test G FORD MUSTANG 2003 Workshop Manual

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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Pinpoint Tests
PINPOINT TEST P1464: DTC P1464: A/C DEMAND OUT OF SELF-
TEST RANGE high speed
motor switch resistor.
z Damaged heater blower
motor switch. Test H .
z No operation in high
blower setting z
Circuitry short/open.
z Damaged heater blower
motor switch. z
Go To Pinpoint
Test I .
z No operation in lower
speeds z
Circuitry short/open.
z Damaged heater blower
motor switch resistor.
z Damaged heater blower
motor switch. z
Go To Pinpoint
Test J .
Test Step Result / Action to Take
P14641 RECHECK FOR THE DTC
z
Key in ON position.
z Make sure the function selector switch is in the OFF
position.
z Enter the following diagnostic mode on the diagnostic
tool: PCM Self- Test.
z Is DTC P1464 retrieved? Yes
GO to
P14642 .
No
The system is functioning
correctly. This DTC will set if the
A/C is turned on when carrying
out the PCM self- test. P14642 CHECK PID ACCS WITH THE A/C CONTROL
DISCONNECTED z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: PCM PID ACCS.
z Does PID ACCS read ON? Yes
GO to
P14643 .
No
INSTALL a new function selector
switch. REFER to Section 412 -
04 . REPEAT the PCM self-test
and verify DTC P1464 is no
longer retrieved. P14643 CHECK CIRCUIT 348 (VT) FOR A SHORT TO B+
z
Key in OFF position.
z Disconnect: PCM C175.
z Key in ON position.
z Measure the voltage at the function selector switch
C294c- 4, circuit 348 (VT), the harness side and ground. Yes
REPAIR circuit 348 (VT ) for a
short to B+. REPEAT the PCM
self-
test and verify DTC P1464 is
no longer retrieved.
No
INSTALL a new powertrain
control module. REFER to
Section 303 - 14 . REPEAT the
PCM self- test and verify DTC
P1464 is no longer retrieved. Klj . 7 ba
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PINPOINT TEST A: INCORRECT/ERRATIC DIRECTION OF AIRFLOW
FROM OUTLET z
Is there voltage present? Test Step Result / Action to
Take A1 CHECK AIRFLOW FROM DEFROSTER OUTLETS
z
Key in START position.
z Place the heater blower motor switch in the HI position and
rotate the function selector switch to each position.
z Check for correct airflow from each function selector switch
position at engine idle and during engine speed acceleration.
z Is there airflow from defroster outlets under all conditions? Yes
GO to
A2 .
No
If the airflow is from
defroster outlets in all
switch positions only
under engine speed
acceleration, GO to
A19 .
If the airflow is
incorrect under one or
more conditions, GO to
A13 .
If the airflow is correct
under all conditions,
RETURN to the
Symptom Chart. A2 CHECK THE VACUUM SUPPLY HOSE
z
Key in OFF position.
z Verify the vacuum supply hose is connected between the engine
manifold and the A/C vacuum check valve.
z Is the hose connected? Yes
GO to
A3 .
No
RECONNECT the
hose. TEST the system
for normal operation. A3 LEAK CHECK THE VACUUM SUPPLY HOSE Klj . 8 ba
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z
Disconnect: Vacuum Supply Hose.
z Connect one end of the vacuum supply hose to a vacuum pump
and test for leaks.
z Does the hose leak? Yes
REPAIR or INSTALL a
new vacuum hose.
TEST the system for
normal operation.
No
GO to
A4 .
A4 CHECK THE VACUUM CHECK VALVE
z
Key in START position.
z Check the A/C vacuum check valve for correct installation by
removing (one at a time) the reservoir hose and the control
assembly source hose from the A/C vacuum check valve. Check
for vacuum.
z Is vacuum available at both check valve ports? Yes
GO to
A6 .
No
GO to A5 .
A5 INSPECT THE VACUUM CHECK VALVE
z
Key in OFF position.
z Disconnect: A/C Vacuum Check Valve.
z Inspect the A/C vacuum check valve for an obstruction and
correct operation. Airflow through the A/C vacuum check valve
should be in the direction toward the engine (engine connection
site is marked "VAC").
z Is the A/C vacuum check valve plugged or obstructed? Yes
INSTALL a new A/C
vacuum check valve.
TEST the system for
normal operation.
No
GO to
A6 .
A6 LEAK TEST THE VACUUM CHECK VALVE
z
Key in OFF position.
z Disconnect: Vacuum Check Valve.
z Connect the A/C vacuum check valve to a vacuum pump with
two hoses and a tee fitting. Yes
INSTALL a new A/C
vacuum check valve.
TEST the system for
normal operation.
No
RECONNECT the A/C
vacuum check valve.
GO to
A7 . Klj . 9 ba
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z
Pump 51 kPa (15 in- Hg) vacuum on the A/C vacuum check valve
and observe the gauge reading.
z If the vacuum loss exceeds 3.37 kPa (1 in- Hg) per minute,
remove the A/C vacuum check valve from the tester and plug the
vacuum hoses. Pump 51 kPa (15 in- Hg) of vacuum with the
tester to be certain the hoses and tester are not the cause of the
leak.
z Does the A/C vacuum check valve lose more than 3.37 kPa
(1 in- Hg) of vacuum in one minute? A7 CHECK THE VACUUM RESERVOIR
z
Disconnect: A/C Vacuum Reservoir Tank.
z Use a vacuum pump to leak test the A/C vacuum reservoir tank.
z Does the reservoir leak? Yes
INSTALL a new A/C
vacuum reservoir tank.
TEST the system for
normal operation.
No
RECONNECT the A/C
vacuum reservoir tank.
GO to
A8 .
A8 CHECK THE SUPPLY HOSE
z
Disconnect: Function Selector Switch Supply Hose.
z Use a vacuum pump to leak test the function selector switch
supply hose.
z Does the function selector switch supply hose leak? Yes
REPAIR or INSTALL a
new function selector
switch supply hose.
TEST the system for
normal operation.
No
RECONNECT the
function selector switch
supply hose. GO to
A9
.
A9 CHECK THE CONTROL ASSEMBLY
z
Disconnect: In- line Vacuum Harness.
z Connect a vacuum pump to the black hose and plug the other
hoses. Yes
NOTE the function
selector switch position
where the vacuum
drops. GO to
A10 . Klj . 10 ba
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z
At each function selector switch position, apply 51 kPa (15 in- Hg)
of vacuum and check for vacuum drop.
z Does the vacuum drop exceed 3.37 kPa (1 in- Hg) per
minute? No
RECONNECT the in-
line vacuum harness
connector. GO to
A11 .
A10 LEAK TEST THE CONTROL ASSEMBLY
z
Disconnect: Function Selector Switch Vacuum.
z Connect a vacuum pump to the function selector switch supply
port and plug the control port that indicated a leak in Step A9.
z Select the function selector switch position that indicated a leak
in Step A9 and then apply 51 kPa (15 in- Hg) of vacuum.
z Does the vacuum drop exceed 1.68 kPa (0.5 in- Hg) per
minute? Yes
INSTALL a new
function selector
switch. TEST the
system for normal
operation.
No
RECONNECT the
function selector switch
vacuum connector. GO
to
A12 .
A11 CHECK THE SUPPLY HOSE FOR OBSTRUCTIONS
z
Disconnect: Mode Selector Switch Supply Hose.
z Connect a vacuum pump to the supply hose and try to pull a
vacuum. If the vacuum pump can pull a vacuum, the hose is
plugged. If the vacuum pump pulls a partial vacuum, the hose is
restricted.
z Is the hose plugged or restricted? Yes
INSTALL a new supply
hose. TEST the system
for normal operation.
No
RECONNECT the A/C
damper door switch
supply hose. GO to
A15
.
A12 LEAK TEST THE JUMPER VACUUM HARNESS
z
Disconnect:
z Disconnect the suspect hose.
z Plug one end of the suspect hose and attach a vacuum pump to
the other end. Apply 51 kPa (15 in- Hg) of vacuum to the hose. Yes
REPAIR or INSTALL a
new vacuum jumper
harness. TEST the Klj . 11 ba
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z
Does the vacuum drop? system for normal
operation.
No
REPAIR or INSTALL a
new function selector
switch. TEST the
system for normal
operation.
A13 REVIEW THE VEHICLE'S HISTORY
z
Key in OFF position.
z Review the vehicles history.
z Did the climate control system function correctly prior to
this concern? Yes
GO to
A16 .
No
GO to A14 .
A14 CHECK THE VACUUM HOSES TO DAMPER DOORS
z
Connect a vacuum pump to each hose and try to pull a vacuum.
If the vacuum pump can pull a vacuum, the hose is plugged. If
the vacuum pump pulls a partial vacuum, the hose is restricted.
z Is a hose plugged or restricted? Yes
INSTALL a new
vacuum hose. TEST
the system for normal
operation.
No
GO to
A15 .
A15 CHECK THE VACUUM HARNESS
z
Compare the vacuum hose color in each vacuum harness to the
vacuum diagram.
z Does the hose color agree with the schematics? Yes
GO to
A16 .
No
INSTALL a new
vacuum harness. TEST
the system for normal
operation. A16 CHECK A/C VACUUM CIRCUIT
z
Check the A/C vacuum circuit for pinched or kinked vacuum
hose. Yes
REPAIR or INSTALL a
new vacuum hose.
TEST the system for
normal operation.
No
GO to
A17 . Klj . 12 ba
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z
Is the hose pinched or kinked? A17 CHECK VACUUM CIRCUIT CONNECTIONS
z
Check each vacuum hose connection to determine if it is partially
connected or disconnected.
z Is a vacuum hose disconnected or partially connected? Yes
RECONNECT the
hose. TEST the system
for normal operation.
No
GO to
A18 .
A18 CHECK THE VACUUM HOSE
z
Disconnect the suspect hose.
z Plug one end of the hose and attach a vacuum pump to the other
end. Check for a leak in the hose.
z Does the vacuum hose leak? Yes
REPAIR or INSTALL a
new hose. TEST the
system for normal
operation.
No
GO to
A19 .
A19 CHECK THE VACUUM CONTROL MOTOR
z
Disconnect: Vacuum Control Motor.
z Check the vacuum control motor for leaks with a vacuum pump. Yes
GO to
A20 .
No
INSTALL a new
vacuum control motor.
TEST the system for
normal operation. Klj . 13 ba
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PINPOINT TEST B: INSUFFICIENT, ERRATIC, OR NO HEAT z
Does the vacuum control motor hold a vacuum? A20 CHECK THE VACUUM CONTROL MOTOR INSTALLATION
z
Key in OFF position.
z Check the attachment of the vacuum control motor arm to
damper door.
z Is the vacuum control motor arm attached to the door or
door crank arm? Yes
REPAIR or INSTALL a
new damper door.
TEST the system for
normal operation.
No
CONNECT the vacuum
control motor arm to
the door and check
operation. TEST the
system for normal
operation.
Test Step Result / Action to Take
B1 CHECK FOR CORRECT ENGINE COOLANT LEVEL
z
Key in OFF position.
z Check the engine coolant level when hot and cold.
z Is the engine coolant at the correct level (hot/cold) as
indicated on the engine coolant recovery reservoir? Yes
GO to
B2 .
No
GO to B3 .
B2 CHECK FOR HOT WATER TO THE HEATER CORE INLET
HOSE WARNING: The heater core inlet hose will become
too hot to handle and may cause serious burns if the
system is working correctly.
z Key in START position.
z Allow the engine to reach normal operating temperature.
z Feel the heater core inlet hose. Yes
GO to
B4 .
No
TEST the engine cooling
system for correct
operation. REFER to
Section 303 - 03A or
Section 303 - 03B . Klj . 14 ba
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PINPOINT TEST C: THE A/C DOES NOT OPERATE/DOES NOT
OPERATE CORRECTLY z
Is the heater core inlet hose too hot to handle? B3 CHECK THE ENGINE COOLING SYSTEM INCLUDING
RADIATOR CAP FOR LEAKS z
Fill the engine cooling system to specified level.
z NOTE: It is not necessary to check the components
separately at this time.
z Pressure check the engine cooling system. Refer to Section 303 - 03A or
Section 303 - 03B .
z Does the engine cooling system, including the radiator
cap, hold pressure? Yes
GO to
B4 .
No
Pressure test the heater
core. REFER to
Component Tests, Heater
Core — Pressure Test. B4 CHECK THE HEATER CORE OUTLET HOSE FOR HOT
WATER z
Feel the heater core outlet hose.
z Is the heater core outlet hose cool or cold? Yes
TEST the heater core for a
plugged or partially
plugged condition. REFER
to
Section 303 - 03A or
Section 303 - 03B .
No
GO to Pinpoint Test E .
Test Step Result / Action to Take
C1 CHECK THE PCM PID WACF
z
Connect the diagnostic tool.
z Turn the function selector to the OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool:
z Monitor the PCM PID WACF while turning the function
selector.
z Does the PCM PID WACF read YES? Yes
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
C2 .
C2 CHECK THE PCM PID WACF WITH THE A/C ON
z
Turn the function selector switch to the A/C position.
z Enter the following diagnostic mode on the diagnostic Yes
REFER to the Powertrain Klj . 15 ba
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