2003 FORD MUSTANG instrument cluster

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
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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 ba
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Pinpoint Tests
CAUTION: Do not make jumper connections except as directed. Incorrect connections
may damage the voltage regulator test terminals, fuses, or fuse links.
CAUTION: Do not allow any metal object to come in contact with the generator housing
and internal diode cooling fins.
NOTE: All voltage measurements are referenced to the negative (- ) battery post unless otherwise
specified. PINPOINT TEST A: BATTERY IS DISCHARGED OR VOLTAGE IS Symptom Chart
Condition
Possible Sources Action
z Battery is discharged or voltage is
low z
Circuitry.
z High key- off current
drain(s).
z Battery.
z Generator. z
Go To Pinpoint
Test A .
z The charging system warning
indicator is on with the engine
running (the system voltage does
not increase) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test B .
z The system overcharges (the
battery voltage is greater than 15.5
volts) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test C .
z The charging system warning
indicator is on with the engine
running and the battery increases
voltage z
Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test D .
z The charging system warning
indicator is off with the ignition
switch in the RUN position and the
engine off z
Bulb.
z Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test E .
z The charging system warning
indicator flickers or is intermittent z
Central junction box
(CJB) fuse 5 (15A).
z Generator
connector
unplugged (C102a).
z Circuitry.
z Generator. z
Go To Pinpoint
Test F .
z The generator is noisy zBolts or brackets.
z Drive belt.
z Generator or pulley. z
Go To Pinpoint
Test G .
z Radio interference zGenerator.
z Circuitry.
z In-vehicle
entertainment
system. z
Go To Pinpoint
Test F . Klj . 4 ba
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INCREASES VOLTAGE
PINPOINT TEST E: THE CHARGING SYSTEM WARNING INDICATOR
IS OFF WITH THE IGNITION SWITCH IN THE RUN POSITION AND
THE ENGINE OFF
PINPOINT TEST F: THE CHARGING SYSTEM WARNING INDICATOR
LAMP FLICKERS OR IS INTERMITTENT
Test Step Result / Action to Take
D1 CHECK I CIRCUIT 904 (LG/RD) FOR A
SHORT TO GROUND z
Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in ON position.
z With the ignition switch in the RUN position,
check the charging system warning
indicator.
z Is the charging system warning indicator
illuminated? Yes
REPAIR circuit 904 (LG/RD) for a short to
ground. TEST the system for normal
operation.
No
INSTALL a new generator. REFER to
Section 414
- 02 . TEST the system for
normal operation. Test Step Result / Action to
Take E1 CHECK THE CHARGING SYSTEM WARNING INDICATOR
LAMP z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z With the engine off, connect a fused (15A) jumper wire between
the generator C102c (4.6L 4V) or C102a (3.8L or 4.6L 2V) pin 1,
circuit 904 (LG/RD), harness side and ground.
z Key in ON position.
z Is the charging system warning indicator lamp illuminated? Yes
INSTALL a new
generator. REFER to
Section 414
- 02 . TEST
the system for normal
operation.
No
REFER to Section 413 - 01 for diagnosis
and testing of the
instrument cluster. Test Step Result / Action to
Take F1 CHECK FOR LOOSE CONNECTIONS
z
Check all generator, battery, and power distribution connections
for looseness, corrosion, loose or bent terminals, or loose eyelets.
z Are all connections clean and tight? Yes
GO to
F2 .
No Klj . 8 ba
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REMOVAL AND INSTALLATION
Lamp Switch —
Headlamp
Removal 1. Disconnect the battery ground cable.
2. Remove the headlamp switch knob. 1. Pull the headlamp switch knob out.
2. Insert a thin tool into the slot, pull and remove the headlamp switch knob.
3. Remove the instrument panel cluster finish panel. zRemove the screws and remove the finish panel.
4. Remove the headlamp switch. 1. Remove the screws.
2. Remove the switch.
3. Disconnect the electrical connectors.
SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Klj . 1 ba
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The generic electronic module (GEM) is on the ISO 9141 network. The GEM module controls a variety
of systems including one touch down windows, wipers, perimeter anti-
theft, and warning chimes. For
additional information, refer to Section 419 - 10 .
The anti- lock brake control module communicates over the ISO 9141 communication network when
not equipped with traction control and communicates over the SCP communication network when it is
equipped with the traction control option. The anti- lock brake control module controls the brake
pressure to the four wheels to keep the vehicle under control while braking. For additional information
on anti- lock brake control module without traction control, refer to Section 206 - 09A . For additional
information on anti- lock brake control module with traction control, refer to Section 206 - 09B .
The instrument cluster is on the SCP communication network. The instrument cluster displays driver
information. The instrument cluster incorporates the PATS control module functions. For additional
information on the PATS system, refer to Section 419 - 01 . For additional information on the instrument
cluster, refer to Section 413 - 01 .
Inspection and Verification 1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage.
3. If the concern remains after the inspection, connect diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from diagnostic
tool menu. If diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check that the correct version of the program card is installed.
z check the connections to the vehicle.
z check the ignition switch position.
If the diagnostic tool still does not communicate with the vehicle, go to Pinpoint Test H. 4. Go to Pinpoint Test PC.
System Precheck Visual Inspection Chart Electrical
z
Central junction box (CJB) Fuse 31 (5A)
z Damaged wiring harness
z Loose or corroded connections
z Anti- lock brake control module without traction control (optional)
z Anti- lock brake control module with traction control (optional)
z Generic electronic module (GEM)
z Restraint control module (RCM)
z Powertrain control module (PCM)
z Instrument cluster Klj . 2 ba
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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
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PINPOINT TEST D: THE MODULE DOES NOT RESPOND TO THE
DIAGNOSTIC TOOL —
INSTRUMENT CLUSTER (LB/WH), harness side and RCM C2041 Pin 5, Circuit 70
(LB/WH), harness side.
z Is the resistance less than 5 ohms? REPAIR Circuit 70
(LB/WH) between RCM
C2041 and DLC C251 .
TEST the system for
normal operation.
Test Step Result / Action to Take
D1 CHECK INSTRUMENT CLUSTER C220a FOR DAMAGE
z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Inspect instrument cluster C220a for damage; repair as
necessary.
z Connect: Instrument Cluster C220a.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link.
z Was the result received ICM: NO RESPONSE ON
CKT914 (BUS+)? Yes
GO to
D2 .
No
GO to D3 .
D2 CHECK FOR OPEN BETWEEN DLC C251 PIN 2 AND
INSTRUMENT CLUSTER C220a PIN 1 — CIRCUIT 914
(TN/OG) z
Key in OFF position.
z Disconnect the diagnostic tool.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance between instrument cluster
C220a Pin 1, Circuit 914 (TN/OG), harness side and
DLC C251 Pin 2, Circuit 914 (TN/OG), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new instrument
cluster. For additional
information, REFER to
Section 413 - 01 . TEST the system for
normal operation.
No
REPAIR Circuit 914 (TN/OG)
between instrument cluster
C220a and DLC C251. For
additional information, REFER
to Communication Circuit Wiring Repair . TEST the system for
normal operation. D3 CHECK FOR OPEN BETWEEN DLC C251 PIN 10 AND
INSTRUMENT CLUSTER C220a PIN 2 — CIRCUIT 915
(PK/LB) z
Key in OFF position. Yes Klj . 9 ba
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