2007 FORD FIESTA Workshop Manual

303-1 4-1 3 Electronic Engine Controls 303-1 4-1 3
DESCRIPTION AND OPERATION
The BPP switch is connected to the instrument
When the brake pedal is pressed again the engine
cluster via a CAN bus. In its rest state the switch
speed drops to idle speed. When the brake pedal
is closed and sends a ground signal to the PCM.
returns to its rest position the engine speed is
The signal from the BPP switch is used in the event increased again.
of failure of the APP sensor for the emergency
operating mode.
Accelerator pedal position (APP) sensor
The PCM requires the pedal position from the APP
sensor in order to regulate the power output of the
engine according to the driver request for power.
The APP sensor is a double contact-less inductive
sensor.
If a concern occurs with the APP sensor while
driving, a diagnostic trouble code
(DTC) is stored
in the PCM.
If both sensors of the APP sensor fail, the engine
is regulated to a maximum engine speed of up to
4000 revlmin after a single operation of the BPP
switch and the stop lamp switch and a subsequent
comparative plausibility test. The vehicle can only
be accelerated to a maximum speed of
56 kmlh.
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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.
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303-1 4-1 5 Electronic Engine Controls 303-1 4-1 5
DIAGNOSIS AND TESTING
Monitors
The purpose of the monitors is to continuously
check the operation of the emission related sensors
and actuators. It then establishes if they are
operating within specified tolerances. All monitors
carry out their functions in such a way as to be
unnoticeable by the driver of the vehicle. Each one
is carried out under specific conditions of load,
speed and engine temperature. The Comprehensive Component Monitor, Combustion
Misfire Monitor and
AirIFuel Ratio Monitor operate
continuously. The remaining monitors are only
invoked under certain operating conditions. On
diesel variants, all of the monitors operate under
normal driving conditions: There are no monitors
which intervene and cause special operating
modes to enable the monitors to work. Some diesel
monitors are non-continuous. This means that in
a drive cycle, monitoring is done as and when
suitable driving conditions exist and potential faults
are accumulated and compared with acceptance
criteria. Examples of this type are the turbocharger
boost pressure and exhaust gas recirculation
(EGR) monitors on vehicles with common rail fuel
injection.
( Comprehensive Component Monitor (CCM)
When the CCM detects a component operating out
of tolerance, it sets a Diagnostic Trouble Code
(DTC), which is stored in the EEPROM. If the same
concern is confirmed during the next trip the MIL
will be switched on. The CCM monitors many
components, sub-systems and signals. The
following is a list of those that can effect emissions
depending on application:
Electronic Ignition (El) System.
Crankshaft Position (CKP) Sensor.
Ignition Coil.
Electronic Throttle Control Unit.
Camshaft Position (CMP) Sensor.
Air Conditioning
(AIC) Clutch.
Idle Air Control (IAC) Valve.
Mass Air Flow (MAF) Sensor.
Manifold Absolute Pressure (MAP) Sensor.
Intake Air Temperature (IAT) Sensor.
Engine Coolant Temperature (ECT) Sensor.
Cylinder Head Temperature (CHT) Sensor.
Heated Oxygen Sensor
(H02S).
Catalyst Monitor Sensor.
Charge Air Temperature Sensor.
Knock Sensor (KS).
Throttle Position (TP) Sensor.
Vehicle Speed Sensor (VSS).
Boost Pressure Sensor.
Cam-Crank Phasing Sensor.
EEPROM.
High Pressure Fuel Injection Pump.
Exhaust Gas Recirculation (EGR) Valve Monitor.
Fuel Injectors.
Turbocharger.
Combustion Noise Monitor.
Barometric Pressure (BARO) Sensor.
Combustion Misfire Monitor (All except vehicles
with diesel engine)
The combustion misfire monitor operates independently of the others, and can detect misfires
caused by the ignition system, fuel system or
mechanical engine components. As each cylinder
fires, a characteristic crankshaft acceleration is
produced. The monitor detects irregularities in the
acceleration pattern using the crankshaft position (CKP) sensor, thus detecting the misfire. It can
also detect which cylinder has misfired.
Combustion misfires can be categorized as follows:
Type
A: These can cause catalytic converter
damage due to excessive internal temperatures.
If a certain number of misfires occur over a
pre-determined number of engine revolutions, the
MIL will be switched on to alert the driver of the
concern.
Type B: These can lead to an increase in emissions
to a point above the EOBD threshold. If the misfire
is detected during a second trip, over a,
pre-determined number of engine revolutions, the
MIL will be switched on. If the misfire does not
occur over the next three trips, the MIL will be
extinguished
AirIFuel Ratio (AFR) Monitor (All except vehicles
with diesel engine)
The H02S fitted before the catalytic converter
(upstream) measures the oxygen content of the
exhaust gas and the variations in it. This then
enables the PCM to adjust the opening times of
the fuel injectors to maintain the correct AFR. This
is known as Short Term Fuel Trim (STFT). If the
same variation is registered a pre-determined
number of times, a permanent correction factor is
applied. This is known as Long Term Fuel Trim
(LTFT), which is stored in the EEPROM. When the
correction factors exceed pre-determined limits a
DTC will be set in the EEPROM. If a concern is
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Electronic Engine Controls
DIAGNOSIS AND TESTING
detected in either the STFT or LTFT, and it is still
present on a second trip, the MIL will be switched
on.
Heated Oxygen Sensor (H02S) Monitor (All except
vehicles with diesel engine)
This monitors the operation of the pre (upstream)
and post (downstream) catalytic converter
H02S
sensors. It will detect deviations in airlfuel ratios
(AFR) and sensor faults.
The
H02S will cause emission increase when its
response time increases too much. To diagnose
a sensor a period is measured and the number of
leanlrich transitions are counted. The sum of valid
periods is then calculated. To avoid
non-representative measurements, the period is
valid only if the
H02S has been below a low
threshold and above a high threshold between 2
consecutive leanlrich transitions.
A failure is
declared when the sum of the measured periods
exceeds the sum of the corresponding limit (held
within the PCM) and the MIL is illuminated.
Catalytic Converter Efficiency Monitor (All except
vehicles with diesel engine)
The efficiency of a catalytic converter is measured
by its ability to store and later release oxygen to
convert harmful gases. The efficiency is reduced
if the converter becomes contaminated as it ages,
and at high gas flow rates, because the exhaust
gas does not remain in the converter long enough
to complete the conversion process. switches
over or until the end of a delay. If this
delay expires or the sensor does not switch, the
sensor is treated as failed.
Combustion Noise Monitor (Vehicles with common
rail fuel injection)
In diesel variants, the Combustion Noise Monitor
is used to trim the fuel injection pulse lengths. Each
fuel injector has an associated set of correction
data that is determined during a production end of
line test. The Combustion Noise Monitor is used
to determine how the fuel injector characteristic
changes from this initial calibration over the life of
the fuel injector.
EGR Monitor (Vehicles with diesel engine)
The functionality of the EGR system is checked by
comparing either the MAP sensor output or EGR
valve lift potentiometer output (depending upon
application) with expected values.
Diagnostic Requirements
Vehicles equipped with EOBD, can be diagnosed
using the WDS. In order for the EOBD system to
be invoked, a number of criteria must be met. After
any repair, which could affect emissions, a trip must
be carried out on the vehicle, to make sure that
engine management system operates correctly.
Malfunction Indicator Lamp (MIL)
The MIL is located in the instrument cluster and is
fitted to alert the driver to the fact that an abnormal
This monitor checks for the oxygen storage condition
has developed in the engine management
capacity (OSC) of the catalytic converter. During system,
that is having an adverse effect on
a controlled period, the catalyst monitor sensor emissions.
In cases of misfires which are likely to
signal is analyzed to evaluate the OSC of the cause
catalytic converter damage, it is switched
catalyst. It represents the quantity of oxygen that on immediately.
With all other faults it will illuminate
is really used for the oxidation-reduction reaction continuously
from the second trip after the condition
by the catalytic converter If a fault has occurred occurred.
Under normal operation it should
with the catalyst monitor sensor during the catalyst illuminate
at key-on and go out almost as soon as
diagnosis, a sensor diagnosis is carried out. During the
engine is started.
the controlled diagnosis phase, the catalyst monitor
Diagnostic Trouble Codes (DTCs) sensor activity is measured and is compared to the
OSC of the catalyst. If this activity is high (low The
DTCs given
by the PCM are standardized,
0SC)theMILwillbeilluminated.Ifthroughoutthe whichmeansthatgenericscantoolscanread
controlled phase, repeated several times, the results from
all vehicles.
downstream sensor output has not moved, the
closed loop mode is delayed in order to test the
sensor. If the catalyst monitor sensor is set to rich,
the injection time is forced to lean and conversely
if the downstream sensor is set to lean, the
injection time is forced to rich until the sensor
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303-1 4-1 7 Electronic Engine Controls 303-1 4-1 7
DIAGNOSIS AND TESTING
The DTC is always a 5 digit alphanumerical
code, for example
"POI 00".
The first digit of a code (letter) identifies the
system which has set the code. Provision has
been made for a total of four systems to be
identified although only the
'PI code is required
for EOBD.
- 'B' for the body
- 'C' for the chassis
- 'P' for the powertrain
- 'U' for the network communications systems
All of the
"xOxxxW codes are standardized codes.
However, any manufacturer can use additional
codes over and above the standardized codes.
These will be labelled
"xlxxx"
The third digit of a code (numeric) identifies the
sub-system which has set the code.
- 'Pxlxx' for metering of fuel and air supply
- 'Px2xx' for metering of fuel and air supply
- 'Px3xx' for ignition system - combustion
misfires
- 'Px4xx' for auxiliary emission control
equipment
- 'Px5xx' for vehicle speed, idle setting and
other related inputs
- 'Px6xx' for trip computer and other related
outputs
- 'Px7xx' for transmission.
- 'Px8xx' for transmission.
- 'Px9xx' category to be determined
- 'PxOxx' category to be determined
When a concern occurs, the actions taken
include storage of the relevant information and
actuation of the MIL occurs in line with the
relevant legislation.
MIL Code List
I PO030 I Heated oxygen sensor (H02S) heater open circuit I
! '
-1 H02S heater low voltage I
I PO032 I H02S heater high voltage I
MILCode
PO036 1- ' Catalyst monitor sensor heater open circuit I
Description
PO037
I PO054 I Catalyst monitor sensor heater resistance out of limits I
Catalyst monitor sensor heater low voltage
PO038
PO053
I PO106 I Manifold absolute pressure (MAP) sensor plausibility malfunction I
-
Catalyst monitor sensor heater high voltage
H02S heater resistance out of limits
I PO107 I MAP sensor circuit low input I
PO108
PO1 09 MAP sensor
circuit high input
MAP sensor temporary malfunction
PO1 12
PO113
I PO117 I ECT circuit low input I
Intake air temperature (IAT) circuit low input
IAT circuit high input
I
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PO114
PO1 16
PO118
IAT intermittent failure
Engine coolant temperature (ECT) signal stuck at low level
ECT circuit high input
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303-1 4-1 8 Electronic Engine Controls 303-1 4-1 8
DIAGNOSIS AND TESTING
I PO123 I TP sensor circuit I high input I
MIL Code
PO119
PO 1 22
I PO130 I H02S circuit open circuit I
Description
ECT intermittent failure
Throttle position
(TP) sensor circuit 1 low input
I PO131 I H02S circuit low voltage I
pol34 r- HO~S IOW amplitude I
PO1 32
PO1 33
I PO136 I Catalyst monitor sensor circuit open circuit I
H02S circuit high voltage
H02S circuit slow response
I PO137 I Catalyst monitor sensor circuit low voltage I
PO1 38
PO1 39
I PO172 I Fuel system error, rich limit I
Catalyst monitor sensor circuit high voltage
Catalyst monitor sensor circuit slow response
PO171
PO171
Fuel system error, lean limit
Fuel system error
, NOx emissions
PO172
PO201
I PO203 I Cylinder No. 3 - injector circuit open circuit I
Fuel system error, HClCO emissions
Cylinder No.
I - injector circuit open circuit
PO202
I PO204 I Cylinder No. 4 - injector circuit open circuit I
Cylinder No. 2 - injector circuit open circuit
-1 TP sensor circuit 2 low input I
1 PO223 1 TP sensor circuit 2 high input I
I PO231 I Fuel pump input low voltage I
PO232
PO261
Fuel pump input high voltage
Cylinder No.
1 - injector circuit low voltage
PO262
PO264
1 PO267 1 Cylinder No. 3 - injector circuit low voltage I
Cylinder No. 1 - injector circuit high voltage
Cylinder No.
2 - injector circuit low voltage
PO265
1 PO268 1 Cylinder No. 3 - injector circuit high voltage I
-- -
Cylinder No. 2 - injector circuit high voltage I
I . PO270 I Cylinder No. 4 - injector circuit low voltage I
PO271
PO300
Cylinder No. 4 - injector circuit high voltage
Random misfire detected
PO301
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Cylinder No. 1 misfire detected
PO302
-- -
Cylinder No. 2 misfire detected
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Electronic Engine Controls
DIAGNOSIS AND TESTING
I PO304 I Cylinder No. 4 misfire detected I
/ I
KS implausible signal I
MIL Code
PO303
PO31 5
PO324
1 PO335 1 Crankshaft position (CKP) sensor implausible signal I
Description
Cylinder No. 3 misfire detected
Flywheel segment adaptation at the Limit
Knock sensor (KS) communication error or implausible signal
1 PO336 1 CKP sensor missing teeth I
1 PO336 1 CKP sensor loss of synchronization I
1 PO336 1 CKP sensor no signal I
I PO340 I Camshaft position (CMP) sensor no signal I
I PO341 I CMP sensor implausible signal I
I PO351 I Ignition coil A primary malfunction I
1 PO352 1 Ignition coil B primary malfunction I
I PO420 I Catalyst system efficiency below threshold I
1 PO444 1 Evaporative mission canister purge valve open circuit I
1 PO458 1 Evaporative mission canister purge valve low voltage I
I '1 PO459 1 Evaporative mission canister purge valve high voltage I
I PO460 I Fuel tank level malfunction from instrument cluster I
-3 I VSS signal too high I
PO500
PO500
Vehicle speed sensor (VSS) signal malfunction
Vehicle speed via CAN (VS CAN) implausible signal
PO51 1
PO560
I PO603 I Powertrain control module (PCM) error NVMY or EEPROM error 1
Idle air control (IAC) valve circuit malfunction
Battery system voltage malfunction high voltage
PO562
PO571
I PO604 I PCM error RAM error I
Battery system voltage malfunction open circuit
Brake switch plausibility error
PO605 I PCM error checksum error I
I PO610 I VID block checksum not correct or not programmed I
I PO617 I Starter relay malfunction I
I PO620 I Generator circuit malfunction I
1 PO628 1 Fuel pump primary circuit low voltage I
I
7 1 Fuel pump primary circuit high voltage I
2006.0 Fiesta 1212006 G384566en
PO625
PO626
Generator low voltage
Generator high voltage
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303-1 4-20 Electronic Engine Controls 303-1 4-20
DIAGNOSIS AND TESTING
1 PO643 1 Transmission sensor power supply 1 high voltage I
MIL Code
PO641
PO642
1 PO646 1 Air conditioning (NC) clutch relay circuit low voltage I
1 PO647 1 NC clutch relay circuit high voltage I
Description
Transmission sensor power supply 1 noisy signal
Transmission sensor power supply
I low voltage
I PO651 I Transmission sensor power supply 2 noisy signal I
i
PO652
PO653
Transmission sensor power supply 2 low voltage
Transmission sensor power supply
2 high voltage
PO654
PO686
1 PO692 1 Cooling fan 1 control circuit high voltage I
Engine run output circuit malfunction
Main relay malfunction low voltage
PO687
PO691
1 PO693 1 Cooling fan 2 control circuit low voltage I
Main relay malfunction high voltage
Cooling fan
1 control circuit low voltage
1 PO694 1 Cooling fan 2 control circuit high voltage I
I PI500 I Vehicle speed sensor (VSS) output circuit malfunction I
PO704
PI 000
Generator command malfunction I
Clutch switch implausible signal
EOBD system readiness test not complete
I P2107 I Safety failure level 3 I
PI 794
P2100
I P2108 I Safety failure level 2 error I
Battery voltage malfunction too high or too low
Engine throttle body H-bridge malfunction
APP sensor circuit 1 high input I
P2119
P2122
1 P2127 1 APP sensor circuit 2 low input I
Engine throttle body throttle flap malfunction
Accelerator pedal position (APP) sensor circuit
1 low input
1 P2128 1 APP sensor circuit 2 high input I
1 P2176 1 Engine throttle body adaptive algorithm failed 1
P2128
P2135
APP sensor circuits I and 2 plausibility error
TP sensor circuits 1 and 2 plausibility error
I UOOOl I Control Area Network (CAN) bus-off or mute I
P2280
P2282
I UOlOl I CAN missing frame from TCU I
Air cleaner obstruction or leakage
Air leakage between throttle and inlet valves
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