check engine FORD MUSTANG 2003 Workshop Manual

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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DIAGNOSIS AND TESTING
Output State Control (OSC) Mode
Output State Control (OSC) allows the technician to take control of certain parameters to function the
transmission. For example, OSC allows the technician to shift the transmission only when he/she
commands a gear change. If the technician commands 1st gear in OSC, the transmission will remain
in 1st gear until the technician commands the next gear. Another example, the technician can
command a shift solenoid to turn on or off when carrying out an electrical circuit check. OSC has two
modes of operation for transmission, the BENCH MODE and the DRIVE MODE. Each
mode/parameter has a unique set of vehicle operating requirements that the technician is required to
meet before being allowed to operate OSC.
NOTE:
To operate OSC the digital transmission range (TR) sensor must be operational. No Diagnostic
Trouble Codes (DTCs) related to the digital TR sensor can be present.
To operate OSC the vehicle speed source must be operational. No diagnostic codes (DTCs) related to
this source can be present. The vehicle speed source can vary depending on vehicle configuration.
Technicians should verify which input source is applicable for their vehicle application. The following
are potential vehicle speed sources:
„anti- lock braking system (ABS)
„ output shaft speed (OSS) sensor
„ vehicle speed sensor
z The vehicle requirements MUST BE MET when SENDING the OSC value. Refer to individual
test modes for vehicle requirements.
z If the vehicle requirements are NOT MET when SENDING the OSC value, an ERROR
MESSAGE will appear. When the ERROR MESSAGE is received, OSC is aborted and must be
restarted.
z If AFTER SENDING an OSC value, and the vehicle requirements are no longer met, the PCM
will cancel the OSC value and NO ERROR message will appear. Once the vehicle requirements
are met again, the PCM will automatically SEND the previous OSC value without any additional
actions required by the service technician.
z The OSC value XXX may be sent anytime to cancel OSC.
Output State Control (OSC) Procedures
zCarry out visual inspection and vehicle preparation as required.
z Select "Vehicle and Engine Selection" menu.
z Select appropriate vehicle and engine.
z Select "Diagnostic Data Link."
z Select "Powertrain Control Module."
z Select "Output Test Mode."
z Select "KOEO On- Demand Self Test and KOER On- Demand Self Tests."
z Carry out test and record DTCs.
z Repair all NON- Transmission DTCs.
z Repair all digital TR Sensor DTCs.
SECTION 307-
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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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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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*
PCM output driver EPC solenoid is
checked. An error
will be noted if
tolerance is
exceeded. maximum EPC
pressure, harsh
engagements and
shifts. Test D .
P1747
* EPC, wiring,
PCM EPC solenoid
circuit failure,
shorted circuit
or output
driver Voltage through
EPC solenoid is
checked. An error
will be noted if
tolerance is
exceeded. Short circuit causes
minimum EPC
pressure (minimum
capacity) and limits
engine torque
(alternate firm). Go To Pinpoint
Test D .
P1760 EPC, wiring,
PCM EPC solenoid
circuit failure,
shorted circuit
or output
driver PCM detected a
loss of EPC during
operation. Unexpected
reduction in engine
torque. Go To Pinpoint
Test D .
P0750
a SSA, wiring,
PCM SSA solenoid
circuit failure SSA circuit failed
to provide voltage
drop across
solenoid. Circuit
open or shorted or
PCM driver failure
during on-
board
diagnostic. Incorrect gear
selection depending
on condition mode
and manual lever
position. See
Solenoid On/Off
Chart. Go To Pinpoint
Test A .
P0753 SSA, wiring,
PCM SSA electrical
circuit failure SSA circuit fails to
provide voltage
drop across
solenoid. Circuit
open or shorted or
PCM driver failure
during on-
board
diagnostic. Incorrect gear
depending on
condition mode and
manual lever
position. See
Solenoid Off/On
Chart. Flashing
Transmission
Control Indicator
Lamp (TCIL). Go To Pinpoint
Test A .
P0751 SSA, wiring,
PCM Shift solenoid
A functional
failure Mechanical or
hydraulic failure of
the shift solenoid. Incorrect gear
selection depending
on failure mode
manual lever
position. REFER to Solenoid
Operation Chart.
Go To Pinpoint
Test A .
P0781
b SSA or
internal parts 1-
2 shift error Engine rpm drop
not detected when
1-
2 shift was
commanded by
PCM. Incorrect gear
selection depending
on failure or mode
and manual lever
position. Shift errors
may also be due to
other internal
transmission
concerns (stuck
valves, damaged
friction material). REFER to Solenoid
Operation Chart.
Go To Pinpoint
Test A .
P1714 SSA,
internal
components SSA
malfunction Mechanical failure
of the solenoid
detected. Incorrect gear
selection depending
on condition, mode
and manual lever
position. See
Solenoid Operation
Chart. Go To Pinpoint
Test F .
P0755
a SSB, wiring,
PCM SSB solenoid
circuit failure SSB circuit fails to
provide voltage Incorrect gear
selection depending Go To Pinpoint
Test A . Klj . 4 ba
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a
Output circuit check, generated only by electrical symptoms.
b May also be generated by some other non- electric transmission hardware system.
Rotunda Transmission Tester
The Transmission Tester is used to diagnosis the digital transmission range sensor and is used in
conjunction with the pinpoint tests. The tests should be carried out in order. Installing the Transmission
Tester allows separation of the vehicle electronics from transmission electronics; refer to the
Transmission Tester manual for these tests.
zDigital Transmission Range (TR) Sensor Testing components converter
clutch
engagement
error (engine speed
surge) across the
torque converter
clutch. present in 3rd gear.
P1742 TCC,
internal
components TCC solenoid
failed ON TCC solenoid has
failed on by
electric,
mechanical or
hydraulic concern. Harsh shifts. Go To Pinpoint
Test A .
P1743 TCC,
internal
components TCC solenoid
failed ON TCC solenoid has
failed ON by
electric,
mechanical or
hydraulic concern. Harsh shifts. Go To Pinpoint
Test A .
P1744 TCC TCC The PCM picked
up an excessive
amount of TCC
slippage during
normal vehicle
operation. TCC
slippage/erratic or
no torque converter
clutch operation. GO to Diagnosis by
Symptom.
P1767 TCC TCC solenoid
circuit failure
during OBD
Test TCC solenoid
circuit fails to
provide voltage
drop across
solenoid. Circuit
open or shorted or
PCM Driver failure
during OBD Test. Short circuit: engine
stalls in second
(O/D, 2 range) at
low idle speeds with
brake applied.
Open circuit:
Torque Converter
never engages. Go To Pinpoint
Test A .
P1780 TCS TCS not
changing
states TCS not cycled
during self-
test.
TCS circuit open
or shorted. Rerun on-
board
diagnostic and
cycle switch. No
OD cancel when
switch is cycled. REFER to the
Powertrain
Control/Emissions
Diagnosis (PC/ED)
manual.
— TCIL TCIL circuit
failure TCIL circuit open
or shorted. Failed on, OD
cancel mode on. No
flashing TCIL for
EPC failure or
sensor. Failed off,
OD cancel mode
never indicated. No
flashing TCIL for
EPC sensor failure. REFER to the
Powertrain
Control/Emissions
Diagnosis (PC/ED)
manual
P1709 PNP switch PNP switch
out of self-
test
range Vehicle not in
PARK or
NEUTRAL during
on-
board
diagnostic. Rerun on-
board
diagnostic in PARK
or NEUTRAL. Go To Pinpoint
Test C . Klj . 7 ba
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z
Measure the resistance for each solenoid (SSA, SSB or
TCC) as follows:
z Are the resistances correct? Solenoid Resistance (ohms)
SSA 20-
30 SSB 20-
30 TCC 10-
16 A9 CHECK SOLENOID FOR SHORT TO GROUND
z
Check for continuity between engine ground and
appropriate solenoid pin with ohmmeter or other low
current tester. Connection should show infinite
resistance (no continuity).
z Is there continuity? Solenoid Terminal
SSA +/-
SSB +/-
TCC +/- Yes
INSTALL a new solenoid.
No
REFER to
Diagnosis By Symptom in this section for
diagnosis of shift or torque
converter concerns. Klj . 7 ba
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harness is wiggled, the sensor is tapped, or the
vehicle driven?
C6 CHECK DIGITAL TRANSMISSION RANGE SENSOR
OPERATION z
Disconnect: Digital TR Sensor .
z CAUTION: Do not pry on connector. This will
damage the connector and result in a transmission
concern.
z Connect: TR- E Cable to Transmission Tester.
z Connect: TR- E Cable to Digital TR Sensor.
z Place the Digital TR Overlay onto Transmission Tester.
z Carry out Sensor Test as instructed on the Digital TR
Overlay.
z Does the status lamp on the tester TRS- E cable
match the selected gear positions? Yes
Concern is not in the digital TR
sensor, GO to
C7 .
No
INSTALL a new digital TR
sensor. CLEAR DTCs and
REPEAT OBD Tests. C7 CHECK PCM HARNESS CIRCUITS FOR OPENS
z
Key in OFF position.
z Disconnect: Powertrain Control Module (PCM) .
z Inspect for damaged or pushed- out pins, corrosion or
loose wires.
z Disconnect: Digital TR Sensor.
z CAUTION: Do not pry the connector. This will
damage the connector and result in a transmission
concern.
z Disconnect the digital TR sensor connector.
z Install the EEC- V Control System Breakout Box.
z Measure the resistance between the PCM test pin 91 at
the EEC- V Control System Breakout Box and signal
return circuit pin 2 at digital TR sensor connector
harness side.
z For vehicles equipped with a 4.6L engine measure the
resistance between the PCM test pin 34 at the EEC- V
Control System Breakout Box and TR1 circuit pin 4 at
digital TR sensor connector harness side.
z For vehicles equipped with a 3.8L engine measure the
resistance between the PCM test pin 3 at the EEC- V Yes
GO to
C8 .
No
REPAIR open circuit(s).
RECONNECT all components.
CLEAR DTCs. REPEAT OBD
Tests. Klj . 11 ba
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97, 51, 77, 103, and 91 at the EEC-
V Control System
Breakout Box and chassis ground.
z Are all resistances greater than 10,000 ohms? C9 CHECK FOR SHORT BETWEEN TR/PCM INPUT
SIGNAL CIRCUITS z
For vehicles equipped with a 3.8L engine measure the
resistance between test pin 3 and pins 49, 50, and 64 at
the EEC- V Control System Breakout Box.
z For vehicles equipped with a 4.6L engine measure the
resistance between test pin 34 and pins 49, 50, and 64
at the EEC- V Control System Breakout Box.
z For vehicles equipped with a 3.8L engine measure the
resistance between test pin 49 and pins 3, 50, and 64 at
the EEC- V Control System Breakout Box.
z For vehicles equipped with a 4.6L engine measure the Yes
INSTALL a new PCM. REFER
to Section 303
- 14 .
RECONNECT all components.
CLEAR DTCs. REPEAT OBD
Tests.
No
REPAIR shorts on circuits
having less than 10,000 ohms
between other TR/PCM input
signal circuits. RECONNECT
all components. CLEAR DTCs.
REPEAT OBD Tests. Klj . 15 ba
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XXX.
z Press "SEND".
z Does the voltage and solenoid state change? D5 CHECK LEAD FRAME CONNECTIONS
z
Key in OFF position.
z Disconnect: Lead Frame.
z Inspect for damaged or pushed out pins, corrosion, etc.
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
D6 .
No
GO to D6 .
D6 CHECK SOLENOID RESISTANCE AT SOLENOID
z
Disconnect: Transmission Harness .
z Measure the resistance between the pins of the solenoid.
z Measure the resistance of the EPC solenoid.
z Is the resistance between 2.48 and 5.66 ohms? Yes
GO to
D7 .
No
INSTALL a new solenoid.
CLEAR the DTCs. REPEAT
the OBD Tests. D7 CHECK SOLENOID FOR SHORT TO GROUND
z
Check for continuity between engine GROUND and the
EPC solenoid terminals with ohmmeter or other low
current tester (less than 200 milliamps). Connection
should show infinite resistance (no continuity).
z Is there continuity? Yes
INSTALL a new solenoid.
CLEAR the DTCs. REPEAT
the OBD Tests.
No
REFER to
Diagnosis By Symptom in this section for
diagnosis of pressure
concerns. Klj . 19 ba
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