2007 FORD FIESTA torque

Automatic Transmission/Transaxle -
Vehicles With: 4Speed Automatic
307-01 -33 Transmission (AW81-40) 307-01 -33
DESCRIPTION AND OPERATION
This is influenced by the following variables: Vehicle
speed,
Engine load, Transmission fluid temperature.
Accelerator pedal position, The following are actuated:
Transmission input speed, SSA shift solenoid valve,
Vehicle speed,
Transmission fluid temperature,
Selector lever position.
The
following are actuated:
Main
regulating valve.
Reverse gear safety strategy
SSB shift solenoid valve.
Torque reduction when pulling away
In order to protect the clutches against excessively
high torque when pulling away, the PCM reduces
the engine torque in response to a request from
the transmission
control.
If the accelerator pedal is depressed while the
The transmission control unit prevents shifts into vehicle is pulling away, then the transmission reverse gear while the vehicle is driving forwards, control unit sends a corresponding signal as otherwise serious transmission damage can be requesting a torque reduction via the CAN databus. caused.
The reverse gear safety strategy is active when This
is influenced by the
following variables:
reverse gear is engaged with the selector lever at ' Selector lever position,
vehicle speeds in excess of 11 kmlh. Accelerator pedal position,
In this
case the transmission control unit actuates ' Engine speed,
the shift timing solenoid valve, as a result of which Transmission input speed,
the actuating pressure does not reach the reverse
. Vehicle speed. gear clutch or the reverse gear brake.
The following are actuated:
The reverse gear safety strategy is deactivated
PCM (torque reduction request signal via the
when the vehicle speed is below 9 kmlh. The
actuating pressure can then reach the reverse gear CAN
databus).
clutch and the reverse gear brake and the gearshift
into reverse gear is performed.
Selector lever positions
This is influenced by the following variables:
Vehicle speed,
Selector lever position.
The
following are actuated:
Shift timing solenoid valve.
Selector lever position "P"
No gear is engaged in selector lever position "P".
The parking
pawl is engaged manually via the
selector lever cable and the selector shaft.
Avoidance of gearshift judder during
engagement of a transmission range Selector
lever position "R"
In order to prevent gearshift judder when moving The reverse gear is eWaged in selector lever
the selector lever from N to D, the transmission position "R.
control unit initially shifts into
2nd gear instead of
1 st gear, and then immediately shifts back into I st
gear before the gearshift process is finished. Selector lever position "N"
This reduces the amount of gearshift judder during No gear is engaged in selector lever position WNW. engagement of a forward drive range.
The powertrain is not blocked. This is influenced by the following variables:
Selector lever position,
Accelerator pedal position,
Transmission input speed,
2006.0 Fiesta 1212006 G380530en
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Automatic Transmission/Transaxle -
Vehicles With: 4Speed Automatic
307-01 -35 Transmission (AW81-40) 307-01 -35
DESCRIPTION AND OPERATION
Engine speed
1 The engine speed is detected by the crankshaft
position (CKP) sensor and passed on to the PCM.
The engine speed is transmitted from the PCM via
the CAN
databus to the transmission control unit.
The transmission control unit uses this signal for:
Torque reduction during gearshifts,
Pressure control during gearshifts.
Engine load
The PCM determines a load signal which is
transmitted via the CAN
databus to the
transmission control unit.
The transmission control unit uses this signal for:
Torque reduction during gearshifts,
Pressure control during gearshifts,
Shift timing adaptation during upshifts,
Shift timing adaptation during shifts from 3rd to
4th gear,
Hill climb mode,
( ' Hill descent mode. ' ,
Torque reduction request signal
Before performing a gearshift, the transmission
control unit sends a signal via the CAN
databus to
the PCM requesting a torque reduction.
The PCM then reduces the engine torque, ensuring
that the gearshift is as smooth and judder-free as
possible.
Brake signal
The PCM receives a signal from the stoplamp
switch when the brake pedal is depressed.
This signal is transmitted via the CAN
databus to
the transmission control unit.
The transmission control unit uses this signal for:
Gearshift control,
Engagement of the TCC
Accelerator pedal position
The PCM receives the current accelerator pedal
position signal from the Accelerator Pedal Position
(APP) sensor.
This signal is transmitted via the CAN
databus to
the transmission control unit.
The transmission control unit uses this signal for:
Controlling the main line pressure,
Gearshift control,
Engagement of the TCC,
Shift timing adaptation during upshifts,
Shift timing adaptation during shifts from 3rd to
4th gear,
Shift timing adaptation during shifts from 4th to
3rd gear,
Avoidance of gearshift judder during
engagement of a transmission range,
Torque reduction when pulling away.
Coolant temperature
The coolant temperature is detected by the Engine
Coolant Temperature (ECT) sensor and passed
on to the PCM.
This signal is transmitted via the CAN
databus to
the transmission control unit.
The transmission control unit uses this signal for:
Cold start mode,
Engagement of the TCC
Selector lever position
The transmission control unit transmits the selector
lever position to the instrument cluster.
The instrument cluster uses the signal to send a
request for a warning tone to the GEM when the
selector lever is not in position "P" and the driver's
door is opened.
-
2006.0 Fiesta 1212006 G380530en
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Automatic TransmissionlTransaxle -
Vehicles With: 4-Speed Automatic
307-01 -37 Transmission
(AW81-40) 307-01 -37
DESCRIPTION AND OPERATION
Sensors
OSS sensor
TSS sensor
The TSS sensor is an inductive pickup.
It measures the transmission input speed via the
outer plate carrier of the
3rdl4th gear clutch and
sends the signal to the transmission control unit.
The transmission control unit uses this signal for:
Torque reduction during gearshifts,
Pressure control during gearshifts,
Shift timing adaptation during upshifts,
Shift timing adaptation during shifts from 3rd to
4th gear,
Shift timing adaptation during shifts from 4th to
3rd gear,
Avoidance of gearshift judder during
engagement of a transmission range,
Torque reduction when pulling away.
Consequences of signal failure:
No TCC,
no torque reduction,
no shift timing adaptation,
no 4th gear. The
OSS sensor is a Hall sensor.
It is mechanically connected via a gear to the input
wheel of the differential assembly.
It measures the vehicle speed via the input wheel
of the differential assembly and sends the signal
to the transmission control unit.
The transmission control unit uses this signal for:
Gearshift control,
Engagement of the TCC,
Torque reduction during gearshifts,
Pressure control during gearshifts,
Shift timing adaptation during upshifts,
Shift timing adaptation during shifts from 3rd to
4th gear,
Shift timing adaptation during shifts from 4th to
3rd gear,
Reverse gear safety strategy,
Avoidance of gearshift judder during
engagement of a transmission range,
Torque reduction when pulling away,
Hill climb mode,
Hill descent mode.
2006.0 Fiesta 1212006 G380530en
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Automatic Transmission/Transaxle -
Vehicles With: 4Speed Automatic
307-01 -38 Transmission (AW81-40) 307-01 -38
DESCRIPTION AND OPERATION
Consequences of signal failure:
NoTCC,
no torque reduction, no shift timing adaptation,
no 4th
gear.
TR sensor
The TR sensor serves to signal the currently
selected transmission range to the transmission
control unit.
It is a switch which transmits the selected
transmission range directly to the transmission
control unit.
In addition, the starter inhibit relay is actuated by
the PCM via the TR sensor when the selector lever
is in the positions "P" or
N.
In selector lever position "R the backup lamp relay
is also actuated via the TR sensor.
The transmission control unit uses this signal for:
Controlling the main line pressure,
Gearshift control,
Engagement of the TCC,
Shift timing adaptation during upshifts,
Shift timing adaptation during shifts from 3rd to
4th gear,
Shift timing adaptation during shifts from 4th to
3rd gear,
Reverse gear safety strategy,
Avoidance of gearshift judder during
engagement of a transmission range,
Torque reduction when pulling away.
Consequences of signal failure:
NoTCC,
no shift timing adaptation.
2006.0 Fiesta 1212006 G380530en
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Automatic Transmission/Transaxle -
Vehicles With: 4Speed Automatic
307-01 -46 Transmission
(AW81-40) 307101 -46
DIAGNOSIS AND TESTING
Symptom Possible Sources Action
PO722 Vehicle speed sensor Vehicle speed sensor (VSS).
1 (vSS) circuit no signal I circuit(+
REFER to WDS.
PO740 Torque converter clutch Lock-up duty solenoid.
solenoid failure
I ~ircuit(s).
REFER to WDS.
REFER to WDS.
PO741 Torque converter clutch
1 (TCC) system.
PO742 Torque converter clutch TCC system stuck on.
I circuit(s).
TCC system stuck off.
REFER to WDS.
PO743 Torque converter clutch Lock-up duty solenoid.
solenoid failure
I circuit(s).
REFER to WDS.
REFER to WDS.
PO727 Engine revolution speed
error
PI 746 Pressure control
I solenoid A open circuit
Powertrain control module
(PCM).
Circuit(s).
I
Line pressure control solenoid.
Circuit(s).
REFER to WDS.
PI 747 Pressure control
solenoid
A short circuit
Line pressure control solenoid.
Circuit(s).
REFER to WDS.
PO972 Shift solenoid A
performance Shift solenoid
A open
circuit.
Circuit(s).
Internal mechanical/hydraulic
failure.
REFER to WDS.
REFER to WDS.
PO974 Shift solenoid A elec- Shift solenoid A.
trical I circuit(!+
PO973 Shift solenoid A elec-
trical
REFER to WDS. Shift solenoid A short circuit.
Circuit(s).
PO975 Shift solenoid B
performance Shift solenoid
B.
Circuit(s).
Internal mechanical/hydraulic
failure.
REFER
to WDS.
PO976 Shift solenoid B Shift solenoid B short circuit.
Circuit(s).
REFER to WDS.
PO977 Shift solenoid B Shift solenoid B open circuit.
Circuit(s).
REFER to WDS.
PO787 Timing solenoid elec- Timing solenoid short circuit.
trical I circuit(s).
REFER to WDS.
REFER to WDS. PO788 Timing solenoid elec-
trical
-- - -
Timing solenoid open circuit.
Circuit(s).
REFER to WDS. PO1 15 Engine coolant signal
error Reported engine failure.
REFER to WDS. I PI 71 9 Engine torque signal
error Reported engine failure.
REFER to WDS. PI 783 Transmission over
temperature condition
2006.0 Fiesta 12/2006 G371498en
Temperature sensor failure.
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Automatic Transmission/Transaxle -
Vehicles With: 4-Speed Automatic
307-01 47 Transmission (AW81-40) 307-01 -47
DIAGNOSIS AND TESTING
Symptom Possible Sources Action
'
U2516 CAN bus off transmit
error
I 5750 Throttle open malfunction 1 . CAN bus. 1. REFER to WDS. I
CAN bus.
U1900 CAN Communication
bus fault error
Line Pressure Test
C1750 Accelerator pedal posi-
tion signal malfunction
. CAN bus.
CAUTIONS:
A Carry out the line pressure test before
carrying out the stall speed test.
If line
pressure is low at idle, do not carry out the
stall speed test or further transaxle damage
will occur.
Accelerator pedal position
sensor.
A Do not maintain wide open throttle (WOT)
in any range for more than five seconds.
REFER to WDS.
A After testing each of the following ranges
ID' (DRIVE) and 'R' (REVERSE)r move the 1. Connect the special tools to the line pressure selector lever to 'N' (NEUTRAL) and run
the engine at
I000 rpm for approximately test point.
i, 1 minute to allow the torque converter to 2. Start the engine and check the line pressures.
cool. Refer to the line pressure chart to determine if -- --- line pressure is within specification. N0TE:Make sure that the self test and electrical 3m If the line pressure is not within specification, repairs have been carried out, or test results may
be incorrect. refer to the
line pressure diagnosis chart.
Line Pressure Chart
Range
Idle Stall
R 0.59 - 0.68 5.88 - 6.76 1.58 - 1.83 15.88 - 18.24
Line Pressure Diagnosis Chart
I I Pressure regulator valve sticking. I
Test Results
Higher than specification in 'D' (DRIVE) and 'R'
(REVERSE)
2006.0 Fiesta 1212006 G371498en
Possible Source
Pressure control solenoid inoperative or open wire
harness.
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Automatic TransmissionlTransaxle -
Vehicles With: 4-Speed Automatic
307-01 -48 Transmission (AW81-40) 307-01 -48
DIAGNOSIS AND TESTING
Stall Speed Test
This test checks the operation of the following
components:
1
Test Results
Lower than specification in 'Dl (DRIVE) and 'R'
(REVERSE)
Lower than specification in
'Dl (DRIVE)
Lower than specification in
'R' (REVERSE)
torque converter
forward clutch
low one way clutch assembly
engine performance
Possible Source
Pressure control solenoid inoperative or open wire
harness.
Pressure regulator valve sticking.
Worn oil pump.
Oil strainer blocked.
Fluid leak from each clutch hydraulic circuit.
Drive hydraulic circuit failure.
Forward clutch failure.
Reverse hydraulic circuit failure. Reverse clutch failure.
First and reverse brake failure.
WARNINGS:
A Do not maintain wide open throttle (WOT)
in any range for more than five seconds.
A If the engine speed (rpm) recorded by the
tachometer exceeds maximum specified
rpm, release the accelerator pedal
immediately. Clutch or band slippage is
indicated.
N0TE:The stall speed test should be carried out
with the engine and transaxle at normal operating
temperatures (50°C to 80°C).
A Apply the parking brake firmly while N0TE:Prolonged use of this procedure may set
carrying out each stall test. DTC PO71 2. After carrying out the stall speed test,
A Apply the foot brake firmly while carrying run the OBD test and clear the DTCs.
out each stall test. I. Connect a tachometer to the engine.
CAUTIONS:
A Always carry out the line pressure test
before carrying out the stall speed test. If
the line pressure is low at idle, do not carry
out the stall speed test or further transaxle
damage will occur.
A After testing each of the following ranges
'D'
(DRIVE) and 'R' (REVERSE), move the
selector lever to
'N' (NEUTRAL) and run
the engine at 1000 rpm for approximately
one minute to allow the torque converter
to cool.
2. Press the accelerator pedal to the floor WOT in
each selected range. Record the rpm reached
in each selected range and refer to the stall
speed chart.
3. If the stall speed is not within specification, refer
to the stall speed diagnosis chart.
Stall S~eed Chart
I Engine 1.6L I Speed (rpm) I
I 'Dl (DRIVE) I 2500 2 150 1
'R' (REVERSE) 2420 +, 150 -
Stall
Speed Diagnosis Chart
2006.0 Fiesta 1212006 G371498en
Test Results
Lower than specification in ID' (DRIVE) and 'R'
(REVERSE)
Possible Source
Low engine power.
Torque converter one-way clutch failure.
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Automatic Transmission/Transaxle -
Vehicles With: 4-Speed Automatic
307-01 49 Transmission (AW81-40) 307-01 -49
DIAGNOSIS AND TESTING

Test Results
Higher than specification in 'Dl (DRIVE)
Higher than specification in
'R' (REVERSE)
Lower than specification in 'D' (DRIVE)
Lower than specification in
'R' (REVERSE)
Possible Source
Pressure control solenoid inoperative.
Pressure regulator valve sticking.
Forward clutch failure (slipping).
One-way clutch No.2 failure.
Pressure control solenoid inoperative.
Pressure regulator valve sticking.
Reverse clutch failure (slipping).
First and reverse brake failure (slipping).
Drive hydraulic circuit failure.
Forward clutch failure.
Pressure control solenoid inoperative.
Pressure regulator valve sticking.
Worn oil pump.
Oil strainer blocked.
Fluid leak from each clutch hydraulic circuit.
( Time Lag Test 1. Using a suitable stop watch, measure the time
lag three times and calculate the average time.
Time lag is the time between moving the selector Record the
time lag and refer to the time lag
lever from
IN' (NEUTRAL) to ID' (DRIVE) or IN' chart.
(NEUTRAL) to 'R' (REVERSE). With the parking 2. If the time lag is not within specification, refer
brake applied the vehicle must not move if the
to the time lag diagnosis chart.
selector lever is moved from 'N' (NEUTRAL) to
ID'
(DRIVE) or 'N' (NEUTRAL) to 'R' (REVERSE). Time Lag Chart
Drive is engaged when the vehicle starts to rise.
A WARN1NG:Apply the parking brake firmly IN' (NEUTRAL) to ID' while carrying out each test. 1 (DRIVE)
(NEUTRAL) and run the engine at 1000 rpm
for approximately
1 minute to allow the
torque converter to cool.
less than 1.0 seconds
CAUTI0N:After testing each of the
following ranges
'D' (DRIVE) and 'R'
Range
I Lower than specification in IN' (NEUTRAL) to 'Dl I Pressure control solenoid inoperative.
Ti me
(REVERSE), move the selector lever to 'N'
'N' (NEUTRAL) to 'R'
(REVERSE)
Time Lag Diagnosis Chart
(DRIVE) less
than 1.2 seconds
Test Results
Pressure regulator valve sticking.
Forward clutch failure (slipping).
Possible Source
I Timing solenoid failure.
I I Drive hydraulic circuit failure. I
2006.0 Fiesta IZIZOO~ G371498en
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