vacuum FORD MUSTANG 2003 Workshop Manual

System Air Flow Description
MAX A/C
When MAX A/C is selected:
zThe air inlet door vacuum control motor is at full vacuum, closing off outside air and admitting
only recirculated air.
z The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum
control motor is at no vacuum, directing airflow to the instrument panel A/C registers. A small
amount of airflow from the side window demisters will be present.
z Blended air temperature is available.
z The A/C compressor will operate if the outside temperature is above approximately 6°C (43°F).
z The blower motor is on.
NORM A/C
When NORM A/C is selected:
zThe air inlet door vacuum control motor is at no vacuum, admitting only outside air into the
passenger compartment. 9 19D990 A/C evaporator core orifice
10 19860 A/C evaporator core
11 — Low pressure vapor
12 — High pressure vapor
13 — Low pressure liquid
14 — High pressure liquid Klj . 6 ba
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z
The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum
control motor is at no vacuum, directing airflow to the instrument panel A/C registers. A small
amount of airflow from the side window demisters will be present.
z Blended air temperature is available.
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.
PANEL
When PANEL is selected:
zThe air inlet door vacuum control motor is at no vacuum, admitting only outside air into the
passenger compartment.
z The panel/defrost door vacuum control motor is at full vacuum and the panel/floor door vacuum
control motor is at no vacuum, directing airflow to the instrument panel A/C registers. A small
amount of airflow from the side window demisters will be present.
z The temperature can be adjusted to heat the air, but the air cannot be cooled below the outside
temperature.
z The A/C compressor will not operate.
z The blower motor is on.
OFF
When OFF is selected:
zThe air inlet door vacuum control motor is at full vacuum, closing off outside air from entering
the passenger compartment.
z The panel/floor door vacuum control motor is at full vacuum and the panel/defrost door vacuum Klj . 7 ba
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control motor is at no vacuum, closing off airflow to the defrost duct, side window demisters,
floor duct and instrument panel A/C registers.
z The A/C compressor will not operate.
z The blower motor is off.
FLOOR
When FLOOR 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 vacuum control motor is at full vacuum and the panel/defrost door vacuum
control motor is at no vacuum, directing airflow to the floor duct. A small amount of airflow from
the side window demisters will be present.
z The temperature can be adjusted to heat the air, but the air cannot be cooled below the outside
temperature.
z The A/C compressor will not operate.
z The blower motor is on.
FLOOR/DEFROST
When FLOOR/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 vacuum control motor is at partial vacuum and the panel/defrost door
vacuum control motor is at no vacuum, directing airflow to the floor duct, the defroster duct, and
the side window demisters.
z The temperature can be adjusted to heat or cool the air below the outside temperature. Klj . 8 ba
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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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DIAGNOSIS AND TESTING
Climate Control System
Refer to Wiring Diagrams Cell
54 , Air Conditioner/Heater for schematic and connector information.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Connector, Refrigerant
Pressure Line
412-
093 (T94P-19623- E) Set, A/C Fittings
412-
DS028 (014- 00333, D93L-
19703- B) or equivalent Vacuum Pump Kit
416-
D002 (D95L-7559- A) or
equivalent Breakout Box, EEC-V Control
System
418- 049 (014-00950, T94L-50-
EEC- V) Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Pressure Test Kit
014-
R1072 or equivalent 77 III Automotive Meter
105-
R0056 or equivalent Klj . 1 ba
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Vacuum Schematic — Manual Climate Control System R-
134a Manifold Gauge Set
176- R032A or equivalent Refrigerant Leak Detector
216-
00001 or equivalent Klj . 2 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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Function Selector Switch Vacuum Connector
V=Vacuum
NV=No Vacuum
Inspection and Verification
1. Verify the customer's concern by operating the climate control system to duplicate the condition. 16 18476 Heater core
17 18A559 Panel/floor door (full vacuum position)
18 — Floor airflow
19 18A318 Vacuum control motor—
floor/panel door 20 — Panel vent airflow
Port No. Hose Color Function
1 White Air inlet door
2 Red Panel/floor door
3 Blue Panel/floor door
4 Yellow Panel/defrost door
5 Black Vacuum source
6 — Not used
Function Selector Switch Vacuum Application Chart Switch Port Color Function Function Selector Switch Position
MAX A/C A/C Vent OFF Floor FLR/ DEF Defrost
1 White Recirc/Fresh V NV NV V NV NV NV
2 Red Floor NV NV NV V V NV NV
3 Blue Panel/floor NV NV NV V V V NV
4 Yellow Panel/defrost V V V NV NV NV NV
5 Black Vacuum source V V V V V V V Klj . 4 ba
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2. Inspect to determine if one of the following mechanical or electrical concerns apply:
a A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times
(large leak), or only when specific functions are selected (indicating a leak in that portion of the
circuit). The vacuum hoses used in the passenger compartment control circuit are constructed
from PVC plastic material. The vacuum hoses used in the engine compartment are constructed
of Hytrel® . Because of the materials used, never pinch the vacuum hoses off during diagnosis
to locate a leak. A wood golf tee can be used as a plug when it is necessary to plug one end of
a vacuum hose for leak test purposes.
3. If the inspection reveals obvious concerns that can be readily identified, repair as required.
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 vehicle selection cannot be entered:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
If the scan tool still does not allow the vehicle selection to be entered, refer to the scan tool manual. 5. Carry out the DATA LINK DIAGNOSTIC TEST using the scan tool. If the scan tool responds with:
zCKT 914, CKT 915 or CKT 70 = ALL MODULE NO RESPONSE/NOT EQUIPPED, go to
Communication System Diagnostics in Section 418 - 00 to diagnose network concern.
z If the powertrain control module (PCM) is not listed for a communication concern, turn
the A/C function selector switch to OFF and execute self- test diagnostics for the PCM.
6. If any PCM DTCs are retrieved, and are related to the concern, go to the Powertrain Control Module Diagnostic Trouble Code (DTC) Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, go to the Symptom Chart to continue diagnostics.
Symptom Chart Visual Inspection Chart Mechanical Electrical
z
Loose, missing or damaged A/C compressor
drive belt.
z Loose or disconnected A/C clutch.
z Loose, misrouted or damaged vacuum lines. a
z Broken or leaking refrigerant lines.
z Broken or leaking vacuum control motor. z
Open fuses.
z Blower motor inoperative.
z A/C compressor inoperative.
z Circuitry open/shorted.
z Disconnected electrical
connectors.
Powertrain Control Module Diagnostic Trouble Code (DTC) Index DTC Description Action
P1460 WOT A/C cutout circuit
malfunction Refer to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
P1464 A/C demand out of self-
test
range GO to DTC P1464. Klj . 5 ba
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Symptom Chart
Condition
Possible Sources Action
z Incorrect/erratic direction
of airflow from outlet(s) z
No vacuum to A/C heater
function switch selector.
z A/C heater function selector
switch leaks vacuum.
z Kinked/pinched vacuum hose.
z Leaking vacuum control
motor.
z Leaking A/C vacuum check
valve.
z Leaking A/C vacuum reservoir
tank and bracket.
z Vacuum actuator arm not
connected to door crank. z
Go To Pinpoint
Test A .
z Insufficient, erratic, or no
heat z
Low engine coolant level.
z Thermostat stuck open.
z Disengaged/damaged
temperature cable. z
Go To Pinpoint
Test B .
z The A/C does not
operate/does not operate
correctly z
CASS strategy failure.
z Open fuses.
z A/C clutch relay.
z Shorted blend door actuator.
z Powertrain control module.
z Circuitry short/open.
z A/C cycling switch damaged.
z A/C system discharged/low
charge.
z Function selector switch
damaged.
z A/C pressure cut-off switch
damaged.
z A/C compressor clutch
damaged. z
Go To Pinpoint
Test C .
z The A/C is always on zCircuitry short/open.
z A/C cycling switch.
z A/C heater function selector
switch.
z Constant control relay
module.
z Incorrect A/C clutch air gap. z
Go To Pinpoint
Test D .
z Insufficient A/C cooling zRestricted A/C evaporator
core orifice.
z Low refrigerant level. z
Go To Pinpoint
Test E .
z No operation in all the
temperature settings z
Damaged blend door actuator
cable.
z Damaged air temperature
control door. z
Go To Pinpoint
Test F .
z The blower motor does
not operate z
Open fuse.
z Circuitry open/shorted.
z Damaged heater blower
motor switch (18578).
z Damaged heater blower
motor switch resistor (18591).
z Damaged blower motor relay.
z Damaged blower motor. z
Go To Pinpoint
Test G .
z The blower motor
operates continuously in z
Circuitry short/open.
z Damaged heater blower z
Go To Pinpoint Klj . 6 ba
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