2003 FORD MUSTANG key

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-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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Diagnosing an electronically controlled automatic transmission is simplified by using the following
procedures. One of the most important things to remember is that there is a definite procedure to
follow. DO NOT TAKE 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. By following the diagnostic sequence, the technician will be able to diagnose and repair the
concern the first time.
On-
Board Diagnostics With Diagnostic Tool
NOTE: For detailed instruction and other diagnostic methods using the scan tool, refer to the scan tool
tester manual and the Powertrain Control/Emissions Diagnosis (PC/ED) manual. These quick tests
should be used to diagnose the powertrain control module (PCM) and should be carried out in order.
zQuick Test 1.0 - Visual Inspection
z Quick Test 2.0 - Set Up
z Quick Test 3.0 - Key On, Engine Off (KOEO)
z Quick Test 4.0 - Continuous Memory
z Quick Test 5.0 - Key On, Engine Running (KOER)
„ Special Test Mode
„ Wiggle Test
„ Output Test Mode
„ PCM Reset Mode
„ Clearing DTCs
„ OBD II Drive Cycle
z Other Scan Tool Features
For further information on other diagnostic testing features using the scan tool, refer to the Powertrain
Control/Emissions Diagnosis (PC/ED) manual. Other diagnostic methods include the following:
„Parameter Identification (PID) Access Mode
„ Freeze Frame Data Access Mode and Manual
007-
00131 or equivalent 73 III Automotive Meter
105-
R0057 or equivalent UV Leak Detector Kit
164-
R0756 or equivalent Klj . 2 ba
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z
Repair all vehicle speed DTCs.
z Make sure that the vehicle speed sensor and digital TR sensors are functional.
z Select "Active Command Modes."
z Select "Trans - Bench Mode or Trans - Drive Mode."
OSC — Transmission Bench Modes
The following Transmission Bench Modes may be used or required during diagnostics.
SSA, SSB and TCC in BENCH MODE
The BENCH MODE allows the technician to carry out electrical circuit checks on the following
components:
zSSA - activates SSA OFF or ON.
z SSB - activates SSB OFF or ON.
z Transmission converter clutch (TCC) - activates TCC OFF or ON.
OSC "SSA, SSB, TCC" BENCH MODE operates ONLY when:
zthe digital TR sensor is operational and no digital TR sensor DTCs are present.
z the vehicle speed input is operational and no VSS sensor DTCs are present.
z the transmission range selector lever is in P.
z the key is ON.
z the engine is OFF.
OSC Command Values
zOFF - turns solenoid OFF.
z ON - turns solenoid ON.
z XXX - cancels OSC value sent.
z SEND - sends the values to PCM.
BENCH MODE Procedure for SSA, SSB and TCC
Follow operating instructions from the scan tool menu screen:
zSelect "Output State Control."
z Select "Trans - Bench Mode."
z Select "PIDs" to be monitored.
z Monitor all selected PIDs during test.
z Select "Parameters - SSA, SSB or TCC."
z Select "ON" to turn solenoid ON.
z Press "SEND" to send command ON.
z Select "OFF" to turn solenoid OFF.
z Press "SEND" to send command OFF. Klj . 2 ba
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z
Select "XXX" to cancel at any time.
z Press "SEND."
EPC in BENCH MODE
The BENCH MODE is also used to test the functionality of the transmission's electronic pressure
control. During BENCH MODE, the electronic pressure control (EPC) solenoid can ramp up/down in
increments of 103 kPa (15 psi) from zero to 620 kPa (90 psi) and 620 kPa (90 psi) to zero psi.
The OSC functions for the parameter EPC allows the technician to choose the following options:
zEPC - activates EPC to selected values.
z 00 - sets EPC pressure to 00 kPa (00 psi).
z 15 - sets EPC pressure to 103 kPa (15 psi).
z 30 - sets EPC pressure to 206 kPa (30 psi).
z 45 - sets EPC pressure to 310 kPa (45 psi).
z 60 - sets EPC pressure to 411 kPa (60 psi).
z 75 - sets EPC pressure to 517 kPa (75 psi).
z 90 - sets EPC pressure to 620 kPa (90 psi).
To carry out an EPC BENCH MODE pressure functionality test, install a pressure gauge in the EPC
port. The following requirements are required to carry out this test:
zVSS and digital TR sensor operational
z No VSS and digital TR sensor DTCs
z Transmission range selector lever in P
z Key ON
z Engine ON
z Engine speed at least 1,500 rpm for accurate EPC pressure measurement
To carry out an EPC BENCH MODE solenoid circuit pinpoint test, the following requirements are
required.
zVSS and digital TR sensor operational
z No VSS and digital TR sensor DTCs
z Transmission range selector lever in P
z Key ON
z Engine OFF
OSC Command Values
z00 - sets EPC pressure to 00 kPa (00 psi).
z 15 - sets EPC pressure to 103 kPa (15 psi).
z 30 - sets EPC pressure to 206 kPa (30 psi).
z 45 - sets EPC pressure to 310 kPa (45 psi).
z 60 - sets EPC pressure to 411 kPa (60 psi). Klj . 3 ba
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pressures. The best test for the EPC is to use the BENCH MODE and a hydraulic pressure gauge.
Using EPC in the BENCH MODE will confirm that the EPC is working at both the higher and lower
pressures.
The OSC functions for the parameter EPC allows the technician to choose the following options:
zEPC - activates EPC to selected values
z 00 - sets EPC pressure to 00 kPa (00 psi).
z 15 - sets EPC pressure to 103 kPa (15 psi).
z 30 - sets EPC pressure to 206 kPa (30 psi).
z 45 - sets EPC pressure to 310 kPa (45 psi).
z 60 - sets EPC pressure to 411 kPa (60 psi).
z 75 - sets EPC pressure to 517 kPa (75 psi).
z 90 - sets EPC pressure to 620 kPa (90 psi).
OSC "EPC" DRIVE MODE operates ONLY when:
zthe digital TR sensor is operational and no digital TR sensor DTCs are present.
z the vehicle speed sensor is operational and no VSS sensor DTCs are present.
z the transmission range selector lever is in O/D.
z the pressure gauge is installed.
z the key is ON.
z the engine is ON.
z the vehicle speed is greater than 3.2 km/h (2 mph).
z the OSC value for EPC must be greater than what the PCM commands (see EPC PID).
OSC Command Values
z00 - sets EPC pressure to 00 kPa (00 psi).
z 15 - sets EPC pressure to 103 kPa (15 psi).
z 30 - sets EPC pressure to 206 kPa (30 psi).
z 45 - sets EPC pressure to 310 kPa (45 psi).
z 60 - sets EPC pressure to 411 kPa (60 psi).
z 75 - sets EPC pressure to 517 kPa (75 psi).
z 90 - sets EPC pressure to 620 kPa (90 psi).
z XXX - cancels OSC value sent.
z SEND - sends the values to PCM.
DRIVE MODE Procedure for EPC.
Follow operating instructions from the scan tool menu screen.
zSelect "Output State Control."
z Select "Trans - Drive Mode."
z Select "PIDs" to be monitored. Klj . 7 ba
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NOTE:
Refer to the Transmission Vehicle Harness Connector illustration preceding these
pinpoint tests. A1 ELECTRONIC DIAGNOSTICS
z
Select PARK.
z Key in OFF position.
z Check to make sure the transmission harness connector
is fully seated, pins are fully engaged in connector and
in good condition before proceeding.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link.
z Enter the following diagnostic mode on the diagnostic
tool: PCM.
z Enter the following diagnostic mode on the diagnostic
tool: Active Command Modes.
z Enter the following diagnostic mode on the diagnostic
tool: Output State Control (OSC).
z Enter the following diagnostic mode on the diagnostic
tool: Trans- Bench Mode.
z Does vehicle enter Trans- Bench Mode? Yes
GO to
A2 .
No
REPEAT procedure to enter
Trans-Bench Mode. If vehicle
did not enter Trans- Bench
Mode, REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual for diagnosis
of PCM. A2 WIGGLE TEST
z
Select PIDs to be monitored.
z Select "ON" to turn suspect solenoid on.
z Press "SEND".
z Wiggle all wiring and connectors to the transmission.
Monitor the Solenoid State for changes.
z Select "OFF" to turn solenoid off.
z Press "SEND".
z Does the suspect solenoid(s) fault state change? PID Command PID Actual
SSA SS1F
SSB SS2F
TCC TCCF Yes
REPAIR open or short in the
vehicle harness or connector.
No
GO to
A3 .
A3 SOLENOID FUNCTIONAL CHECK
z
Monitor each solenoid state.
z Turn each solenoid ON and OFF.
z Does the solenoid turn ON and OFF when
commanded and can solenoid activation be heard? Yes
GO to
A4 .
No
GO to A5 .
A4 OSC TRANS-
DRIVE MODE (GR_CM OR TCC) z
Carry out OSC Trans- Drive Mode.
z Select GR_CM for Shift Solenoids or follow procedures
for GR_CM as listed.
z Select TCC for Torque Converter Clutch Solenoid.
Follow procedures of TCC in Drive Mode as listed.
z Does the transmission upshift and downshift or
torque converter engage/disengage when
commanded? Yes
CLEAR all DTCs. ROAD TEST
to verify if concern is still
present. If concern is still
present, REFER to
Diagnosis By Symptom in this section to
diagnose shift or torque
converter concern.
No
GO to A5 .
A5 CHECK FOR BATTERY VOLTAGE
z
Remove transmission fluid pan. Yes Klj . 4 ba
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z
Visually inspect the lead frame and connectors for
damage.
z Key in ON position.
z Measure the voltage with the positive lead to VPWR
solenoid pin and negative lead to a good ground.
z Is the voltage greater than 10 volts? GO to
A6 .
No
CHECK for open or short circuit
in harness, or solenoid. A6 ELECTRICAL SIGNAL CHECK
z
Measure the voltage with the positive lead connected to
VPWR solenoid pin and the negative lead to the signal
pin of the appropriate solenoid.
z Enter the following diagnostic mode on the diagnostic
tool: Trans- Bench Mode.
z Select Parameter SSA, SSB or TCC.
z Select "ON".
z Press "SEND".
z Turn the solenoids ON and OFF, while monitoring the
voltage, solenoid state on the scan tool (ON and OFF),
and listen for the solenoid to activate (click).
z Measure the voltage with the positive lead to VPWR pin
and the negative lead to the TCC pin.
z Enter the following diagnostic mode on the diagnostic
tool: Select Parameter TCC.
z Select "ON".
z Press "SEND".
z Turn the solenoid ON and OFF, while monitoring the
voltage, solenoid state on the scan tool (ON and OFF), Yes
GO to
A7 .
No
CHECK for open or short circuit
in harness, solenoid or a PCM
concern. Klj . 5 ba
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and listen for the solenoid to activate (click).
z Select "OFF", press "SEND".
z Does the voltage and solenoid state change? A7 CHECK LEAD FRAME CONNECTIONS
z
Key in OFF position.
z Disconnect: Lead Frame.
z Inspect for damaged or pushed out pins, corrosion, ect.
z Using the special tool, check each of the lead frame
connector pins.
z Does the special tool go through the lead frame
connector pins? Yes
INSTALL a new lead frame. GO
to
A8 .
No
GO to A8 .
A8 CHECK SOLENOID RESISTANCE AT SOLENOID
z
Key in OFF position.
z Disconnect the appropriate solenoid from the lead
frame.
z Measure the solenoid resistance between the pins of
the solenoid. Yes
GO to
A9 .
No
INSTALL a new solenoid. Klj . 6 ba
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