out of the
engine cooling system.
Depressurize the engine cooling system.
2. Push the heater hose toward the tube to fully expose the locking tabs.
3. NOTE: When compressing the white coupling retainer with the special tool, the special tool
must be perpendicular to and on the highest point of the coupling.
NOTE: If the heater hose coupling is accessible, the retainer tabs can be compressed by hand
to disconnect the heater hose.
Push the special tool over the coupling retainer windows to compress the retainer locking tabs.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Remover, Heater Hose Inlet
Tube
412-
042 (T85T-18539- AH) Disconnect Tool, Heater Hose
412-
127
Material Item Specification
MERPOL®
—
ESE-
M99B144- B Klj . 1 ba
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DESCRIPTION AND OPERATION
Air Distribution
NOTE:
The air distribution system of this vehicle cannot be equipped with a cabin air filter.
There are two sources of air available to the air distribution system:
zoutside air
z recirculated air
Recirculated air is only used during MAX A/C.
Air distribution within the vehicle is determined by the function selector switch position. Airflow control
doors are used to direct airflow within the air plenum chamber. Vacuum control motors (18A318) are
used to position these airflow control doors. Refer to Section 412 - 00 for a description and operation of
each of the system functions.
The air distribution system is designed to provide airflow from the defrost nozzle when no vacuum is
applied to any of the vacuum control motors. This is done to prevent a situation where defrost cannot
be obtained due to a system vacuum leak.
Air enters the passenger compartment from the:
zinstrument panel A/C register (19893).
z heater outlet floor duct (18C433).
z windshield defroster hose nozzle (18490).
z side window demisters.
Passenger compartment air is exhausted from the vehicle through open windows or body air vents.
Instrument Panel Registers
There are A/C registers on the left and right sides of the instrument panel and in the center instrument
panel finish panel.
The LH and RH A/C registers are only serviceable as assemblies.
The center A/C registers are not serviceable as assemblies. The registers are installed with the
instrument panel center finish panel assembly. Component Locations SECTION 412-
01: Air Distribution and Filtering 2003 Mustang Workshop Manual Klj . 1 ba
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DESCRIPTION AND OPERATION
Instrument Cluster and Panel Illumination
The instrument cluster and panel illumination system illuminates the following components:
zinstrument cluster (10849)
z audio unit (18806)
z A/C- heater control
z fog lamp switch
z transmission range indicator
z traction control switch
z rear window defrost control switch
The instrument cluster is a hybrid electronic cluster (HEC), which uses both hardwired circuitry and the
standard corporate protocol (SCP) communication network to transmit and receive information. The
Mustang instrument cluster backlighting has illumination bulbs that are installed separately from the
instrument cluster. The Cobra instrument cluster has a laminated, electroluminescent applique to
backlight the cluster . The electroluminescent applique and instrument cluster must be installed as an
assembly. SECTION 413-
00: Instrument Cluster and Panel Illumination 2003 Mustang Workshop Manual Klj . 1 ba
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GEM Diagnostic Trouble Code (DTC) Index
DTC Description Source Action
B1218 Horn Relay Coil Circuit Short to
VBatt GEM REFER to
Section 501 - 14B .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
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 .
B1339 Chime Input Request Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU is Defective GEM Clear the DTCs. Retrieve the DTCs. If DTC B1342
is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
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 .
B1408 Driver Power Window Up
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM Go To Pinpoint Test K .
B1428 Lamp Safety Belt Circuit Failure GEM Go To Pinpoint Test K .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay Coil
Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay Coil
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 . Klj . 8 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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B1408 Driver Power Window Up
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1410 Driver Power Window Motor
Circuit Failure GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit
Short to Battery GEM REFER to
Section 413 - 01 .
B1428 Lamp Safety Belt Circuit
Failure GEM REFER to
Section 413 - 01 .
B1431 Wiper Brake/Run Relay
Circuit Failure GEM REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay
Coil Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay
Coil Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 .
B1446 Wiper Park Sense Circuit
Failure GEM REFER to
Section 501 - 16 .
B1448 Wiper Park Sense Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1450 Wiper Wash/Delay Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1453 Wiper Wash/Delay Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 .
B1458 Wiper Washer Pump Motor
Relay Circuit Failure GEM REFER to
Section 501 - 16 .
B1460 Wiper Washer Pump Motor
Relay Coil Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1462 Safety Belt Switch Circuit
Failure GEM REFER to
Section 413 - 09 .
B1466 Wiper Hi/Low Speed Not
Switching GEM REFER to
Section 501 - 16 .
B1473 Wiper Low Speed Circuit
Motor Failure GEM REFER to
Section 501 - 16 .
B1476 Wiper High Speed Circuit
Motor Failure GEM REFER to
Section 501 - 16 .
B1551 Decklid Release Circuit
Failure GEM REFER to
Section 501 - 14B .
B1553 Decklid Release Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1555 Ignition Run/Start Circuit
Failure GEM REFER to
Section 211 - 05 .
B1687 Lamp Dome Input Circuit
Short to Battery GEM REFER to
Section 417 - 02 .
B2486 LF Side Repeater Lamp GEM REFER to
Section 417 - 01 . Klj . 4 ba
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