FORD MUSTANG 2003 Workshop Manual

No
GO to
O11 .
O4 DETERMINE IF GEM IS SENDING THE CORRECT OUTPUT
SIGNAL z
Trigger the GEM active command BKFLD LOW.
z Did the instrument cluster BRAKE warning indicator
illuminate? Yes
GO to
O14 .
No
GO to O9 .
O5 CHECK CIRCUIT BETWEEN THE PARKING BRAKE
SWITCH AND THE GEM FOR A SHORT TO GROUND z
Monitor PID PRK_BRK while applying and releasing the
parking brake.
z Did the PID read ON with the parking brake applied and
with the parking brake released? Yes
GO to
O8 .
No
GO to O6 .
O6 CHECK CIRCUIT 128 (VT/YE) AND CIRCUIT 22 (LB/BK)
FOR AN OPEN z
Key in OFF position.
z Disconnect: Parking Brake Switch C306.
z Disconnect: GEM C201d.
z Measure the resistance between the GEM C201d pin 4,
circuit 128 (VT/YE), harness side and the parking brake
switch C306 pin 1, circuit 22 (LB/BK), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
O7 .
No
REPAIR the circuit. TEST
the system for normal
operation. O7 CHECK CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between the parking brake switch
C306 pin 2, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new parking
brake switch. TEST the
system for normal
operation.
No
REPAIR the circuit. TEST
the system for normal
operation.
O8 CHECK CIRCUIT 128 (VT/YE) FOR A SHORT TO GROUND
z
Key in OFF position.
z Disconnect: Parking Brake Switch C306.
z Disconnect: GEM C201d.
z Measure the resistance between the GEM C201d pin 4,
circuit 128 (VT/YE), harness side and ground. Yes
REPAIR or INSTALL a new
parking brake switch as
needed. TEST the system
for normal operation. Klj . 29 ba
412003 Mustang Workshop Manual
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z
Is the resistance greater than 10,000 ohms? No
REPAIR the circuit. TEST
the system for normal
operation.
O9 CHECK CIRCUIT 128 (VT/YE) FOR SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201e.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the GEM C201e pin 13, circuit
128 (VT/YE), harness side and ground.
z Is any voltage indicated? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
GO to
O10 .
O10 CHECK CIRCUIT 128 (VT/YE) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between the GEM C201e pin 13,
circuit 128 (VT/YE), harness side and the instrument cluster
C220b pin 14, circuit 128 (VT/YE), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
O15 .
No
REPAIR the circuit. TEST
the system for normal
operation. O11 CHECK THE BRAKE FLUID LEVEL SWITCH FOR AN
INTERNAL GROUND z
Key in OFF position.
z Disconnect: Brake Fluid Level Switch C124.
z Key in ON position.
z With the parking brake released, observe the BRAKE
warning indicator.
z Is the BRAKE warning indicator always on? Yes
GO to
O12 .
No
INSTALL a new brake fluid
level switch. TEST the
system for normal
operation. Klj . 30 ba
412003 Mustang Workshop Manual
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O12 DETERMINE IF THE GEM IS INTERNALLY GROUNDED
z
Key in OFF position.
z Disconnect: GEM C201e.
z Key in ON position.
z Observe the BRAKE warning indicator.
z Is BRAKE warning indicator always on? Yes
GO to
O13 .
No
GO to O14 .
O13 CHECK CIRCUIT 128 (VT/YE) FOR SHORT TO GROUND
BETWEEN GEM AND INSTRUMENT CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure the resistance between the GEM C201e pin 13,
circuit 128 (VT/YE), harness side and ground.
z Is resistance greater than 10,000 ohms? Yes
GO to
O15 .
No
REPAIR the circuit. TEST
the system for normal
operation. O14 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.
Concern may have been
caused by a loose or
corroded connector. CLEAR
the DTCs. REPEAT the
self- test. O15 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 . 31 ba
412003 Mustang Workshop Manual
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PINPOINT TEST P: THE CHARGING SYSTEM WARNING INDICATOR
IS NEVER/ALWAYS ON
Test Step Result / Action to Take
P1 CHECK THE CHARGING SYSTEM
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Check the charging system operation. Refer to Section 414 -
00 .
z Is the charging system operating correctly? Yes
GO to
P2 .
No
REFER to Section 414 - 00 .
P2 CHECK CHARGING SYSTEM WARNING INDICATOR WITH
ENGINE OFF z
Key in ON position.
z Observe the charging system warning indicator.
z Is the charging system warning indicator on? Yes
GO to
P5 .
No
GO to P3 .
P3 CHECK THE INSTRUMENT CLUSTER INPUT
z
Key in OFF position.
z Disconnect: Generator C102c.
z Connect a fused (10A) jumper wire between the generator
C102c pin 1, circuit 904 (LG/RD), harness side and ground.
z Key in ON position.
z Does the charging system indicator illuminate? Yes
INSTALL a new generator.
REFER to
Section 414 - 02 .
TEST the system for normal
operation.
No
GO to P4 .
P4 CHECK CIRCUIT 904 (LG/RD) FOR OPEN
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a .
z Measure the resistance between the instrument cluster
C220a pin 5, circuit 904 (LG/RD), harness side and the
generator C102c pin 1, circuit 904 (LG/RD), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
P7 .
No
REPAIR the circuit. TEST
the system for normal
operation. P5 CHECK THE GENERATOR Klj . 32 ba
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PINPOINT TEST Q: THE HIGH BEAM INDICATOR IS
NEVER/ALWAYS ON z
Key in OFF position.
z Disconnect: Generator C102c.
z Key in ON position.
z Does the charging system indicator illuminate? Yes
GO to
P6 .
No
INSTALL a new generator.
REFER to Section 414 - 02 .
TEST the system for normal
operation. P6 CHECK CIRCUIT 904 (LG/RD) FOR SHORT TO GROUND
z
Key in OFF position.
z Measure the resistance between the generator C102c pin 1,
circuit 904 (LG/RD), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
P7 .
No
REPAIR the circuit. TEST
the system for normal
operation. P7 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
Q1 CHECK THE HIGH BEAM LAMP OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in ON position.
z Operate the high beams.
z Do the high beams operate correctly? Yes
GO to
Q2 .
No
REFER to Section 417 - 01 .
Q2 CHECK CIRCUIT 932 (GY/WH) AND CIRCUIT 12 (LG/BK)
FOR AN OPEN Klj . 33 ba
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PINPOINT TEST R: THE ABS WARNING INDICATOR IS NEVER ON z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the instrument cluster C220b
pin 2, circuit 12 (LG/BK), harness side and ground, while
turning the high beams on and off.
z Is the voltage 0 volts with the high beams off and
greater than 10 volts with the high beams on? Yes
GO to
Q3 .
No
REPAIR the circuit. TEST
the system for normal
operation. Q3 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
R1 CHECK THE ABS WARNING INDICATOR OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in ON position.
z Observe the ABS warning indicator. The ABS indicator
should prove out for approximately six seconds then turn off.
z Does the ABS warning indicator operate correctly? Yes
The system is operating
normally at this time.
No
If the indicator is
inoperative, GO to
R2 .
If the indicator is always
on, REFER to Section 206 -
09A or
Section 206 - 09B .
R2 CHECK THE INSTRUMENT CLUSTER INPUT
z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Connect a fused (10A) jumper wire between the anti- lock
brake control module C135 pin 16, circuit 603 (DG), harness Yes
REFER to
Section 206 - 09A
or
Section 206 - 09B . Klj . 34 ba
412003 Mustang Workshop Manual
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PINPOINT TEST S: THE SERVICE ENGINE SOON INDICATOR IS
NEVER/ALWAYS ON side and ground.
z Key in ON position.
z Does the ABS indicator illuminate? No
GO to
R3 .
R3 CHECK CIRCUIT 603 (DG) FOR AN OPEN
z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure the resistance between the instrument cluster
C220b pin 15, circuit 603 (DG), harness side and the anti-
lock brake control module C135 pin 16, circuit 603 (DG),
harness side.
z Is the resistance less than 5 ohms? Yes
GO to
R4 .
No
REPAIR the circuit. TEST
the system for normal
operation. R4 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
S1 CARRY OUT THE INSTRUMENT Klj . 35 ba
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PINPOINT TEST T: THE TURN/HAZARD INDICATOR IS
NEVER/ALWAYS ON CLUSTER SERVICE ENGINE SOON
INDICATOR 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 the instrument cluster active
command MIL.
z Did the SERVICE ENGINE SOON
indicator illuminate? Yes
REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual.
No
GO to
S2 .
S2 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 T1 CHECK THE TURN SIGNAL AND HAZARD LAMPS OPERATION
CAUTION: Use the correct probe adapter(s) when making
measurements. Failure to use the correct probe adapter(s) may
damage the connector.
z Key in ON position.
z Operate the left and right turn signals.
z Operate the hazard lamps.
z Do the turn signals and hazard lamps operate correctly? Yes
GO to
T2 .
No
REFER to Section 417 - 01 .
T2 CHECK THE CIRCUIT IN QUESTION —
CIRCUIT 2 (WH/LB) (RH)
OR CIRCUIT 3 (LG/WH) (LH) z
Key in OFF position.
z Disconnect: Instrument Cluster C220a (RH) or C220b (LH).
z Key in ON position.
z Measure the voltage between the instrument cluster C220a pin 3,
circuit 3 (LG/WH), harness side and ground, while the steering
column multifunction switch is placed in the left turn position (LH); or
between the instrument cluster C220b pin 3, circuit 2 (WH/LB),
harness side and ground, while the steering column multifunction
switch is placed in the right turn position (RH). Yes
GO to
T3 .
No
REPAIR the circuit
(s) in question.
TEST the system for
normal operation. Klj . 36 ba
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PINPOINT TEST U: THE TRACTION CONTROL INDICATOR IS
NEVER/ALWAYS ON z
Does the voltage alternate between 0 volts and 10 volts with
the turn signal on? T3 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
U1 DETERMINE IF THE TRACTION
CONTROL INDICATOR IS ALWAYS ON z
Observe the traction control indicator.
z Is the indicator always on? Yes
REFER to
Section 206 - 09B .
No Klj . 37 ba
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PINPOINT TEST V: THE INSTRUMENT CLUSTER IS INOPERATIVE GO to
U2 .
U2 DETERMINE IF INSTRUMENT
CLUSTER IS AT FAULT 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 TRAC OFF.
z Did the traction control indicator
illuminate? Yes
REFER to
Section 206 - 09B .
No
GO to U3 .
U3 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
V1 CHECK THE BATTERY POWER SUPPLY TO THE
INSTRUMENT CLUSTER CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure voltage between the instrument cluster C220b pin
10, circuit 729 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
V2 .
No
REPAIR the circuit. TEST
the system for normal
operation. V2 CHECK THE RUN POWER SUPPLY TO THE INSTRUMENT
CLUSTER z
Key in ON position.
z Measure the voltage between the instrument cluster C220b
pin 11, circuit 489 (PK/BK), harness side and ground. Yes
GO to
V3 . Klj . 38 ba
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