2003 FORD MUSTANG ECO mode

PINPOINT TEST N: THE CHECK FUEL CAP INDICATOR IS NEVER
ON Test Step Result / Action to Take
M1 CHECK THE O/D OFF
INDICATOR OPERATION z
Key in ON position.
z Observe the O/D OFF indicator.
z Is the O/D OFF indicator
always on? Yes
GO to
M2 .
No
GO to M3 .
M2 CHECK THE INSTRUMENT
CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster
C220a.
z Key in ON position.
z Observe the O/D OFF indicator.
z Did the indicator turn off? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M3 CHECK THE INSTRUMENT
CLUSTER OPERATION z
Carry out the instrument cluster
self- diagnostic mode.
z Did the O/D OFF indicator
illuminate? Yes
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
M4 .
M4 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
N1 RETREIVE AND RECORD DTCS FROM
CONTINUOUS AND ON- DEMAND SELF-TESTS—
PCM NOTE:
Once the check fuel cap indicator
does turn on, it does not turn off unless the
fuel cap has been correctly secured and the
vehicle has been driven for several minutes.
z Use recorded PCM DTCs from the
continuous and on- demand self-test.
z Are any DTCs recorded? Yes
If PCM DTC P0457, REFER to the
Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
N2 .
N2 CARRY OUT THE INSTRUMENT CLUSTER Klj . 27 ba
412003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

z
Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch
states? F2 DETERMINE IF THE GEM IS RECEIVING CORRECT
SAFETY BELT SWITCH STATUS z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT read OUT and IN
correctly? Yes
GO to
F3 .
No
GO to F5 .
F3 CHECK THE GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
F4 .
No
GO to F11 .
F4 CHECK THE SAFETY BELT WARNING LAMP OPERATION
z
Cycle the ignition switch from OFF to RUN while monitoring
the instrument cluster safety belt indicator lamp.
z Does instrument cluster safety belt indicator lamp
illuminate for approximately three seconds? Yes
GO to
F11 .
No
REFER to Section 413 - 01 .
F5 DETERMINE IF CIRCUIT 85 (BN/LB) IS OPEN OR
SHORTED TO GROUND z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT, while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT value indicate OUT with
the driver safety belt buckled? Yes
GO to
F6 .
No
GO to F8 .
F6 ISOLATE THE SHORT TO GROUND ON CIRCUIT 85
(BN/LB) z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT.
z Does the GEM PID D_SBELT value indicate IN? Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
F7 .
F7 CHECK CIRCUIT 85 (BN/LB) FOR A SHORT TO GROUND
BETWEEN GEM AND SAFETY BELT SWITCH z
Disconnect: GEM C201d.
z Measure the resistance between GEM C201d pin 8, circuit
85 (BN/LB), harness side and ground. Yes
GO to
F11 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 18 ba
202003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests speakers
zSubwoofer
amplifier.
z Circuitry. E .
z Poor quality sound from one or
more speakers (not all
speakers) z
Speaker(s).
z Circuitry.
z Audio unit.
z Subwoofer
amplifier. z
Go To Pinpoint Test F .
z Poor quality sound from all
speakers z
Audio unit.
z Speaker(s).
z Circuitry. z
Go To Pinpoint Test G .
z The subwoofer is inoperative zSubwoofer.
z Subwoofer
amplifier.
z Circuitry. z
Go To Pinpoint Test H .
z Loud popping when cycling the
ignition switch z
Audio unit.
z Circuitry. z
Go To Pinpoint Test I .
z One or more audio control
buttons (such as volume, seek,
tune and scan) are not
functional in either radio, tape,
or CD mode or all modes z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z When the headlamp switch is in
park or headlamp position and
the ignition switch is in the RUN
or ACC position, the audio unit
back lighting is inoperative — all
other I/P lighting functions are
normal z
Circuitry.
z Audio unit. z
REFER to Section 413 - 00 .
z The audio unit has two items
that can be dimmed— the audio
unit display and the control
buttons; one dims and the other
does not z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Irregular operation of display
and indicator LEDs z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Response time between
pressing any of the audio
control buttons and system
response is more than two
seconds z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation. Klj . 3 ba
242003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Communications Network
Refer to Wiring Diagrams Cell
14 , Multiplex Communication Network for schematic and connector
information.
Principles of Operation
The vehicle has two module communications networks. The standard corporate protocol (SCP) which
is an unshielded twisted pair cable (data bus plus, Circuit 914 [TN/OG] and data bus minus, Circuit 915
[PK/LB]), and the international standards organization (ISO) 9141 network which is a single wire
(Circuit 70 [LB/WH]). The diagnostic tool can connect to both networks through the data link connector
(DLC). This makes diagnosis and testing of these systems easier by allowing one smart tester to be
able to diagnose and control any module on the two networks from one connector. The DLC can be
found under the instrument panel between the steering column and the radio.
The ISO 9141 communication network does not permit inter- module communication. When the
diagnostic tool communicates to modules on the ISO 9141 communication network, the diagnostic tool
must ask for all information; the modules cannot initiate communications.
The SCP network will remain operational even with the severing of one of the bus wires.
Communications will also continue if one of the bus wires is shorted to ground or battery positive
voltage (B+) or if some, but not all, termination resistors are lost.
Unlike the SCP communication network, the ISO 9141 communication network will not function if the
wire is shorted to chassis ground or battery positive voltage (B+). Also, if one of the modules on the
ISO 9141 network loses power or shorts internally, communications to that module will fail.
The powertrain control module (PCM) is on the SCP communication network. The PCM controls the
engine for better fuel economy, emissions control, and failure mode detection and storage. Refer to
Powertrain Control/Emissions Diagnosis (PC/ED) manual Section 3 for diagnosis and testing of the
PCM.
The restraint control module (RCM) is on the ISO 9141 network. The RCM controls the deployment of
the air bags based on sensor input. For additional information, refer to Section 501 - 20B .
SECTION 418-
00: Module Communications Network 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051 Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Klj . 1 ba
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
CAUTION: Be careful when probing the CJB, battery junction box (BJB) or any
connectors. Damage will result to the connector receptacle if the probe or terminal being used
is too large.
CAUTION: Electronic modules are sensitive to static electrical charges. If exposed to
these charges, damage may result.
NOTE: If DTCs are recorded and the symptom is not present when carrying out the pinpoint tests, an
intermittent concern may be the cause. Always check for loose connections and corroded pins.
PINPOINT TEST A: THE MODULE DOES NOT RESPOND TO THE
DIAGNOSTIC TOOL — ANTI-LOCK BRAKE CONTROL MODULE tool —
instrument cluster zInstrument cluster. Test D .
z The module does not
respond to the diagnostic
tool — powertrain control
module (PCM) z
Wire or connection in SCP
communication network.
z PCM. z
GO to
Pinpoint Test E .
z No module/network
communication — ISO 9141
network z
Wire or connection in ISO
9141 communication
network.
z ISO 9141 networked
modules. z
GO to
Pinpoint Test F .
z No module/network
communication — SCP
network z
Wire or connection in SCP
communication network.
z SCP networked modules. z
GO to
Pinpoint Test G .
z No module/network
communication — no power
to the diagnostic tool z
CJB Fuse 31 (5A).
z DLC pins.
z Scan tool.
z Circuitry. z
GO to
Pinpoint Test H .
Test Step Result / Action to Take
A1 CHECK THE VEHICLE FOR TRACTION CONTROL
z
Check the vehicle for a traction control disable switch.
z Is a traction control disable switch present? Yes
GO to
A2 .
No
GO to A9 .
A2 CHECK ANTI-
LOCK BRAKE CONTROL MODULE C141
FOR DAMAGE z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Inspect the anti- lock brake control module C135 for
damage; repair as necessary.
z Connect: Anti- Lock Brake Control Module C135.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link. Yes
GO to
A3 .
No
GO to A6 . Klj . 4 ba
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST B: THE ANTI-
THEFT INDICATOR IS
ALWAYS/NEVER ON — NO THREE SECOND THEFT INDICATOR
PROVE OUT CLUSTER
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 Circuit 20
(WH/LB). REPEAT the
self- test. CLEAR the
DTCs. A4 CHECK GROUND CIRCUIT 397 (BK/WH) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between 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.
REPEAT the self- test.
CLEAR the DTCs. A5 CHECK GROUND CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between 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.
REPEAT the self- test.
CLEAR the DTCs. Test Step Result / Action to Take
B1 ENTER THE INSTRUMENT CLUSTER ACTIVE
COMMAND MODE Klj . 5 ba
182003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST D: THE ANTI-
THEFT SYSTEM DOES NOT OPERATE
CORRECTLY — ANTI-THEFT NUMBER OF PROGRAMMED KEYS IS
BELOW MINIMUM diagnostic mode on the
diagnostic tool: Clear
Continuous DTCs.
z Enter the following
diagnostic mode on the
diagnostic tool: PCM
Self- Test.
z Does diagnostic tool
communicate with the
PCM? C3 RETRIEVE THE PCM
DTCS z
Retrieve and document
continuous DTCs.
z Is DTC P1260
recorded? Yes
GO to
C4 .
No
VERIFY PCM power and ground. REFER to Powertrain
Control/Emissions Diagnosis (PC/ED) manual Section 3. C4 CHECK THE
COMMUNICATION
NETWORK z
Repeat Inspection and
Verification steps 3
through 7; refer to
Inspection and
Verification.
z Key in OFF position.
z Retrieve and document
continuous DTCs.
z Enter the following
diagnostic mode on the
diagnostic tool: Clear
Continuous DTCs.
z Enter the following
diagnostic mode on the
diagnostic tool:
Instrument Cluster On-
Demand Self- Test.
z Is DTC U1147
retrieved? Yes
INSTALL a new instrument cluster; for additional information,
REFER to
Section 413 - 01 . CYCLE the ignition to RUN using
two encoded ignition keys. Go To Pinpoint Test J to initialize the
module. REPEAT the self- test. CLEAR the DTCs. If DTC U1147
is still present, INSTALL a new PCM; for additional information,
REFER to Section 303 - 14 . TEST the system for normal
operation. (You must follow Pinpoint Test J to initialize module.)
No
System is OK. Test Step Result / Action to Take
D1 USE THE DTCS FROM THE
INSTRUMENT CLUSTER SELF- TESTS z
Use the recorded results from the
Instrument Cluster Continuous and
On- Demand Self- Tests.
z Is DTC B1213 the only DTC
retrieved? Yes
GO to
D2 .
No
REPAIR the other DTCs retrieved. REPEAT the
Instrument Cluster On- Demand Self-Test. CLEAR
the DTCs. D2 CHECK FOR PROGRAMMED Klj . 7 ba
182003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST E: THE ANTI-
THEFT SYSTEM DOES NOT OPERATE
CORRECTLY — ANTENNA NOT CONNECTED OR DEFECTIVE
TRANSCEIVER
PINPOINT TEST F: THE ANTI- THEFT SYSTEM DOES NOT OPERATE
CORRECTLY — PATS IGNITION KEY TRANSPONDER SIGNAL IS
NOT RECEIVED (DAMAGED KEY OR NON- PATS KEY) ENCODED IGNITION KEYS —
MONITOR THE INSTRUMENT
CLUSTER PID NUMKEYS
z
Monitor the instrument cluster PID
NUMKEYS.
z Does the instrument cluster PID
NUMKEYS display less than two
encoded ignition keys
programmed? Yes
GO to
D3 .
No
System is OK. D3 PROGRAM ENCODED IGNITION
KEYS z
NOTE: Two programmed encoded
ignition keys must be available to
start the vehicle.
z Cut a new encoded ignition key.
z Key in ON position.
z Program the new encoded ignition
key.
z Does the theft indicator
illuminate for three seconds, and
then go out? Yes
CLEAR the DTCs. CARRY OUT the Instrument
Cluster On-
Demand Self- Test to verify all codes
have been cleared. REPEAT the self- test. CLEAR
the DTCs.
No
If the theft indicator is on continuously, REPEAT
TEST STEP D3 with a second new encoded ignition
key. If the theft indicator is flashing, RETRIEVE
DTCs stored for the new fault and REPAIR the other
DTC(s) retrieved. Test Step Result / Action to Take
E1 INSPECT THE PATS
TRANSCEIVER FOR CORRECT
INSTALLATION z
Key in OFF position.
z Verify the PATS transceiver is
correctly installed; refer to
Module — Passive Anti - Theft
Transceiver .
z Connect the diagnostic tool.
z Enter the following diagnostic
mode on the diagnostic tool:
Instrument Cluster On- Demand
Self- Test.
z Retrieve and document
continuous DTCs.
z Enter the following diagnostic
mode on the diagnostic tool:
Clear Continuous DTCs.
z Is DTC B1232 or B2103
retrieved? Yes
INSTALL a new PATS transceiver module; for
additional information, REFER to
Module — Passive
Anti - Theft Transceiver . REPEAT the Instrument
Cluster On- Demand Self- Test. CLEAR the DTCs.
No
System is OK. Klj . 8 ba
182003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...