Opel Frontera UE. Manual - part 856

6E1–307

X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

Engine Control Module (ECM)

The engine control module (ECM) is located in the
passenger compartment below the center console. The
ECM controls the following:

Fuel metering system.

Ignition timing.

On–board diagnostics for powertrain functions.

The ECM constantly observes the information from
various sensors. The ECM controls the systems that
affect vehicle performance. The ECM performs the
diagnostic function of the system. It can recognize
operational problems, alert the driver through the Check
Engine lamp, and store diagnostic trouble codes (DTCs).
DTCs identify the problem areas to aid the technician in
making repairs.

014RX002

ECM Function

The ECM supplies either 5 or 12 volts to power various
sensors or switches. The power is supplied through
resistors in the ECM which are so high in value that a test
light will not light when connected to the circuit. In some
cases, even an ordinary shop voltmeter will not give an
accurate reading because its resistance is too low.
Therefore, a digital voltmeter with at least 10 meg

input

impedance is required to ensure accurate voltage
readings. Tool J 39200 meets this requirement.
The ECM controls output circuits such as the injectors,
IAC, cooling fan relays, etc., by controlling the ground or
the power feed circuit through transistors or through
either of the following two devices:

Output Driver Module (ODM)

Quad Driver Module (QDM)

ECM Components

The ECM is designed to maintain exhaust emission levels
to government mandated standards while providing
excellent driveability and fuel efficiency. The ECM
monitors numerous engine and vehicle functions via
electronic sensors such as the throttle position (TP)
sensor, heated oxygen sensor (HO2S), and vehicle

speed sensor (VSS). The ECM also controls certain
engine operations through the following:

Fuel injector control

Ignition control module

Evaporative emission (EVAP) purge

A/C clutch control

ECM Voltage Description

The ECM supplies a buffered voltage to various switches
and sensors. It can do this because resistors in the ECM
which are so high in value that a test light may not
illuminate when connected to the circuit. An ordinary shop
voltmeter may not give an accurate reading because the
voltmeter input impedance is too low. Use a 10–megohm
input impedance digital voltmeter (such as J 39200) to
assure accurate voltage readings.
The input/output devices in the ECM include
analog–to–digital converters, signal buffers, counters,
and special drivers. The ECM controls most components
with electronic switches which complete a ground circuit
when turned ON. These switches are arranged in groups
of 4 and 7, called either a quad driver module (QDM),
which can independently control up to 4 output terminals,
or Output Driver Module (ODM) which can independently
control up to 7 outputs. Not all outputs are always used.

ECM Inputs/Outputs

Inputs – Operating Conditions Read

Air Conditioning Compressor Clutch ON or OFF

Engine Coolant Temperature

Crankshaft Position

Exhaust Oxygen Content

Manifold Absolute Pressure

Battery Voltage

Throttle Position

Fuel Tank Vapor Pressure

Fuel Tank Level

Exhaust Gas Recirculation (EGR) Feedback

Knock

Vehicle Speed

Fuel Pump Voltage

Power Steering Pressure

Intake Air Temperature

Camshaft Position

Outputs – Systems Controlled

EVAP Canister Purge Solenoid

Exhaust Gas Recirculation (EGR)

Ignition Control

Fuel Injector Control

Idle Air Control

Coolant Fan Relays

Electric Fuel Pump Relay Compressor Clutch Relay

Air Conditioning

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X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

Diagnostics
– OBD II Malfunction Indicator Lamp (Check Engine

lamp)

– Data Link Connector (DLC)
– Data Output

Tachometer Signal

ECM Service Precautions

The ECM is designed to withstand normal current draws
associated with vehicle operation. Avoid over loading any
circuit. When testing for opens and shorts, do not ground
or apply voltage to any of the ECM’s circuits unless
instructed to do so. These circuits should only be tested
using digital voltmeter J 39200. The ECM should remain
connected to the ECM or to a recommended breakout
box.

014RX002

Throttle Position (TP) Sensor

The throttle position (TP) sensor is a potentiometer
connected to the throttle shaft on the throttle body. The
ECM monitors the voltage on the signal line and
calculates throttle position. As the throttle valve angle is
changed (accelerator pedal moved), the TP sensor signal
also changes. At a closed throttle position, the output of
the TP sensor is about 0.25 volts. As the throttle valve
opens, the output increases so that at wide open throttle
(WOT), the output voltage should be about 4.75 volts.
The ECM calculates fuel delivery based on throttle valve
angle (driver demand). A broken or loose TP sensor may
cause intermittent bursts of fuel from an injector and
unstable idle because the ECM thinks the throttle is
moving. A hard failure in the TP sensor 5–volt reference
or signal circuits will set either a DTC P0122 or DTC
P0123. A hard failure with the TP sensor ground circuit
may set DTC P0123 and DTC P0122. Once a DTC is set,
the ECM will use an artificial default value based on
engine RPM and mass air flow for the throttle position,
and some vehicle performance will return. A high idle may
result when either DTC P0122 or DTC P0123 is set. The
ECM can detect intermittent TP sensor faults.

101RX003

Transmission Range Switch

IMPORTANT:

The vehicle should not be driven with the

transmission range switch disconnected; idle quality will
be affected.
The four inputs from the transmission range switch
indicate to the ECM which position is selected by the
transmission selector lever. This information is used for
ignition timing, EVAP canister purge, EGR and IAC valve
operation.
For more information on the transmission range switch,
refer to 4L30–E Automatic Transmission.

Vehicle Speed Sensor (VSS)

The ECM determines the speed of the vehicle by
converting a pulsing voltage signal from the vehicle speed
sensor (VSS) into miles per hour. The ECM uses this
signal to operate the speedometer.

0008

Use of Circuit Testing Tools

Do not use a test light to diagnose the powertrain
electrical systems unless specifically instructed by the

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X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

diagnostic procedures. Use Connector Test Adapter Kit J
35616 whenever diagnostic procedures call for probing
connectors.

Aftermarket Electrical And Vacuum
Equipment

Aftermarket (add–on) electrical and vacuum equipment is
defined as any equipment which connects to the vehicle’s
electrical or vacuum systems that is installed on a vehicle
after it leaves the factory. No allowances have been made
in the vehicle design for this type of equipment.

NOTE: No add–on vacuum equipment should be added
to this vehicle.

NOTE: Add–on electrical equipment must only be
connected to the vehicle’s electrical system at the battery
(power and ground).
Add–on electrical equipment, even when installed to
these guidelines, may still cause the powertrain system to
malfunction. This may also include equipment not
connected to the vehicle electrical system such as
portable telephones and radios. Therefore, the first step
in diagnosing any powertrain problem is to eliminate all
aftermarket electrical equipment from the vehicle. After
this is done, if the problem still exists, it may be diagnosed
in the normal manner.

Electrostatic Discharge Damage

Electronic components used in the ECM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused by
electrostatic discharge. Less than 100 volts of static
electricity can cause damage to some electronic
components. By comparison, it takes as much as 4000
volts for a person to feel even the zap of a static
discharge.
There are several ways for a person to become statically
charged. The most common methods of charging are by
friction and induction.

An example of charging by friction is a person sliding
across a vehicle seat.

Charge by induction occurs when a person with
well–insulated shoes stands near a highly charged
object and momentarily touches ground. Charges of
the same polarity are drained off leaving the person
highly charged with the opposite polarity. Static
charges can cause damage, therefore it is important
to use care when handling and testing electronic
components.

TS23793

NOTE: To prevent possible electrostatic discharge
damage, follow these guidelines:

Do not touch the ECM connector pins or soldered
components on the ECM circuit board.

Do not touch any electronic sensor module
component leads.

Do not open the replacement part package until the
part is ready to be installed.

Before removing the part from the package, ground
the package to a known good ground on the vehicle.

If the part has been handled while sliding across the
seat, while sitting down from a standing position, or
while walking a distance, touch a known good ground
before installing the part.

GENERAL DESCRIPTION — AIR
INDUCTION

Air Induction System

The air induction system filters contaminants from the
outside air, and directs the progress of the air as it is
drawn into the engine. A remote–mounted air cleaner
prevents dirt and debris in the air from entering the
engine. The air duct assembly routes filtered air to the
throttle body. Air enters the engine by the following steps:

1. Through the throttle body.
2. Into the intake manifold.
3. Through the cylinder head intake ports.
4. Into the cylinders.

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X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION

028RX002

GENERAL DESCRIPTION — FUEL
METERING

Acceleration Mode

The ECM provides extra fuel when it detects a rapid
increase in the throttle position and the air flow.

Accelerator Controls

The accelerator control system is a cable–type system
with specific linkage adjustments.
Refer to Cable Adjustment.

Battery Voltage Correction Mode

When battery voltage is low, the ECM will compensate for
the weak spark by increasing the following:

The amount of fuel delivered.

The idle RPM.

CMP Signal

The ECM uses the camshaft position (CMP) sensor
signal to determine the position of the number 1 piston
during its power stroke, allowing the ECM to calculate
true sequential multiport fuel injection (SFI). Loss of this
signal will set a DTC P0341 or DTC P0342. If the CMP
signal is lost while the engine is running, the fuel injection
system will shift to a calculated sequential fuel injection
based on the last fuel injection pulse, and the engine will
continue to run. The engine can be restarted and will run
in the calculated sequential mode with the fault is present,
with a 1–in–4 chance of being correct.

Clear Flood Mode

Clear a flooded engine by pushing the accelerator pedal
down all the way. The ECM then de–energizes the fuel
injectors. The ECM holds the fuel injectors de–energized
as long as the throttle remains above 80% and the engine
speed is below 800 RPM. If the throttle position becomes
less than 80%, the ECM again begins to pulse the
injectors ON and OFF, allowing fuel into the cylinders.

Deceleration Fuel Cutoff (DFCO) Mode

The ECM reduces the amount of fuel injected when it
detects a decrease in the throttle position and the air flow.
When deceleration is very fast, the ECM may cut off fuel
completely for short periods.

Engine Speed/Vehicle Speed/ Fuel Disable
Mode

The ECM monitors engine speed. It turns off the fuel
injectors when the engine speed increases above 6000
RPM. The fuel injectors are turned back on when engine
speed decreases below 5750 RPM.

Fuel Cutoff Mode

No fuel is delivered by the fuel injectors when the ignition
is OFF. This prevents engine run–on. In addition, the
ECM suspends fuel delivery if no reference pulses are
detected (engine not running) to prevent engine flooding.

Fuel Injector

The sequential multiport fuel injection (SFI) fuel injector is
a solenoid–operated device controlled by the ECM. The
ECM energizes the solenoid, which opens a valve to allow
fuel delivery.
The fuel is injected under pressure in a conical spray
pattern at the opening of the intake valve. Excess fuel not
used by the injectors passes through the fuel pressure
regulator before being returned to the fuel tank.
A fuel injector which is stuck partly open will cause a loss
of fuel pressure after engine shut down, causing long
crank times.

0003

Fuel Metering System Components

The fuel metering system is made up of the following
parts:

The fuel injectors.

The throttle body.

The fuel rail.

The fuel pressure regulator.

The ECM.

The crankshaft position (CKP) sensor.

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