AC system FORD MUSTANG 2003 Workshop Manual

z
Is any voltage present? B6 CHECK THE FUEL PUMP ASSEMBLY FEED CIRCUIT 29
(YE/WH) z
Key in OFF position.
z Measure the resistances between the instrument cluster C220b
pin 19, circuit 29 (YE/WH), harness side and the fuel pump
module C463 pin 5, circuit 29 (YE/WH), harness side; and
between the instrument cluster C220b pin 19, circuit 29 (YE/WH),
harness side and ground.
z Is the resistance less than 5 ohms between the instrument
cluster and the fuel pump module and greater than 10,000
ohms between the instrument cluster and ground? Yes
GO to
B7 .
No
REPAIR the circuit.
TEST the system for
normal operation. B7 CHECK FUEL PUMP MODULE GROUND CIRCUIT 327 (BK/OG)
AND CIRCUIT 397 (BK/WH) z
Measure the resistance between the instrument cluster C220b
pin 20, circuit 397 (BK/WH), harness side and the fuel pump
module C463 pin 8, circuit 327 (BK/OG), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B8 .
No
REPAIR the circuit(s)
in question. TEST the
system for normal
operation. B8 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure they
seat correctly. Yes
INSTALL a new
instrument cluster.
REFER to
Instrument Cluster in this section.
TEST the system for Klj . 17 ba
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PINPOINT TEST C: INCORRECT OIL PRESSURE GAUGE
INDICATION z
Operate the system and verify the concern is still present.
z Is the concern still present? normal operation.
No
The system is
operating correctly at
this time. Concern may
have been caused by
a loose or corroded
connector. CLEAR the
DTCs. REPEAT the
self-
test. Test Step Result / Action to
Take C1 CHECK THE INSTRUMENT CLUSTER OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Instrument Cluster Active Command.
z Trigger the instrument cluster active command OIL GAUGE.
Scroll to 0%, 50%, and 100%.
z Did the gauge display L at 0%, the middle of the gauge at
50%, and H at 100%? Yes
GO to
C2 .
No
GO to C3 .
C2 CHECK CIRCUIT 31 (WH/RD) FOR OPEN OR SHORT TO
GROUND z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Disconnect: Oil Pressure Switch C103.
z Measure the resistances between the instrument cluster C220b
pin 16, circuit 31 (WH/RD), harness side and the oil pressure
switch C103, circuit 31 (WH/RD), harness side; and between the
instrument cluster C220b pin 16, circuit 31 (WH/RD), harness
side and ground.
z Is the resistance less than 5 ohms between the instrument
cluster and the oil pressure switch, and greater than 10,000
ohms between the instrument cluster and ground? Yes
INSTALL a new oil
pressure switch. TEST
the system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
C3 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
z
Disconnect all instrument cluster connectors. Yes
INSTALL a new Klj . 18 ba
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PINPOINT TEST D: INCORRECT TEMPERATURE GAUGE
INDICATION
PINPOINT TEST E: INCORRECT VOLTAGE GAUGE INDICATION—
EXCEPT COBRA z
Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure they
seat correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? instrument cluster.
REFER to
Instrument Cluster in this section.
TEST the system for
normal operation.
No
The system is
operating correctly at
this time. Concern may
have been caused by a
loose or corroded
connector. CLEAR the
DTCs. REPEAT the
self- test. Test Step Result / Action to Take
D1 CARRY OUT THE INSTRUMENT CLUSTER
ENGINE COOLANT TEMPERATURE GAUGE
ACTIVE COMMAND z
Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the
diagnostic tool: Instrument Cluster Active
Command.
z Trigger instrument cluster active command
ENGCOOLNT. Monitor the engine coolant
temperature gauge while adjusting the
ENGCOOLNT active command to read 50%
and 100%.
z Does the temperature gauge start at cold,
move to half at 50%, and full hot at 100%? Yes
REFER to the Powertrain
Control/Emissions Diagnosis (PC/ED)
manual.
No
GO to
D2 .
D2 CHECK FOR CORRECT INSTRUMENT
CLUSTER OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and
make sure they seat correctly.
z Operate the system and verify the concern is
still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster.
REFER to
Instrument Cluster in this
section. TEST the system for normal
operation.
No
The system is operating correctly at this
time. Concern may have been caused by
a loose or corroded connector. CLEAR the
DTCs. REPEAT the self-test. Test Step Result / Action to
Take E1 CHECK THE INSTRUMENT CLUSTER Klj . 19 ba
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CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Instrument Cluster Active Command.
z Trigger the instrument cluster voltage gauge active command.
Scroll to 0%, 50%, and 100%.
z Did the voltage gauge indicate L at 0%, the middle of the
gauge at 50%, and H at 100%? Yes
GO to
E2 .
No
GO to E4 .
E2 CHECK CHARGING SYSTEM
z
Check the charging system operation. REFER to Section 414 -
00 .
z Is the charging system operating correctly? Yes
GO to
E3 .
No
REPAIR the charging
system as needed.
REFER to Section 414 -
00 .
E3 CHECK CIRCUIT 904 (LG/RD) FOR OPEN OR SHORT TO
GROUND z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Disconnect: Generator C102a.
z Measure resistance between the generator C102a pin 1, circuit
904 (LG/RD), harness side and the instrument cluster C220a pin
5, circuit 904 (LG/RD), harness side; and between the generator
C102a pin 1, circuit 904 (LG/RD), harness side and ground.
z Is the resistance less than 5 ohms between the generator
and the instrument cluster; and greater than 10,000 ohms
between the generator and ground? Yes
The system is operating
correctly at this time.
No
REPAIR the circuit.
TEST the system for
normal operation.
E4 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure they
seat correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new
instrument cluster.
REFER to
Instrument Cluster in this section.
TEST the system for
normal operation.
No
The system is operating
correctly at this time.
Concern may have
been caused by a loose
or corroded connector.
CLEAR the DTCs. Klj . 20 ba
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PINPOINT TEST F: INCORRECT TACHOMETER INDICATION
PINPOINT TEST G: INCORRECT BOOST GAUGE INDICATION—
COBRA ONLY REPEAT the self-
test. Test Step Result / Action to Take
F1 CHECK THE TACHOMETER
OPERATION z
Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on
the diagnostic tool: Instrument Cluster
Active Command.
z Trigger the instrument cluster active
command TCHOMETER. Scroll to 0%,
50%, and 100%.
z Did the tachometer display read 0 at
0%, half the tachometer display at
50%, and the full tachometer display
at 100%? Yes
REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual.
No
GO to
F2 .
F2 CHECK FOR CORRECT INSTRUMENT
CLUSTER OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they seat
correctly.
z Operate the system and verify the
concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the
system for normal operation.
No
The system is operating correctly at this time.
Concern may have been caused by a loose or
corroded connector. CLEAR the DTCs.
REPEAT the self- test. Test Step Result / Action to Take
G1 CHECK BOOST GAUGE
PRESSURE LINE z
Disconnect the boost gauge
pressure line from the intake
manifold.
z Apply 69 kPa (10 psi) to the boost
gauge pressure line.
z Does the boost gauge indicate
maximum boost pressure? Yes
CHECK for a plugged manifold fitting. TEST the
system for normal operation.
No
GO to
G2 .
G2 CHECK THE BOOST GAUGE
z
Disconnect the boost gauge
pressure line from the instrument
cluster.
z Apply 10 psi to the boost gauge.
z Does the boost gauge indicate
maximum boost pressure? Yes
INSTALL a new boost gauge pressure line. TEST the
system for normal operation.
No
INSTALL a new instrument cluster. REFER to Klj . 21 ba
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PINPOINT TEST H: THE LOW FUEL WARNING INDICATOR IS
NEVER/ALWAYS ON
PINPOINT TEST I: THE SPEEDOMETER IS INOPERATIVE Instrument Cluster in this section. TEST the system
for normal operation. Test Step Result / Action to Take
H1 CARRY OUT THE INSTRUMENT CLUSTER
WARNING LAMPS AND CHIME ACTIVE
COMMAND USING THE DIAGNOSTIC TOOL z
Key in OFF position.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the
diagnostic tool: Instrument Cluster Active
Command.
z Select the instrument cluster WARNING
LAMPS AND CHIME active command. Trigger
the ALL LAMPS active command. Observe the
LOW FUEL warning indicator.
z Is the LOW FUEL warning indicator
illuminating? Yes
GO to
H2 .
No
GO to H3 .
H2 THE LOW FUEL GAUGE WARNING
INDICATOR IS NEVER/ALWAYS ON z
Check the fuel gauge for correct operation.
z Is the fuel gauge operating correctly? Yes
GO to
H3 .
No
Go To Pinpoint Test B .
H3 CHECK FOR CORRECT INSTRUMENT
CLUSTER OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and
make sure they seat correctly.
z Operate the system and verify the concern is
still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster.
REFER to
Instrument Cluster in this
section. TEST the system for normal
operation.
No
The system is operating correctly at this
time. Concern may have been caused by
a loose or corroded connector. CLEAR
the DTCs. REPEAT the self-test. Test Step Result / Action to Take
I1 TEST THE INSTRUMENT
CLUSTER z
Carry out the instrument cluster
self- diagnostic mode.
z Did the gauge sweep? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No Klj . 22 ba
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PINPOINT TEST J: THE ODOMETER IS INOPERATIVE
PINPOINT TEST K: THE SAFETY BELT INDICATOR IS INOPERATIVE
(CHIME IS OPERATIVE)/DOES NOT OPERATE CORRECTLY GO to
I2 .
I2 CHECK FOR CORRECT
INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they
seat correctly.
z Operate the system and verify
the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the system for
normal operation.
No
The system is operating correctly at this time. Concern
may have been caused by a loose or corroded
connector. CLEAR the DTCs. REPEAT the self- test. Test Step Result / Action to Take
J1 CHECK THE ODOMETER
DISPLAY z
Key in ON position.
z Is the odometer displaying all
dashes? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
J2 .
J2 CHECK FOR CORRECT
INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they
seat correctly.
z Operate the system and verify
the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the system for
normal operation.
No
The system is operating correctly at this time. Concern
may have been caused by a loose or corroded
connector. CLEAR the DTCs. REPEAT the self- test. Test Step Result / Action to Take
K1 CHECK IF THE GEM IS RECEIVING THE CORRECT
IGNITION SWITCH STATUS CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Connect the diagnostic tool. Yes
GO to
K2 .
No
REFER to Section 211 - 05 . Klj . 23 ba
412003 Mustang Workshop Manual
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z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Generic Electronic Module (GEM) PID.
z Monitor the GEM PIDs IGN_KEY, IGN_S, IGN_R, and
IGN_A, while inserting the ignition key and cycling the
ignition switch through all the positions.
z Did the PIDs agree with the ignition switch positions? K2 CHECK IF THE GEM IS RECEIVING THE CORRECT
SAFETY BELT SWITCH STATUS z
Monitor GEM PID D_SBELT while buckling and unbuckling
the driver safety belt.
z Did the PID display IN with the safety belt buckled and
OUT with the safety belt unbuckled? Yes
GO to
K3 .
No
REFER to Section 413 - 09 .
K3 CHECK THE GEM FOR INTERNAL OPEN OR SHORT
z
Key in OFF position.
z Monitor the safety belt warning indicator when turning the
ignition from the OFF to the ON position.
z Key in ON position.
z Did the safety belt warning indicator illuminate for
approximately three seconds and turn off? Yes
GO to
K10 .
No
GO to K4 .
K4 DETERMINE IF SAFETY BELT INDICATOR CIRCUIT IS
SHORTED TO GROUND z
Buckle the driver safety belt.
z Is the safety belt indicator always on? Yes
GO to
K5 .
No
GO to K7 .
K5 CHECK IF THE GEM IS INTERNALLY GROUNDED
z
Key in OFF position.
z Disconnect: GEM C201e.
z Key in ON position.
z Observe the safety belt warning indicator.
z Is the safety belt warning indicator always on? Yes
GO to
K6 .
No
GO to K10 .
K6 CHECK CIRCUIT 450 (DG/LG) FOR A SHORT TO GROUND
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance between the GEM C201e pin 26,
circuit 450 (DG/LG), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
K11 .
No
REPAIR the circuit. TEST
the system for normal
operation. K7 CHECK CIRCUIT 450 (DG/LG) FOR A SHORT TO
BATTERY z
Key in OFF position.
z Disconnect: GEM C201e.
z Disconnect: Instrument Cluster C220a. Yes
REPAIR the circuit. TEST
the system for normal Klj . 24 ba
412003 Mustang Workshop Manual
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z
Measure the voltage between the GEM C201e pin 26,
circuit 450 (DG/LG), harness side and ground.
z Is any voltage present? operation.
No
GO to
K8 .
K8 CHECK THE GEM MODULE FOR AN INTERNAL OPEN
z
Connect: Instrument Cluster C220a.
z Install a fused (10A) jumper wire between the GEM C201e
pin 26, circuit 450 (DG/LG), harness side and ground.
z Key in ON position.
z Did the safety belt indicator illuminate? Yes
GO to
K10 .
No
GO to K9 .
K9 CHECK CIRCUIT 450 (DG/LG) FOR AN OPEN
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance between the GEM C201e pin 26,
circuit 450 (DG/LG), harness side and instrument cluster
C220a pin 4, circuit 450 (DG/LG), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
K11 .
No
REPAIR the circuit. TEST
the system for normal
operation. K10 CHECK FOR CORRECT GEM OPERATION
z
Disconnect all GEM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all GEM connectors and make sure they seat
correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
TEST the system for normal
operation.
No
The system is operating
correctly at this time. Klj . 25 ba
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PINPOINT TEST L: INACCURATE SPEEDOMETER READING
PINPOINT TEST M: THE O/D OFF INDICATOR IS NEVER ON Concern may have been
caused by a loose or
corroded connector. CLEAR
the DTCs. REPEAT the self-
test.
K11 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure
they seat correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
No
The system is operating
correctly at this time.
Concern may have been
caused by a loose or
corroded connector. CLEAR
the DTCs. REPEAT the self-
test. Test Step Result / Action to Take
L1 CHECK SPEEDOMETER OPERATION
z
Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on
the diagnostic tool: Instument Cluster
Active Command.
z Trigger the instrument cluster active
command SPDOMETER. Scroll to 0%,
50%, and 100%.
z Did the speedometer display read 0 at
0%, half the speedometer display at
50%, and the full speedometer display
at 100%? Yes
REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual.
No
GO to
L2 .
L2 CHECK FOR CORRECT INSTRUMENT
CLUSTER OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they seat
correctly.
z Operate the system and verify the
concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the
system for normal operation.
No
The system is operating correctly at this time.
Concern may have been caused by a loose or
corroded connector. CLEAR the DTCs.
REPEAT the self- test. Klj . 26 ba
412003 Mustang Workshop Manual
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