engine FORD MUSTANG 2003 Workshop Manual

tool:
z Monitor the PCM PID WACF while turning the function
selector.
z Does the PCM PID WACF read YES? Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
C3 .
C3 CHECK THE PCM PID ACCS WITH THE A/C ON
z
Key in START position.
z Make sure the engine is at idle.
z Enter the following diagnostic mode on the diagnostic
tool: PCM PID ACCS.
z Monitor the PCM PID ACCS while turning the function
selector.
z Does the PCM PID ACCS read ON? Yes
GO to
C4 .
No
GO to C6 .
C4 CHECK PCM PID WAC WITH THE A/C ON
NOTE:
When PCM PID WACF is YES, this is the same
fault as DTC P1460.
z Enter the following diagnostic mode on the diagnostic
tool: PCM PID WAC.
z Monitor the PCM PID WAC while turning the function
selector.
z Does the PCM PID WAC read ON? Yes
GO to
C20 .
No
GO to C5 .
C5 CHECK THE INPUT SIGNAL TO THE PCM
z
Key in OFF position.
z Disconnect: PCM C175.
z Key in ON position.
z Measure the voltage at PCM C175- 41, circuit 198
(DG/OG), harness side and ground.
z Is the voltage reading greater than 10 volts? Yes
INSTALL a new powertrain
control module. TEST the
system for normal operation.
No
GO to
C6 .
C6 CHECK THE REFRIGERANT PRESSURE
z
Key in OFF position.
z Connect the manifold gauge set. Refer to Refrigerant System Tests in this section.
z Is the system pressure 345- 1,724kPa (50-250psi)? Yes
GO to
C7 .
No
REPAIR the leaks and
RETEST the system for normal
operation. REFER to Section 412 - 03 .
C7 CHECK THE SUPPLY TO THE FUNCTION SELECTOR
SWITCH z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Key in ON position.
z Measure the voltage at the function selector switch
C294c- 2, circuit 883 (PK/LB), harness side and ground. Yes
GO to
C17 .
No
GO to C8 . Klj . 16 ba
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z
Turn the function selector switch to each of the following
positions and note the resistance reading:
zMAX A/C
z A/C
z VENT
z FLOOR
z MIX
z DEFROST
z Are any of the readings less than 10,000 ohms? C11 CHECK CIRCUIT C198 (DG/OG) FOR A SHORT TO
GROUND z
Connect: A/C Cycling Switch C130.
z Disconnect: A/C Pressure Cut-off Switch C1078.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between the A/C pressure cut-
off switch C1078- 3, circuit 198 (DG/OG), harness side
and ground.
z Is the resistance reading less than 10,000 ohms? Yes
GO to
C14 .
No
GO to C12 .
C12 CHECK THE A/C CYCLING SWITCH FOR A SHORT
TO GROUND z
Disconnect: A/C Cycling Switch C130.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between the A/C pressure cut-
off switch C1078- 2, circuit 420 (DB/YE), harness side
and ground. Yes
REPAIR circuit C420 (DB/YE)
for a short to ground. TEST for
normal operation.
No
INSTALL a new A/C cycling
switch. REFER to
Section 412 -
03 . TEST system for normal
operation. Klj . 18 ba
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z
Is the voltage reading greater than 10 volts? C16 MEASURE THE RESISTANCE OF CIRCUIT 348 (VT)
z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Measure the resistance between the A/C function
selector switch C294c- 1, circuit 348 (VT), harness side
and A/C cycling switch C130- 4, circuit 348 (VT), harness
side.
z Is the resistance reading less than 5 ohms? Yes
INSTALL a new function
selector switch. REFER to
Section 412
- 04 . TEST the
system for normal operation.
No
REPAIR circuit 348 (VT) for an
open. TEST the system for
normal operation. C17 MEASURE THE VOLTAGE TO THE A/C PRESSURE
CUT- OFF SWITCH z
Key in OFF position.
z Connect: A/C Cycling Switch C130.
z Disconnect: A/C Pressure Cut-off Switch C1078.
z Turn the function selector switch to the A/C position.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the voltage at the A/C high pressure cut- off
switch C1078- 2 circuit 420 (DB/YE), harness side and
ground. Yes
GO to
C19 .
No
GO to C18 . Klj . 20 ba
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z
Is the voltage reading greater than 10 volts? C18 CHECK THE A/C CYCLING SWITCH
z
Key in OFF position.
z Disconnect: A/C Cycling Switch C130.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between A/C cycling switch
C130- 2, circuit 420 (DB/YE), harness side and the A/C
high pressure cut- off switch C1078-2, circuit 420
(DB/YE), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new A/C cycling
switch. REFER to
Section 412 -
03 . TEST the system for
normal operation.
No
REPAIR circuit 420 (DB/YE) for
an open. TEST the system for
normal operation. C19 CHECK THE A/C PRESSURE CUT-
OFF SWITCH z
Key in OFF position.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between Rotunda Breakout Box
pin 41 and A/C high pressure cut- off switch C1078-3,
circuit 198 (DG/OG), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new A/C pressure
cut-
off switch. REFER to
Section 412 - 03 . TEST the
system for normal operation.
No
REPAIR circuit 198 (DG/OG)
for an open. TEST the system
for normal operation. C20 CHECK THE GROUND CIRCUIT AT THE CONSTANT
CONTROL RELAY MODULE z
Key in OFF position. Yes Klj . 21 ba
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to plot a vertical line for ambient temperature and a
horizontal line for A/C clutch OFF time in seconds.
z Is the intersection of the two lines above the upper
limit? DISCHARGE and RECOVER
the system to remove
excessive moisture or
refrigerant oil. REFER to
Air Conditioning (A/C) System
Recovery, Evacuation and
Charging . TEST the system
for normal operation.
No
GO to E7 .
E6 CHECK FOR A HIGH SUCTION PRESSURE
z
Refer to the data plot used to evaluate the system low
pressure performance in Step E3.
z Is the intersection of the two lines above the upper
limit? Yes
REMOVE the A/C evaporator
core orifice to repair missing or
damaged (leaking) O-
ring
seals. REFER to Section 412 -
03 . TEST the system for
normal operation.
No
INSTALL a new A/C cycling
switch when the intersection of
the two lines is below the
lower limit. REFER to Section 412 - 03 . TEST the system for
normal operation. E7 CHECK THE AMBIENT TEMPERATURE
z
Refer to the data plot used to evaluate the system A/C
clutch OFF time in Step E5.
z Is the ambient temperature above 26°C (80°F)? Yes
This is normal operation for
the refrigerant system in high
humidity conditions.
No
DISCHARGE and RECOVER
the system to correct an
overcharge condition. REFER
to
Air Conditioning (A/C) System Recovery, Evacuation
and Charging . TEST the
system for normal operation. E8 CHECK FOR A HIGH DISCHARGE PRESSURE
z
Refer to the data plot used to evaluate the system high
pressure performance in Step E2.
z Is the intersection of the two lines above the upper
limit? Yes
GO to
E9 .
No
GO to E11 .
E9 CHECK FOR A NORMAL LOW PRESSURE
z
Use the recorded data from the refrigerant system tests
to plot a vertical line for ambient temperature and a
horizontal line for compressor suction (low) pressure. Yes
REFER to
Section 303 - 03A or
Section 303 - 03B . to diagnose
the engine cooling system.
TEST the system for normal
operation. Klj . 27 ba
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PINPOINT TEST F: NO OPERATION IN ALL TEMPERATURE
SETTINGS
PINPOINT TEST G: THE BLOWER MOTOR DOES NOT
OPERATE/DOES NOT OPERATE CORRECTLY INSTALL a new A/C
compressor due to low
performance. REFER to
Section 412
- 03 . TEST the
system for normal operation. Test Step Result / Action to Take
F1 CHECK THE TEMPERATURE CONTROL
z
Start the engine and run at idle. Allow the engine to reach
normal operating temperature.
z Place the function selector switch in the NORMAL A/C
position.
z Adjust the temperature control to full warm position, and
physically feel the discharge air temperature at the at the
center panel vents.
z Rotate the temperature control to full cold position, and
physically feel the discharge air temperature at the center
panel vents.
z Does the discharge air temperature vary? Yes
The temperature blend
door is functioning
correctly. RETURN to the
symptom chart.
No
GO to
F2 .
F2 CHECK FOR A BROKEN A/C TEMPERATURE CONTROL
CABLE z
Remove the climate control assembly to gain access to the
control cable head.
z Move the temperature control from full warm to full cold.
z Inspect the cable control head as you move the temperature
control.
z Does the alignment mark on the control head move? Yes
INSTALL a new
evaporator housing.
REFER to
Section 412 -
02 .
No
INSTALL a new
temperature control cable
assembly. REFER to
Section 412 - 04 .
Test Step Result / Action to Take
G1 CHECK FOR VOLTAGE AT C238
z
Disconnect: Blower Motor Jumper C238.
z Key in ON position.
z Turn the blower motor selector to LOW.
z Turn the function selector to FLOOR.
z Check for voltage between C238- 6, circuit 249 (DB/LG) and
C238- 3, circuit 261 (OG/BK). Yes
GO to
G2 .
No
GO to G4 . Klj . 30 ba
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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
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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
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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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GENERAL PROCEDURES
Refrigerant System Tests
1. Connect the R- 134a Manifold Gauge Set. For additional information, refer to Manifold Gauge Set Connection in this section.
2. Adjust the climate controls for maximum cooling. zStart the engine.
z Select MAX A/C operation.
z Set the blower motor speed to maximum.
3. Stabilize the in- vehicle temperature at 21- 27°C (70-80°F).
4. NOTE: When the ambient temperatures exceed 38°C (100°F), do not run the engine above
normal idle speed.
Maintain the engine speed at 1,500 rpm.
5. Determine the compressor discharge (high) pressure. 1. Record the ambient temperature.
2. Record the discharge (high) pressure.
3.NOTE: In ambient temperatures between 38- 43°C (100-110°F), the system performance
pressures will be the same as those for ambient temperatures shown on the chart in the
32- 38°C (90- 100°F) range.
The system performance is acceptable when the pressure reading falls between the
upper and lower limits shown.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
R-
134a Manifold Gauge Set
176- R032A or equivalent Klj . 1 ba
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