FORD MUSTANG 2003 Workshop Manual

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
Diagnostic Flow Chart
SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Diagnostic Flow Chart
z
Know and understand
the customer concerns
z Check the fluid level
and condition
z Verify the concern by
operating the vehicle
z Check for non- factory-
installed items and
verify correct installation
z Check the shift linkage
adjustments
z Check TSBs and
OASIS messages for
vehicle concerns
z Carry out quick test
both KOER and KOEO
z Record all codes
1) Did you record any
diagnostic trouble codes? Yes ·
REPAIR all hard diagnostic trouble codes. FOLLOW the
pinpoint tests. REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual first, then this Workshop Manual. No ·
REFER to Diagnosis By Symptom in this section, then GO to
Step 5. 2) Are any continuous test
memory codes present? Yes ·
CLEAR codes and CARRY OUT drive cycle test. No ·
GO to Step 4. 3) Did the continuous test
memory codes reappear? Yes ·
REPAIR all continuous test memory codes. FOLLOW the
pinpoint tests. REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual then the transmission reference
manual, then this workshop manual, then GO to Step 4. No ·
GO to Step 4. 4) Is the concern repaired? Yes ·
CARRY OUT the final quick test to verify that no diagnostic
trouble codes are present. CLEAR memory codes. No ·
REFER to Diagnosis By Symptom in this section.
5) Are there any electrical
concerns? Yes ·
INSTALL the scan tool and CARRY OUT the output state
control test, then GO to Step 6. No ·
REFER to the hydraulic and mechanical routine to diagnose
and REPAIR the concern, then GO to Step 7. 6) Was the transmission
concern corrected when the
scan tool was installed? Yes ·
REFER to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual, intermittent fault diagnosis section and use
the scan tool to diagnose cause of concern in the processor,
vehicle harness or external inputs (sensors or switches). Klj . 1 ba
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No ·
REFER to the hydraulic and mechanical routine to diagnose
the concern, then GO to Step 7. 7) Is the concern repaired? Yes ·
CARRY OUT the final quick test to verify that no diagnostic
trouble codes are present. CLEAR memory codes. No ·
Get assistance from technical hotline. Klj . 2 ba
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DIAGNOSIS AND TESTING
Preliminary Inspection
The following items must be checked prior to beginning the diagnostic procedures:
Know and Understand the Concern
In order to correctly diagnose a concern, first understand the customer complaint or condition.
Customer contact may be required in order to begin to verify the concern. Understand the conditions,
including when the concern occurs. For example:
zHot or cold vehicle temperature
z Hot or cold ambient temperature
z Vehicle driving conditions
z Vehicle loaded/unloaded
After understanding when and how the concern occurs, proceed to Verification of Condition.
Verification of Condition
This section provides information that must be used in both determining the actual cause of customer
concerns and carrying out the appropriate procedures.
The following procedures must be used when verifying customer concerns for the transmission.
Determine Customer Concern
NOTE: Some transmission conditions can cause engine concerns. An electronic pressure control short
circuit can cause engine misfiring. The torque converter clutch not disengaging will stall the engine.
Determine customer concerns relative to vehicle use and dependent driving conditions, paying
attention to the following items:
zHot or cold vehicle operating temperature
z Hot or cold ambient temperatures
z Type of terrain
z Vehicle loaded/unloaded
z City/highway driving
z Upshifting
z Downshift
z Coasting
z Engagement
z Noise/vibration — check for dependencies, either rpm dependent, vehicle speed dependent,
shift dependent, gear dependent, range dependent, or temperature dependent.
Check Fluid Level and Condition
Fluid Level Check SECTION 307-
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CAUTION: The vehicle should not be driven if the fluid level indicator shows the fluid
below the DO NOT DRIVE mark or internal failure could result.
NOTE: If the vehicle has been operated for an extended period, at high highway speeds, in city traffic,
during hot weather, or while pulling a trailer, the fluid needs to cool down to obtain an accurate
reading.
NOTE: The fluid level reading on the indicator will differ from operating and ambient temperatures. The
correct reading should be within the normal operating temperature range.
Under normal circumstances the fluid level should be checked during normal maintenance. If the
transmission starts to slip, shifts slowly, or shows signs of fluid leaking, the fluid level should be
checked.
1. With the transmission in P (PARK), the engine at idle, foot pressed on the brake, move the range selector lever through each gear and allow engagement of each gear. Place the
transmission range selector lever in the P position.
2. Wipe the fluid level indicator cap and remove the indicator.
3. Wipe the indicator with a clean cloth.
4. Install the indicator back in the filler tube until it is fully seated, then remove the indicator. The fluid level should be within the normal operating temperature range.
High Fluid Level
A fluid level that is too high may cause the fluid to become aerated due to the churning action of the
rotating internal parts. This will cause erratic control pressure, foaming, loss of fluid from the vent tube,
and possible transmission failure. If an overfill reading is indicated, drain and refill the transmission.
Low Fluid Level
A low fluid level could result in poor transmission engagement, slipping, or failure. This could also
indicate a leak in one of the transmission seals or gaskets. Adding Fluid Item Description
1 Fluid level at room temperature 10°-
35°C (50°-95°F) 2 Fluid level at operating temperature 66°-
77°C (150°-170°F) 3 Do not drive mark Klj . 2 ba
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CAUTION: The use of any other type of transmission fluid than specified could result in
transmission failure.
If fluid needs to be added, add fluid in 0.25L (1/2 pint) increments through the filler tube. Do not overfill
the fluid. For fluid type, refer to the specification chart.
Fluid Condition Check
1. Check the fluid level.
2. Observe the color and the odor. The color under normal circumstances should be dark reddish, not brown or black or have a burnt odor.
3. Hold the fluid level indicator over a white facial tissue and allow the fluid to drip onto the facial tissue and examine the stain.
4. If evidence of solid material is found, the transmission fluid pan should be removed for further inspection.
5. If the stain is a foamy pink color this may indicate coolant in the transmission. The engine cooling system should also be inspected at this time.
6. If fluid contamination or transmission failure is confirmed by the sediment in the bottom of the fluid pan, the transmission must be disassembled and completely cleaned. This includes the
torque converter and cooler tubes. The oil- to-air cooler will need to be installed.
7. Carry out diagnostic checks and adjustments. Refer to Diagnosis By Symptom in this section. Klj . 3 ba
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DIAGNOSIS AND TESTING
Road Testing Vehicle
NOTE:
Always drive the vehicle in a safe manner according to the driving conditions and obey all
traffic laws.
The shift point road test and torque converter operation tests provide diagnostic information on
transmission shift controls and torque converter operation. SECTION 307-
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DIAGNOSIS AND TESTING
Shift Point Road Test
This test verifies that the shift control system is operating correctly.
1. Bring engine and transmission up to normal operating temperature.
2. Operate vehicle with transmission range selector lever in (D) position.
3. NOTE: Shift speed ranges are approximate for all applications. For specific applications
(engine, axle ratio and application) refer to the Automatic Transmission Specification Issue,
available from Ford Customer Service Division.
Apply minimum throttle and observe speeds at which upshift occurs and torque converter
engages; refer to the 4R70W Shift Speeds chart in this section.
4. With the transmission in Overdrive (fourth gear), press the transmission control switch. The transmission should downshift to third gear. Release the accelerator pedal; engine braking
should occur.
5. Press accelerator pedal to floor, wide open throttle (WOT). Transmission should shift from third to second gear, or third to first, depending on vehicle speed. Torque converter clutch should
disengage and then reapply.
6. With the transmission in (D) position and speed above 80 km/h (50 mph) and less than half throttle, move the transmission range selector lever from (D) position to manual 2 position and
remove pressure from the accelerator pedal. Transmission should immediately downshift into
second gear. With vehicle remaining in manual 2 position, move the transmission range selector
lever into manual 1 position, and release accelerator pedal. Transmission should downshift into
first gear at speeds approximately below 45- 56 km/h (28-35 mph).
7. If transmission fails to upshift/downshift or torque converter clutch does not apply and release, refer to Diagnosis By Symptom in this section.
SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Shift Speeds 4.6L 4V MACH 1 (3.55:1
Axle Ratio)
Throttle Position Shift MPH Km/H
Light throttle 1-
2 10-14 16-23
TP voltage 2-
3 18-22 29-35
1.25 volts 3-
4 34-37 55-60
Closed throttle 4-
3 22-25 35-40
3-2 12-16 19-26
2-1 11-7 18-11
Wide open throttle 1-
2 36-44 58-71
2-3 75-83 121-134
3-2 70 113
2-1 33 53
Shift Speeds 4.6L 2V HO (3:27:1 Axle Klj . 1 ba
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Ratio)
Throttle Position Shift MPH Km/H
Light throttle 1-
2 9-12 14-19
TP voltage 2-
3 14-18 23-29
1.25 volts 3-
4 36-38 58-61
Closed throttle 4-
3 26-22 42-35
3-2 15-11 24-18
2-1 12-8 19-13
Wide open throttle 1-
2 29-44 47-71
2-3 74-80 119-129
3-2 73 117
2-1 32 51
Shift Speeds 3.8L (3:27:1 Axle Ratio) Throttle Position Shift MPH Km/H
Light throttle 1-
2 6-
10 10-16
TP voltage 2-
3 18-22 29-35
1.25 volts 3-
4 28–30 45–48
Closed throttle 4-
3 24-22 39-35
3-2 14-12 22-19
2-1 6-8 10-13
Wide open throttle 1-
2 36-40 58-64
2-3 74-70 119-112
3-2 67 108
2-1 28 45
Shift Speeds 3.8L (3:08:1 Axle Ratio) Throttle Position Shift MPH Km/H
Light throttle 1-
2 6-10 10-16
TP voltage 2-
3 16-20 26-32
1.25 volts 3-
4 38-42 61-68
Closed throttle 4-
3 34-28 55-45
3-2 16-13 26-21
2-1 9-
7 14-
11 Wide open throttle 1-
2 38-45 61-72
2-3 72-76 116-122
3-2 71 114
2-1 31 50 Klj . 2 ba
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