2007 FORD FIESTA ECO mode

Automatic TransmissionlTransaxle -
Vehicles With: 4-Speed Automatic
307-01 -31 Transmission (AW81-40) 307-01 -31
DESCRIPTION AND OPERATION
The transmission control unit determines hill climb
mode or trailer operation from the change in throttle
; valve position supplied by the PCM in relation to
the acceleration of the vehicle.
Depending on the driving resistance, the
transmission control unit chooses between two
gearshift maps which have been specially
programmed for this purpose and in which the shift
timings are again chosen as a function of the
accelerator pedal position and the vehicle speed..
Hill descent mode
The hill descent mode is used to take better
advantage of engine braking during hill descents.
A 'hill descent' situation is recognised by the
transmission control unit if the vehicle is
accelerating without operation of the accelerator
pedal.
If in addition the brake is also depressed then the
transmission control unit automatically shifts back
from 4th into 3rd gear.
( ' Cold start mode
In order to reach operating temperature as quickly
as possible under low ambient temperatures,
gearshifts into 4th gear and engagement of the
torque converter clutch (TCC) are suppressed if
one of the following conditions is met:
Transmission fluid temperature below +20 "C
Coolant temperature below - 40°C
The following are actuated: SSA shift solenoid valve,
SSB shift solenoid valve,
Shift solenoid valve, TCC.
Overheating protection mode
The overheating protection mode serves to protect
the transmission against overheating and the
serious damage that this can cause.
If the transmission fluid temperature reaches a
temperature of around 135
"C, the transmission
control employs a shift pattern designed to prevent
a further increase in the transmission fluid
temperature. When
the transmission fluid temperature drops
back below approx. 125
"C, the transmission
control exits the overheating protection mode.
The MIL warning lamp is actuated by the
transmission control unit if the transmission fluid
temperature reaches approximately 140
"C.
The MIL warning lamp goes out again when the
transmission fluid temperature drops back to below
around 130
"C.
Main line pressure control
In order to ensure the highest possible efficiency
of the automatic transmission and to limit the power
losses from the fluid pump, the main line pressure
is adapted accordingly by the main regulating valve
as a function of the accelerator pedal position
(driver torque demand) and the selector lever
position.
This is influenced by the following variables:
Accelerator pedal position and actuation
Selector lever position
The following are actuated:
Main 'regulating valve
Engagement of the TCC
The TCC is engaged in 3rd and 4th gear depending
on the current driving situation.
Engagement is controlled in accordance with the
shift map stored in the control unit.
This is influenced by the following variables:
Accelerator pedal position and actuation,
Vehicle speed,
Selector lever position,
Transmission fluid temperature,
Coolant temperature.
The following are actuated:
Shift solenoid valve, TCC.
Torque reduction during gearshifts
In order to improve the quality of gearshifts and to
avoid gearshift judder, the engine torque is reduced
by the PCM in response to a request from the
transmission control unit during gearshifts.
The engine torque is also reduced during
engagement and disengagement of the TCC.
2006.0 Fiesta 1212006 G380530en
procarmanuals.com

Acceleration Control - 1.3L Duratec-8V
(Rocam)ll.25L Duratec-1 6V (Sigma)ll.4L
31 0-02A-5 Duratec-1 6V (Sigma)/l .6L Duratec-1 6V (Sigma)
31 0-02A-5
DIAGNOSIS AND TESTING
PCM to the electronic throttle body including
the electrical connectors in area "B" (see
system overview).
- There is an obstruction inside the throttle
body bore. Remove the air cleaner outlet pipe
and check for obstructions.
- There is an obstruction inside the electronic
throttle body. Remove the air cleaner outlet
pipe and check that the plate moves freely
against the springs and returns to a slightly
open position. If it does not, install a new
electronic throttle body.
P2176 - Throttle plate adaptation error
- When the ignition is turned off, the throttle
body carries out an adaptation cycle and
spring check. This can be audible after a
short delay (up to 30 seconds) following the ignition key being turned to position
0 and
can be visually observed with the air cleaner
outlet pipe removed. The throttle plate is
moved through a series of positions to check
the TP sensor value and relearn the
electronic throttle body characteristics. If a
concern is detected during this test,
P2176
DTC will be set. If there are already any of
I the other DTCs, the adaptation test could
potentially fail. Therefore the other DTCs
should be resolved first
(e.g. low battery
voltage) and a retest can be carried out by
clearing the DTCs and keying on and off
again. Check the whole area "B" (see system
overview) for any concerns and if no concern
is found, install a new electronic throttle body.
P2100 - H bridge error
- A fault has been detected on the circuit
connecting the electronic throttle body motor
and the PCM. Check for any other
non-electronic accelerator control related
DTCs and rectify them first. Check area "B"
(see system overview) and if no failure is
found, install a new PCM.
PCM Related Codes
The PCM continuously monitors all the sensors. It
also checks that the monitor is functioning as
expected. If there is a fault with the monitor, the
following DTCs will be set.
P2107 - Processor monitoring on the main
controller fault.
P2108 -Analogue to digital converter
- Inferred intake mass air flow lower than
expected
- Engine speed monitor ratio error
- Pedal ratio monitor error
- TP sensor ratio monitor error
- Fault in torque generation
- Fault present in engine speed limitation
Multiple sensor faults can make the PCM assume
that there is a monitor fault. If other DTCs exist,
rectify these first. These DTCs indicate a failure in
area
"A or "B" and they are also related to the
manifold absolute pressure and temperature
(MAPT) sensor and the crankshaft position (CKP)
sensor. If no other failures are found, install a new
PCM.
Indirect Codes
There are two brake pedal switches located under
the brake pedal. Check that both of these are
connected and functioning correctly. A brake pedal
switch concern will only cause the "EAC FAIL"
message to be displayed, it will not lead to a limited
performance mode. Follow WDS instructions.
PO571 - Brake switch error
If the voltage to the accelerator pedal and the
electronic throttle body cannot be regulated
correctly, the components may not operate as
expected. Therefore it is important to detect if there
is a concern in the supply voltage
PO641 - Sensor voltage supply circuit I noisy
signal
PO642 - Sensor voltage supply circuit 1 short
to ground or open circuit
PO643 - Sensor voltage supply circuit 1 short
to battery
PO651 - Sensor voltage supply circuit 2 noisy
signal
PO652 - Sensor voltage supply circuit 2 short
to ground or open circuit
2006.0 Fiesta 1212006 G356253en
procarmanuals.com