2003 FORD MUSTANG test G

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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...