2003 FORD MUSTANG service

The fitting is an integral part of the refrigeration line or component.
zSpecial couplings are required for both the high side and low side service gauge ports.
z A new Schrader- type valve core can be installed if the seal leaks.
z Always install the A/C charging valve cap (19D702) on the service gauge port valves after
repairing the refrigerant system. 19D734)
6 19D702 A/C charging valve cap Klj . 10 ba
102003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

REMOVAL AND INSTALLATION
Evaporator Core
Removal and Installation
NOTE:
The evaporator core is not separately serviceable, it is serviced only with the evaporator core
housing assembly.
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.
NOTE: If an evaporator core leak is suspected, the evaporator core must be leak tested before it is
removed from the vehicle. For additional information, refer to Section 412 - 00 .
1. Remove the evaporator core housing. For additional information, refer to Section 412 - 02 .
2. Transfer the components from the old evaporator core housing to the new evaporator core housing.
3. Install the evaporator core housing. For additional information, refer to Section 412 - 02 .
SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual Klj . 1 ba
12003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

COOL (blue) to WARM (red) causes a corresponding movement on the air temperature control
door and determines the temperature that the system will maintain.
z The A/C heater function selector switch combines a vacuum selector valve for direct control of
the vacuum control motors and electrical input to the instrument control module.
Control System Outputs
Blower Motor Switch Resistor
The heater blower motor switch resistor has the following features:
zThe assembly is located on the passenger side of the plenum assembly behind the glove
compartment (06010).
z Three resistance elements are mounted on the resistor board to provide four A/C blower motor
speeds.
z Depending on the heater blower motor switch position, series resistance is added or bypassed
in the A/C blower motor circuit to decrease or increase A/C blower motor speed.
z An overheating protective device (thermal limiter) will open the resistor coil circuit when the
temperature reaches 105°- 110°C (221°-230°F), interrupting the blower motor operation in all
speeds except HI.
z The thermal limiter cannot be reset and is not serviceable.
Control Actuators
Temperature Control Cable
The temperature control cable (19988) has the following features:
zThe cable assembly has a constant tension (pull- pull) dual cable design.
z The pull- pull design allows for constant smooth communication between the temperature control
knob and the air temperature blend door.
z The control cable can only be installed as an assembly.
Vacuum Control Motors
The vacuum control motors (18A318) control the position of the doors directing the air flow to the
different outlets. There are two types of vacuum control motors used in this system:
zSingle- diaphragm for air inlet and windshield defroster door operations.
z Double- diaphragm for air damper door operations.
Single- diaphragm motors have two positions:
z Shaft extended with no vacuum applied.
z Shaft retracted with vacuum applied.
Double- diaphragm motors have three positions:
z Shaft extended with no vacuum applied to either port.
z Shaft halfway retracted with vacuum applied to only one port. Klj . 3 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Instrument Cluster—
Base 4.6L Engine transmission)
16 — LOW FUEL level indicator
17 — SERVICE ENGINE SOON indicator
18 — THEFT indicator
19 — AIR BAG warning indicator
20 — Charging system indicator
21 — Safety belt warning indicator
Item Part
Number Description
1 — Fuel gauge
2 — Engine coolant temperature gauge
3 — Speedometer
4 — Turn signal/hazard indicator
5 — High beam indicator
6 — Tachometer
7 — Odometer
8 — Trip odometer reset button
9 — Voltmeter gauge
10 — Oil pressure gauge
11 — CHECK FUEL CAP indicator
12 — BRAKE warning indicator
13 — ABS warning indicator Klj . 2 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Instrument Cluster—
Cobra 14 — Traction control indicator
15 — Overdrive off (O/D OFF) indicator (automatic
transmission)
16 — LOW FUEL level indicator
17 — SERVICE ENGINE SOON indicator
18 — THEFT indicator
19 — AIR BAG warning indicator
20 — Charging system indicator
21 — Safety belt warning indicator
Item Part
Number Description
1 — Fuel gauge
2 — Engine coolant temperature gauge
3 — Speedometer
4 — Turn signal/hazard indicator
5 — High beam indicator
6 — Tachometer
7 — Odometer
8 — Trip odometer reset button
9 — Boost gauge
10 — Oil pressure gauge
11 — CHECK FUEL CAP indicator
12 — BRAKE warning indicator Klj . 3 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

13 — ABS warning indicator
14 — Traction control indicator
15 — Overdrive off (O/D OFF) indicator (automatic
transmission)
16 — LOW FUEL level indicator
17 — SERVICE ENGINE SOON indicator
18 — THEFT indicator
19 — AIR BAG warning indicator
20 — Charging system indicator
21 — Safety belt warning indicator Klj . 4 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
412003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE INSTRUMENT
CLUSTER z
The SERVICE ENGINE
SOON indicator is
never/always on z
Circuitry.
z SERVICE
ENGINE
SOON
indicator bulb.
z Powertrain
control module
(PCM).
z Instrument
cluster. z
Go To Pinpoint Test S .
z The turn/hazard
indicator is never/always
on z
Circuitry.
z Turn/hazard
bulb(s).
z Instrument
cluster. z
Go To Pinpoint Test T .
z The THEFT indicator is
never/always on z
Circuitry.
z THEFT
indicator LED.
z Instrument
cluster. z
REFER to Section 419 - 01 .
z The traction control
indicator is never/always
on z
Circuitry.
z Traction control
switch.
z Standard
corporate
protocol (SCP)
network.
z Powertrain
control module
(PCM).
z ABS module.
z Instrument
cluster. z
Go To Pinpoint Test U .
z The integrated circuit
display is
inoperative/erratic z
Instrument
cluster. z
Go To Pinpoint Test V .
z The instrument cluster is
inoperative z
Central junction
box (CJB) fuse
(s):
„11
(15A).
„ 21 (5A).
„ 34
(20A).
z Circuitry.
z Instrument
cluster. z
Go To Pinpoint Test V .
Test Step Result / Action to
Take Klj . 13 ba
412003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...