2003 FORD MUSTANG wiring

DIAGNOSIS AND TESTING
Starting System
Refer to Wiring Diagrams Cell
20 , Starting System for schematic and connector information.
Inspection and Verification WARNING: When servicing starter motor or carrying out other underhood work in the
vicinity of the starter motor, be aware that the heavy gauge battery input lead at the starter
solenoid is "electrically hot" at all times. A protective cap or boot is provided over this terminal
that must be installed after servicing. Be sure to disconnect the battery negative cable before
servicing the starter. Failure to follow these instructions may result in personal injury.
WARNING: When working in area of the starter motor, be careful to avoid touching hot
exhaust components. Failure to follow these instructions may result in personal injury.
WARNING: When using a remote starter switch or jumper wire, be sure the ignition switch
is in the OFF position and the transmission is in PARK (A/T) or Neutral (M/T) with the parking
brake control fully applied.
1. Verify the customers concern by operating the starting system to duplicate the conditions.
2. Inspect to determine if any of the following mechanical or electrical concerns apply.
3. If the inspection reveals an obvious concern that can be readily identified, repair as necessary.
4. If the concern remains after the inspection, determine the symptom. GO to Symptom Chart .
SECTION 303-
06: Starting System 2003 Mustang Workshop Manual Special Tool(s)
Digital Multimeter
105-
R0051 or equivalent Visual Inspection Chart
Mechanical Electrical
z
Starter motor
z Brackets z
Battery
z Battery junction box (BJB) fuse ignition switch (40A)
z Central junction box (CJB) Fuse 6 (20A)
z Fuse 24 (10A)
z Damaged wiring harness
z Starter Relay
z Loose or corroded connections Klj . 1 ba
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z
Measure the voltage between the central junction box fuse 6,
circuit 33 (WH/PK) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? system for normal
operation.
No
GO to
B8 .
B8 CHECK CIRCUIT 1050 (LG/VT) FOR VOLTAGE
z
Key in OFF position.
z Disconnect: Ignition Switch C209.
z Key in ON position.
z Measure the voltage between the ignition switch connector
C209 pin B4, circuit 1050 (LG/VT) and ground.
z Is the voltage greater than 10 volts? Yes
GO to
B9 .
No
REPAIR circuit 1050
(LG/VT). TEST the
system for normal
operation. B9 CHECK THE IGNITION SWITCH
z
Carry out the ignition switch component test. Refer to
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
.
z Does the ignition switch test good? Yes
REPAIR circuit 33
(WH/PK). TEST the
system for normal
operation.
No
INSTALL a new ignition
switch. TEST the
system for normal
operation.
B10 CHECK CIRCUIT 1205 (BK) FOR OPEN
z
Key in OFF position. Yes
INSTALL a new starter
motor relay. TEST the
system for normal
operation.
No
REPAIR circuit 1205
(BK). TEST the system
for normal operation. Klj . 6 ba
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Component Tests
Starter Motor —Voltage Drop Test
WARNING: When servicing starter motor or carrying out other underhood work in the
vicinity of the starter motor, be aware that the heavy gauge battery input lead at the starter
solenoid is "electrically hot" at all times. A protective cap or boot is provided over this terminal
that must be installed after servicing. Be sure to disconnect the battery negative cable before
servicing the starter. Failure to follow these instructions may result in personal injury.
WARNING: When using a remote starter switch or jumper wire, be sure the ignition switch
is in the OFF position and the transmission is in PARK (A/T) or Neutral (M/T) with the parking
brake control fully applied.
Always make the Digital Multimeter connections at the component terminal rather than at the wiring
end connector. Making a connection at the wiring end connector could result in false readings because
the meter will not pick up a high resistance between the wiring connector and the component.
Starter Motor— Motor Feed Circuit
1. Make sure the battery is fully charged. Perform a battery load test. For additional information, refer to Section 414 - 00 .
2. Disconnect the inertia fuel shut off (IFS) switch.
3. Connect a remote starter switch between the starter solenoid S- terminal and the battery positive
(+) terminal.
4. Connect the Digital Multimeter positive lead to the battery positive (+) post. Connect negative lead to the starter solenoid M- terminal. brackets for cracks.
z Check the starter motor mounting
bolts for looseness.
z Is the starter motor mounted
correctly? GO to
D2 .
No
REINSTALL the starter motor correctly. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this
section. D2 INSPECT THE STARTER MOTOR
z
Remove the starter motor; refer to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
z Inspect the starter motor for
damage.
z Is the starter motor damaged? Yes
INSTALL a new starter motor. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
TEST the system for normal operation.
No
CHECK the starter drive. REFER to Component
Tests, Starter Drive Test in this section. INSTALL a
new starter motor. TEST the system for normal
operation. Klj . 8 ba
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24. Disconnect the positive crankcase ventilation (PCV) hose.
25. Separate the fuel charging wiring harness from the fuel injection supply manifold in four places
and position the harness aside.
26. Remove the ten bolts, the intake manifold, supercharger and fuel supply manifold as an assembly.
27. Disconnect and remove the PCV hoses. Klj . 6 ba
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144 7G326 Nested spring
— 1-2 (inner spring) (vehicle
dependent) 145 7F247 Cover and seal assembly — 1-
2 accumulator 146 7384 Ring — 2-
1/16 retaining type HU internal (retains
7H300 to 7005) 147 N807178-
S1000 Bolt —
M6-1.0 x 18 hex head (12- attaches
reinforcing plate to valve body) 148 7F282 Plate —
valve body reinforcing (part of 7A100) 149 7C155 Gasket —
valve body separator upper 150 7A008 Plate —
control valve body separator (part of
7A100) 151 7D100 Gasket —
valve body separator lower 152 7D174 Valve —
converter drainback 153 7A091 Body assembly —
main control 154 7H173 Gasket —
valve body cover plate 155 7C034 Plate —
valve body cover (part of 7A100) 156 N807178-
S1000 Bolt —
M6-1.0 x 18 hex head (11- attaches 7C034
to 7A100 (part of 7A100) 157 7A100 Control assembly —
main (model dependent) 158 7A098 Filter and seal assembly —
fluid 159 7A191 Gasket —
transmission pan 160 7A194 Pan — transmission
161 N605785-
S1036 Bolt —
M8-1.25 x 18 hex flange head (14-
attaches 7A194 to 7005) 162 7L027 Magnet —
ceramic case (part of 7A194) 163 N808947-
S1300 Bolt —
M8-1.25 x 46 hex shoulder pilot (2-
attaches 7C034 to 7A100) 164 N807179-
S1000 Bolt —
M6-1.0 x 52 hex flange head (12- attaches
7A100 to 7005) 165 7H111 Retainer — solenoid
166 7E195 Ball —
1/4 diameter coast booster valve shuttle (8
req'd) 167 7H187 Screen —
solenoid pressure supply 168 N800670-
S1000 Bolt —
M6-1.0 x 40 hex flange head (13- attaches
7A100 to 7005) 169 7E332 Spring assembly —
manual valve detent 170 7Z276 Seal —
0.864 x 0.070 O- ring (2 req'd) 171 7G276 Bulkhead assembly — wiring connector
172 7G276 Bulkhead assembly —
connector (molded lead
frame) 173 7Z484 Seal —
6.07 x 1.70 O- ring (2 req'd) 174 7G484 Solenoid valve —
transmission shift 175 7G136 Solenoid valve —
transmission torque converter
clutch 176 N807178-
S1000 Bolt —
M6-1.0 x 16 hex head (retains 7D136 and
7G484 to 7A100) Klj . 7 ba
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DIAGNOSIS AND TESTING
Diagnostic Strategy
Troubleshooting an electronically controlled automatic transmission is simplified by using the proven
method of diagnosis. One of the most important things to remember is that there is a definite
procedure to follow.
NOTE:
Do not take any short cuts or assume that critical checks or adjustments have already been
made.
Follow the procedures as written to avoid missing critical components or steps.
To properly diagnose a concern have the following publications available:
zTransmission Reference Manual.
z Powertrain Control/Emissions Diagnosis (PC/ED) manual.
z TSBs and OASIS Messages.
z Wiring Diagram.
These publications provide the information required when diagnosing transmission concerns.
Use the Diagnostic Flow Chart as a guide and follow the steps as indicated.
Preliminary Inspection
zKnow and understand the customer's concern.
z Verify the concern by operating the vehicle.
z Check the fluid levels and condition.
z Check for non-factory add- on items.
z Check shift linkages for proper adjustment.
z Check TSBs and OASIS messages regarding the concern.
Diagnostics
zCarry out on- board diagnostic procedures key on engine off (KOEO) and key on engine running
(KOER).
z Record all diagnostic trouble codes (DTCs).
z Repair all non- transmission codes first.
z Repair all transmission codes second.
z Erase all continuous codes and attempt to repeat them.
z Repair all continuous codes.
z If only pass codes are obtained, refer to Diagnosis By Symptom for further information and
diagnosis.
Follow the diagnostic sequence to diagnose and repair the concern the first time. SECTION 307-
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DIAGNOSIS AND TESTING
Visual Inspection
This inspection will identify modifications or additions to the vehicle operating system that may affect
diagnosis. Inspect the vehicle for non-
Ford factory add-on devices such as:
z electronic add- on items:
„ air conditioning
„ generator (alternator)
„ engine turbo
„ cellular telephone
„ cruise control
„ CB radio
„ linear booster
„ backup alarm signal
„ computer
z Vehicle modification:
These items, if not installed correctly, will affect the powertrain control module (PCM), or transmission
function. Pay particular attention to add- on wiring splices in the PCM harness or transmission wiring
harness, abnormal tire size, or axle ratio changes.
zLeaks; refer to Leak Inspection.
z Correct linkage adjustments; refer to Section 307 - 05 .
Shift Linkage Check
Check for a misadjustment in shift linkage by matching the detents in the transmission range selector
lever with those of the manual lever in the transmission. If they match, the misadjustment is in the
indicator. Do not adjust the shift linkage.
Hydraulic leakage at the manual control valve can cause delay in engagements and/or slipping while
operating if the linkage is not correctly adjusted. Refer to Section 307 - 05 for shift linkage adjustment.
Check TSBs and OASIS
Refer to all technical service bulletins (TSB) and OASIS messages which pertain to the transmission
concern and follow the procedure as described.
Carry Out On- Board Diagnostics (KOEO, KOER)
After a road test, with the vehicle warm and before disconnecting any connectors, carry out the Quick
Test using the scan tool. Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual. SECTION 307-
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DIAGNOSIS AND TESTING
Transmission Drive Cycle Test
NOTE:
Always drive the vehicle in a safe manner according to driving conditions and obey all traffic
laws.
NOTE: The Transmission Drive Cycle Test must be followed exactly. Malfunctions must occur four
times consecutively for shift error DTC code to be set, and five times consecutively for continuous TCC
code to set.
NOTE: When carrying out the Transmission Drive Cycle Test, refer to the Solenoid Application Chart
for correct solenoid operation.
After carrying out the Quick Test, use the Transmission Drive Cycle Test for checking continuous
codes.
1. Record and then erase Quick Test codes.
2. Warm engine to normal operating temperature.
3. Make sure transmission fluid level is correct.
4. With transmission in OVERDRIVE, moderately accelerate from stop to 80 km/h (50 mph). This allows the transmission to shift into fourth gear. Hold speed and throttle open steady for a
minimum of 15 seconds.
5. With transmission in fourth gear and maintaining steady speed and throttle opening, lightly apply and release brake to operate stoplamps. Then hold speed and throttle steady for a
minimum of five seconds.
6. Brake to a stop and remain stopped for a minimum of 20 seconds.
7. Repeat steps 4 through 6 at least five times.
8. Carry out Quick Test and record continuous DTCs. zIf the DTCs are still present, refer to the Diagnostic Trouble Code Chart. Repair all non
transmission DTCs first as they can directly affect the operation of the transmission.
Repeat the Quick Test and the Road Test to verify the correction. Erase the DTCs, carry
out the Drive Cycle Test and repeat the Quick Test after completing repair on the DTC.
z If the continuous test passes and a concern is still present, refer to Diagnosis By Symptom in this section, OASIS messages, and TSBs for concerns.
After On- Board Diagnostic
NOTE: The vehicle wiring harness, PCM and non- transmission sensors may affect transmission
operations. Repair these concerns first.
After the on- board diagnostic procedures are completed, repair all DTCs.
Begin with non- transmission related DTCs, then repair any transmission related DTCs. Use the
diagnostic trouble code chart for information on condition and symptoms. This chart will be helpful in
referring to the correct manual(s) and aids in diagnosing internal transmission concerns and external
non- transmission inputs. The pinpoint tests are used in diagnosing transmission electrical concerns.
Make sure that the vehicle wiring harness and the PCM are diagnosed as well. The Powertrain SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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