2003 FORD MUSTANG parking brake

The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
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3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible)
before proceeding to the next step.
4. If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the diagnostic tool still does not power up, refer to the diagnostic tool operating manual.
6. Carry out the DATA LINK DIAGNOSTICS test. If the diagnostic tool responds with: zCKT914, CKT915 OR CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for the instrument cluster, Go To Pinpoint Test A or for the
generic electronic module (GEM), Go To Pinpoint Test W .
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out the self- test diagnostics for the instrument
cluster or the GEM.
7. If the DTCs retrieved are related to the concern, go to the Instrument Cluster Diagnostic Trouble Code (DTC) Index or the GEM Diagnostic Trouble Code Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
Instrument Cluster Self- Diagnostic Mode
To enter the instrument cluster self- diagnostic mode, press and hold the instrument cluster
SELECT/RESET button, turn the ignition switch to the RUN position, and then continue pressing the
SELECT/RESET button (five seconds) until tESt is displayed in the odometer. The SELECT/RESET
button must be released within three seconds of the odometer tESt display to begin the self- diagnostic
mode. Press the SELECT/RESET button to advance through the following steps until dtc is displayed.
Depressing the SELECT/RESET button will display any stored continuous DTCs before proceeding to
the next step. z
Engine coolant level
z Accessory drive belt
z Engine oil level
z Parking brake position switch
z Brake fluid level
z Boost gauge pressure line „
5 (15A)
„ 7 (15A)
„ 11 (15A)
„ 13 (15A)
„ 21 (5A)
„ 23 (15A)
„ 24 (30A)
„ 29 (15A)
„ 30 (15A)
„ 32 (15A)
„ 34 (20A)
„ 35 (15A)
„ 37 (5A)
„ 38 (20A)
„ 39 (5A)
z Circuitry Klj . 5 ba
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z
Powertrain
control module
(PCM). manual.
z The CHECK FUEL CAP
INDICATOR is never on z
Circuitry.
z Standard
corporate
protocol (SCP)
network.
z Powertrain
control module
(PCM). z
Go To Pinpoint Test N .
z The CHECK FUEL CAP
INDICATOR is always
on z
Circuitry.
z Powertrain
control module
(PCM).
z Fuel system. z
REFER to the Powertrain
Control/Emissions
Diagnosis (PC/ED)
manual.
z The BRAKE warning
indicator is never/always
on z
Circuitry.
z Low brake fluid
level.
z Brake fluid
level switch.
z Parking brake
switch.
z Instrument
cluster.
z Generic
electronic
module (GEM). z
Go To Pinpoint Test O .
z The charging system
warning indicator is
never/always on z
Circuitry.
z Generator.
z Charging
system warning
indicator bulb.
z Instrument
cluster. z
Go To Pinpoint Test P .
z The high beam indicator
is never/always on z
Circuitry.
z High beam
indicator bulb.
z Instrument
cluster. z
Go To Pinpoint Test Q .
z The air bag warning
indicator is never/always
on z
Circuitry.
z Air bag warning
indicator bulb.
z Instrument
cluster.
z Restraint
control module
(RCM). z
REFER to Section 501 -
20B .
z The anti- lock brake
system (ABS) warning
indicator is never on z
Circuitry.
z ABS warning
indicator bulb.
z Anti- lock brake
control module.
z Instrument
cluster. z
Go To Pinpoint Test R .
z The ABS warning
indicator is always on z
Circuitry.
z Anti- lock brake
control module. z
REFER to Section 206 -
09A or
Section 206 - 09B . Klj . 12 ba
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PINPOINT TEST O: THE BRAKE WARNING INDICATOR IS
NEVER/ALWAYS ON INDICATOR LAMP CONTROL III ACTIVE
COMMAND USING THE DIAGNOSTIC TOOL
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the
diagnostic tool: Instrument Cluster Active
Command.
z Select the instrument cluster INDICATOR
LAMP CONTROL III active command.
Trigger the CHECK FUEL CAP active
command ON. Observe the CHECK FUEL
CAP indicator.
z Does the CHECK FUEL CAP indicator
illuminate? Yes
REFER to the Powertrain
Control/Emissions Diagnosis (PC/ED)
manual.
No
GO to
N3 .
N3 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
O1 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.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Generic Electronic Module (GEM) PID.
z Monitor GEM PIDs IGN_KEY, IGN_S, IGN_R, and IGN_A
while cycling the ignition switch through all positions and
then removing the key from ignition switch.
z Do the PIDs agree with the ignition switch status? Yes
GO to
O2 .
No
REFER to Section 211 - 05 .
O2 DETERMINE IF GEM IS RECEIVING THE CORRECT
PARKING BRAKE INPUT z
Monitor GEM PID PRK_BRK while applying and releasing
the parking brake.
z Did the PID read ON with the parking brake applied, and
OFF with the parking brake released? Yes
GO to
O3 .
No
GO to O5 .
O3 DETERMINE IF BRAKE WARNING INDICATOR CIRCUIT IS
OPEN OR GROUNDED z
Verify that the parking brake is released.
z Is the instrument cluster BRAKE warning indicator off? Yes
GO to
O4 . Klj . 28 ba
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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
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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
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GENERAL PROCEDURES
Belt Minder Deactivating/Activating
Preparation
1. Before deactivating/activating the belt minder, set the parking brake.
2. Place the gearshift in P (Park) (automatic transmission) or the neutral position (manual transmission).
3. Place the ignition switch in the OFF position.
4. Close all the vehicle doors.
5. Unbuckle the driver safety belt.
6. Place the parklamps/headlamps switch in the OFF position. (If the vehicle is equipped with Autolamps, this will not affect the procedure.)
Deactivating/Activating 1. Turn the ignition switch to the RUN position. (Do not start the engine.)
2. Wait until the safety belt warning lamp turns off. (approximately one to two minutes)
3. NOTE: Steps 3 through 5 must be completed within 60 seconds or the procedure must be
repeated.
Buckle then unbuckle the safety belt three times, ending with the safety belt unbuckled. This
portion of the procedure can be done before or during belt minder warning activation.
4. Turn the parklamps/headlamps on then off.
5. Buckle then unbuckle the safety belt three times ending with the safety belt unbuckled. After this step the safety belt warning lamp will be illuminated for three seconds.
6. Within seven seconds of the safety belt warning lamp turning off, buckle then unbuckle the safety belt. This will enable the belt minder if disabled or disable the belt minder if enabled.
7. The following sequence of events confirm the belt minder is enabled: zflashing of the safety belt warning belt lamp four times per second for three seconds
z three seconds with the safety belt lamp off
z flashing the safety belt lamp four times per second for three seconds again
8. The safety belt lamp flashing four times per second for three seconds provides confirmation that the belt minder is disabled. 9. After confirmation, the deactivation/activation procedure is complete. SECTION 413-
09: Warning Devices 2003 Mustang Workshop Manual Klj . 1 ba
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8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a
time and note the current drop. Do not reinstall the fuses until you are finished testing.
9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is
still excessive.
Battery— Electronic Drains Which Shut Off When the Battery Cable is Disconnected
1. Repeat the steps of the battery drain testing.
2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry
lamps to turn off if equipped.
3. Connect the ammeter and read the amperage draw.
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds
50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most
likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the
battery/central junction box one at a time to locate the problem circuit.
Generator On- Vehicle Tests
CAUTION: To prevent damage to the generator, do not make jumper wire connections
except as directed.
CAUTION: Do not allow any metal object to come in contact with the housing and the
internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Battery posts and cable clamps must be clean and tight for accurate meter indications.
NOTE: Refer to the Battery Tester Procedure Manual for complete directions for testing the charging
system.
1. Turn off all lamps and electrical components.
2. Place the vehicle in transmission range NEUTRAL and apply the parking brake.
3. Carry out the Load Test and No- Load Test according to the following component tests:
Generator On- Vehicle Tests— Load Test
1. Switch the battery tester to the ammeter function.
2. Connect the positive and negative leads of the battery tester to the corresponding battery terminals.
3. Connect the current probe to the generator B+ output terminal, circuit 38 (BK/OG). Klj . 12 ba
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