key FORD MUSTANG 2003 Workshop Manual

z
Is the resistance more than 10,000 ohms? G8 CHECK CIRCUIT 249 (DB/LG) FOR AN OPEN CIRCUIT
z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Measure the resistance between C238- 3, circuit 249
(DB/LG), harness side and C294c- 4 harness side.
z Is the resistance more than 10,000 ohms? Yes
REPAIR circuit 249
(DB/LG) for an open. TEST
the system for normal
operation.
No
GO to
G9 .
G9 CHECK CIRCUIT 181 (BN/OG), FOR VOLTAGE
z
Measure the voltage between C294c- 2, circuit 181 (BN/OG),
harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new function
selector switch. REFER to
Section 412
- 04 . TEST the
system for normal
operation.
No
REPAIR circuit 181
(BN/OG) for an open. TEST
the system for normal
operation. G10 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
Yes
INSTALL a new blower
motor switch. REFER to
Section 412
- 04 . TEST the
system for normal
operation.
No
REPAIR circuit 1205 (BK).
TEST the system for
normal operation. Klj . 33 ba
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PINPOINT TEST H: THE BLOWER MOTOR OPERATES
CONTINUOUSLY IN HIGH SPEED z
Check the resistance between C294a- 3, circuit 1205 (B/K)
harness side and ground.
z Is the resistance less than 5 ohms? Test Step Result / Action to Take
H1 CHECK THE FUNCTION SELECTOR SWITCH
z
Key in ON position.
z Set the blower motor speed to low.
z Check for blower motor operation in each function
selector switch position.
z Does the blower motor operate on high in all of
the function selector positions? Yes
GO to
H2 .
No
If the blower motor operates in the
OFF position, GO to H4 .
H2 CHECK CIRCUIT 261 (OG/BK) FOR A SHORT TO
GROUND z
Key in OFF position.
z Disconnect: A/C Blower Motor C2066.
z Disconnect: Blower Motor Resistor C2185.
z Disconnect: Blower Motor Switch C294a.
z Measure the resistance between C2066 circuit 261
(OG/BK), and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
H3 .
No
REPAIR circuit 261 (OG/BK) for a
short to ground. TEST the system
for normal operation. H3 CHECK THE BLOWER MOTOR SWITCH
OPERATION z
Measure the resistance of the blower motor switch.
Refer to the chart shown.
Blower Motor Switch Test Switch
Position Conductivity Between
Terminals Yes
INSTALL a new heater blower
motor switch resistor. REFER to
Section 412
- 04 . TEST the
system for normal operation.
No Klj . 34 ba
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PINPOINT TEST I: NO OPERATION IN HIGH BLOWER SETTING z
Is the resistance less than 5 ohms? Low None
Medium/low 2 and 3 only
Medium/high 2, 3 and 4 only
High 1, 2 and 4 only INSTALL a new heater blower
motor switch. REFER to
Section 412 - 04 . TEST the system for
normal operation. H4 CHECK THE FUNCTION SELECT SWITCH FOR A
SHORT TO BATTERY z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Key in ON position.
z Did the blower motor stop operating? Yes
INSTALL a new function selector
switch. REFER to
Section 412 -
04 . TEST the system for normal
operation.
No
REPAIR circuit 249 (DB/LG) for a
short to battery. TEST the system
for normal operation. Test Step Result / Action to Take
I1 CHECK CIRCUIT 261 (OG/BK) FOR AN OPEN CIRCUIT
z
Key in OFF position.
z Disconnect: Blower Motor Switch C294a.
z Key in ON position.
z Turn the function selector switch to the FLOOR position.
z Measure the voltage between blower motor switch C294a,
circuit 261 (OG/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
I2 .
No
REPAIR circuit 261 (OG/BK)
for an open circuit. TEST the
system for normal operation. I2 CHECK CIRCUIT 1205 (BK) FOR AN OPEN Klj . 35 ba
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PINPOINT TEST J: NO OPERATION IN LOWER SPEEDS
Component Tests z
Measure the resistance between C294a- 3, circuit 1205
(BK), harness side and ground.
z Is the resistance less than 10,000 ohms? Yes
REPAIR circuit 1205 (BK) for
an open. TEST the system for
normal operation.
No
INSTALL a new blower motor
switch. REFER to
Section 412 - 04 . TEST the system for
normal operation. Test Step Result / Action to Take
J1 CHECK CIRCUIT 261 (OG/BK) FOR AN OPEN
z
Disconnect: Blower Motor Resistor C294a.
z Key in ON position.
z Turn the function selector switch to the FLOOR position.
z Set the blower motor switch to low.
z Measure the voltage between the blower motor resistor
C2185- 4, circuit 261 (OG/BK), jumper side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
J2 .
No
REPAIR circuit 261 (OG/BK) for
an open circuit between the
blower motor and the blower
motor resistor. TEST the
system for normal operation. J2 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between the blower motor
resistor C2185- 1, circuit 1205 (BK), jumper side and
ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new blower motor
resistor. REFER to
Section 412 -
03 . TEST the system for
normal operation.
No
REPAIR circuit 1205 (BK) for an
open between the blower motor
resistor and ground. TEST the
system for normal operation. Klj . 36 ba
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Pinpoint Tests
PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE
PINPOINT TEST B: THE INSTRUMENT CLUSTER ILLUMINATION IS
INOPERATIVE z
Bulb(s).
z The climate control
illumination is inoperative z
Circuitry.
z Bulb(s). z
Go To Pinpoint Test C .
z The audio system
illumination is inoperative z
Circuitry.
z Audio unit. z
Go To Pinpoint Test D .
z A single illumination source
is inoperative z
Circuitry.
z Switch. z
Go To Pinpoint Test E .
Test Step Result / Action to Take
A1 CHECK PARKING LAMPS
z
Place the headlamp switch in the ON
position.
z Are the exterior lamps on? Yes
Place the headlamp switch in the OFF position.
GO to
A2 .
No
REFER to Section 417 - 01 .
A2 CHECK HEADLAMP SWITCH
z
Key in OFF position.
z Carry out the headlamp switch
components test;
Refer to Wiring Diagrams Cell 149 for
schematic and connector information.
.
z Is the headlamp switch OK? Yes
RECONNECT the headlamp switch. GO to
A3 .
No
INSTALL a new headlamp switch. REFER to
Section 417 - 01 . TEST the system for normal
operation. A3 CHECK CIRCUIT 1045 (DB/WH)
z
Place the headlamp switch in the ON
position.
z Rotate the instrument panel dimmer
switch to the full illumination position.
z Measure voltage between central
junction box (CJB) fuse 37 (5A) and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR circuit 19 (LB/RD). TEST the system for
normal operation.
No
REPAIR circuit 1045 (DB/WH). TEST the system
for normal operation.
Test Step Result / Action to Take
B1 CHECK VOLTAGE TO INSTRUMENT CLUSTER
ILLUMINATION z
Disconnect: Instrument Cluster .
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full Yes
GO to
B2 . Klj . 2 ba
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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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GEM Diagnostic Trouble Code (DTC) Index
DTC Description Source Action
B1218 Horn Relay Coil Circuit Short to
VBatt GEM REFER to
Section 501 - 14B .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU is Defective GEM Clear the DTCs. Retrieve the DTCs. If DTC B1342
is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1408 Driver Power Window Up
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM Go To Pinpoint Test K .
B1428 Lamp Safety Belt Circuit Failure GEM Go To Pinpoint Test K .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay Coil
Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay Coil
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 . Klj . 8 ba
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A1 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
A2 .
No
REPAIR the circuit.
TEST the system
for normal
operation. A2 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.
z Is the voltage greater than 10 volts? Yes
GO to
A3 .
No
REPAIR the circuit.
TEST the system
for normal
operation. A3 CHECK THE RUN/START POWER SUPPLY TO THE INSTRUMENT
CLUSTER 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 12,
circuit 20 (WH/LB), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A4 .
No
REPAIR the circuit.
TEST the system
for normal
operation. Klj . 14 ba
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PINPOINT TEST B: INCORRECT FUEL GAUGE INDICATION A4 CHECK GROUND CIRCUIT 397 (BK/WH) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between the instrument cluster C220b pin
20, circuit 397 (BK/WH), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
A5 .
No
REPAIR the circuit.
TEST the system
for normal
operation. A5 CHECK GROUND CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between the instrument cluster C220b pin 1,
circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
REFER to
Section 418 - 00 .
No
REPAIR the circuit.
TEST the system
for normal
operation. Test Step Result / Action to
Take B1 CARRY OUT THE INSTRUMENT CLUSTER FUEL GAUGE
ACTIVE COMMAND CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector. NOTE: Fuel fills of less
than 9.5 liters (2.5 gallons) require at least 10 minutes to update
the fuel gauge indication.
z Key in ON position.
z Select the instrument cluster FUELLEVEL active command.
Trigger, monitor, and scroll FUELLEVEL at: 0% , 50%, and
100%.
z Does the fuel gauge display: below E at 0%, half at 50%, and
F at 100%? Yes
GO to
B2 .
No
GO to B8 .
B2 CHECK THE FUEL GAUGE OPERATION
z
Key in OFF position.
z Disconnect: Fuel Pump Assembly C463.
z Connect one lead of the Instrument Gauge System Tester to the
fuel pump module C463 pin 5, circuit 29 (YE/WH), harness side
and the other lead of the Instrument Gauge System Tester to the Yes
GO to
B3 .
No
GO to B5 . Klj . 15 ba
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fuel pump module C463 pin 8, circuit 327 (BK/OG), harness side.
z Set the Instrument Gauge System Tester to 160 ohms.
z Key in ON position.
z Turn the ignition switch to RUN for one second.
z Key in OFF position.
z Set Instrument Gauge System Tester to 15 ohms.
z Key in ON position.
z NOTE: The fuel gauge should read E or below when carrying out
this test step.
z Wait one minute and read the fuel gauge.
z Key in OFF position.
z Set Instrument Gauge System Tester to 160 ohms.
z Key in ON position.
z NOTE: The fuel gauge should read F (full) or above when
carrying out this test step.
z Wait one minute and read the fuel gauge.
z Key in OFF position.
z Does the fuel gauge operate correctly? B3 CHECK THE FUEL TANK
z
Check the fuel tank for any damage or deformation.
z Is the fuel tank OK? Yes
GO to
B4 .
No
INSTALL a new fuel
tank; REFER to
Section 310 - 01 . TEST
the system for normal
operation. B4 CHECK THE FUEL PUMP ASSEMBLY
z
Check the fuel pump assembly in- tank mounting, float, float rod,
wiring and connections for damage or obstruction.
z Is the fuel pump assembly and wiring OK? Yes
INSTALL a new fuel
sender. TEST the
system for normal
operation.
No
REPAIR as necessary.
TEST the system for
normal operation.
B5 CHECK CIRCUIT 29 (YE/WH) FOR SHORT TO POWER
z
Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the instrument cluster C220b pin
19, circuit 29 (YE/WH), harness side and ground. Yes
REPAIR the circuit.
TEST the system for
normal operation.
No
GO to
B6 . Klj . 16 ba
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