2007 FORD FIESTA display

303-1 4-1 4 Electronic Engine Controls 303-1 4-1 4
DIAGNOSIS AND TESTING
Electronic Engine Controls
General Equipment
I Worldwide Diagnostic system (WDS)
Principles of Operation
For Principles of Operation on the electronic
accelerator control system
REFER to: Acceleration Control (31
0-02A,
Diagnosis and Testing).
European On-Board Diagnostics (EOBD)
EOBD is a diagnostic system integrated into the
powertrain control module (PCM). This system
continuously monitors vehicle emission
components. The system includes a malfunction
indicator lamp (MIL) which indicates when there is
a concern that can affect emissions or the system
malfunctions. Data stored within the module DTC
memory can be accessed using a generic scan
tool or WDS.
EOBD is mandated within European Union
regulations from the year 2000 for passenger
vehicles with petrol engines and from 2003 onwards for passenger vehicles with diesel
engines.
EOBD Functions:
Establishes when and how emissions control
faults must be indicated.
Actuates emission control malfunction indicator
lamp (MIL) and fault memory.
Indicates operating conditions in which the
concern occurred (freeze frame data).
Standardized output of operating data such as
engine speed, engine coolant temperature etc.
Standardized names and abbreviations for
components and systems.
Standardized
DTCs for all manufacturers.
Standardized communication with the diagnostic
equipment.
Standardized 16-pin data link connector (DLC)
in area of the instrument panel.
Concern display must be possible using a
generic scan tool.
EOBD consists of the following elements:
Warm-up Cycle C'
The warm-up cycle is an operation that consists of
key on, engine start and a coolant temperature
increase of
22"C, exceeding 71 OC on completion.
Drive Cycle
A drive cycle commences when the engine is
started (cold or warm) and ends when the engine
is switched off.
Trip
A trip begins when the engine is started and is
complete when all the EOBD monitors have
completed a self-test. This may take place over a
number of drive cycles. On diesel variants, the
information gathered from one drive cycle is not
carried over to a subsequent cycle or cycles.
When a concern has been rectified, particularly
after electronic engine control components have
been changed, the DTC memory, which is part of
the EEPROM must be cleared of all trouble codes.
When the DTC memory has been cleared, the code
.
PI000 (known as the readiness code) is set in the
PCM memory, which indicates that since the
EEPROM has been cleared, not all of the
monitoring systems have completed their tests.
PI000 can only be cleared by carrying out a trip,
which includes driving the vehicle under variable
conditions of speed, load and time so that all of the
monitors are completed. As
PI000 will not
illuminate the MIL it is not necessary to carry out
the trip before returning the vehicle to the customer.
Freeze Frame Data
When a concern is detected, various data is stored
depending on application including:
Diagnostic trouble code.
Vehicle speed.
Engine coolant temperature.
Engine speed.
Engine load.
Mixture formation trim value (trim value for
engine wear) (All except vehicles with diesel
engine).
State of oxygen sensor control (open and closed
loop) (All except vehicles with diesel engine).
Distance covered since the concern was first
registered.
2006.0 Fiesta 1212006 G384566en
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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
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