2003 FORD MUSTANG engine coolant

Heater Core
WARNING: Carbon monoxide gas is colorless, odorless and dangerous. If it is necessary
to operate the engine with the vehicle in a closed area such as a garage, always use an exhaust
collector to vent the exhaust gases outside the closed area. Failure to follow these instructions
may result in personal injury.
1. NOTE: Testing of returned heater cores reveals that a large percentage of heater cores are
good and did not require installation of a new heater core. If a heater core leak is suspected, the
heater core must be tested by following the Plugged Heater Core Component Test before the
Heater Core Pressure Test. Carry out a system inspection by checking the heater system
thoroughly as follows:
Inspect for evidence of coolant leakage at the heater water hose to heater core attachments. A
coolant leak in the heater water hose could follow the heater core tube to the heater core and
appear as a leak in the heater core.
CAUTION: Spring- type clamps are installed as original equipment. Installation and
overtightening of non- specification clamps can cause leakage at the heater water hose
connection and damage the heater core.
2. Check the integrity of the heater water hose clamps.
Heater Core— Plugged
WARNING: The heater core inlet hose will become too hot to handle if the system is
working correctly.
1. Check to see that the engine coolant is at the correct level.
2. Start the engine and turn on the heater.
3. When the engine coolant reaches operating temperature, feel the heater core outlet hose to see if it is hot.
If it is not hot:
zthe heater core may have an air pocket.
z the heater core may be plugged.
z the thermostat is not working correctly.
Heater Core— Pressure Test
Use the radiator/heater core pressure tester to carry out the pressure test. 1. NOTE: Due to space limitations, a bench test may be necessary for pressure testing.
Drain the coolant from the cooling system. For additional information, refer to Section 303 - 03A
or
Section 303 - 03B .
2. Disconnect the heater water hoses from the heater core. For additional information, refer to Klj . 37 ba
412003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

GENERAL PROCEDURES
Air Conditioning (A/C) System Check —
Retail Procedure
NOTE: This Retail Procedure is not eligible for claiming on Ford paid repairs (warranty and ESP).
NOTE: The engine should be run at idle for 10 minutes with the air conditioning on and set to MAX A/C
before carrying out this retail procedure.
NOTE: Read and follow all of the Warnings, Cautions and Notes at the beginning of this section before
continuing.
1. Visual inspection
Open the hood and visually inspect the heating and air conditioning systems for the following:
zCoolant reservoir for correct coolant level
z Heater hoses for deterioration or loose connections
z Radiator and condenser for debris or damaged fins restricting airflow, loose mounting or
connections
z Accessory drive belt(s) and cooling fan(s) for wear or physical damage
z Refrigerant lines and connections for physical damage or loose connections
z Compressor for physical damage or loose connections
z Suction accumulator/drier for physical damage or loose connections
z Wiring and connectors for excessive wear, loose or damaged connections, or incorrect
routing
2. A/C refrigerant analysis
zCarry out air conditioning refrigerant analysis. For additional information, refer to
Refrigerant Identification Testing in this section.
z If the refrigerant fails the analysis, discontinue diagnosis and make recommendations for
repairs.
z If the refrigerant passes the analysis, carry out the air conditioning system check.
3. Air conditioning system check
zConnect manifold gauge set or charging station with gauges to refrigerant system.
z With the vehicle in park, parking brake set, thermometer installed in center panel vent,
and air conditioning system on and set to MAX A/C, start the engine.
z Record air refrigerant system pressures while running the engine at 1,500 rpm and allow
engine to return to idle.
z Operate the blower motor in all control positions and check for correct blower speed
changes.
z With the blower motor on HI, operate air discharge mode selector in all positions and
check for correct airflow in each position.
z Operate the temperature blend selector in all positions and check for correct change in
discharge temperature. Check the air discharge temperature with the selector in the
coolest position and the air conditioning on and set to MAX A/C to determine if the air
discharge temperature is acceptable for the current ambient air temperature.
z Carry out the EATC self- test (if applicable).
If the refrigerant system pressures were low, carry out the refrigerant system leak test.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Klj . 1 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

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
32003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

DESCRIPTION AND OPERATION
Heating and Defrosting
The heating and defrosting system has the following features:
zControls the temperature and, during A/C operation, reduces the relative humidity of the air
inside the vehicle.
z Delivers heated or cooled air to maintain the vehicle interior temperature and comfort level.
z Controls the A/C blower motor speed.
z Cooling or heating can be adjusted to maintain the desired temperature.
z System uses a reheat method to provide conditioned air to the passenger compartment.
z The blower motor (19805) draws outside air through the air inlet duct from just below the
windshield during all system operations except for MAX A/C cooling (when recirculated air is
used).
z All airflow from the blower motor passes through the A/C evaporator core (19860).
z The temperature is then regulated by reheating a portion of the air and blending it with the
remaining cool air to the desired temperature.
z The temperature blending is varied by the air temperature control door, which regulates the
amount of air that flows through and around the heater core (18476), where it is then mixed and
distributed.
Heater Core
The heater core (18476) consists of fins and tubes arranged to extract heat from the engine coolant
and transfer it to air passing through the heater core. Blower Motor SECTION 412-
02: Heating and Ventilation 2003 Mustang Workshop Manual Klj . 1 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

SPECIFICATIONS
SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual General Specifications
Item Specification
Lubricant
PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-
DA (MC YN-12-
C) WSH-
M1C231-
B
Torque Specifications Description Nm lb-
ft lb-
in A/C compressor mounting bolts 25 18 —
A/C manifold retaining bolt 20 15 —
3.8L engine A/C compressor mounting bracket bolts 47 35 —
3.8L engine A/C compressor mounting bracket nut 25 18 —
A/C compressor clutch retaining bolt 13 10 —
Suction accumulator/drier clamp screw 8 — 71
Coolant bottle bolts 10 — 89
Peanut fittings 8 — 71
Radiator bracket bolts 9 — 81
Condenser core bracket bolts 5 — 44
A/C muffler bracket nut 25 18 — Klj . 1 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

DESCRIPTION AND OPERATION
Instrument Cluster
The instrument cluster (10849) consists of the following components:
Instrument Cluster—
Base 3.8L Engine
SECTION 413-
01: Instrument Cluster 2003 Mustang Workshop Manual 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
14 — Traction control indicator
15 — Overdrive off (O/D OFF) indicator (automatic Klj . 1 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~ ...