1F–4 ENGINE CONTROLS
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
IGNITION SYSTEM OPERATION
This ignition system does not use a conventional distrib-
utor and coil. It uses a crankshaft position sensor input
to the Engine Control Module (ECM). The ECM then de-
termines Electronic Spark Timing (EST) and triggers the
electronic ignition system ignition coil.
This type of distributorless ignition system uses a “waste
spark’’ method of spark distribution. Each cylinder is in-
dividural with coil per cylinder.
These systems use the EST signal from the ECM to
control the EST. The ECM uses the following informa-
tion:
Engine load (manifold pressure or vacuum).
Atmospheric (barometric) pressure.
Engine temperature.
Intake air temperature.
Crankshaft position.
Engine speed (rpm).
ELECTRONIC IGNITION SYSTEM
IGNITION COIL
The Electronic Ignition (EI) system ignition coil is
mounted near on the cylinder head.
A terminals of the EI system ignition coil provides the
spark for each spark plug. The EI system ignition coil is
not serviceable and must be replaced as an assembly.
CRANKSHAFT POSITION SENSOR
This Electronic Ignition (EI) system uses a magnetic
crankshaft position sensor. This sensor protrudes
through its mount to within approximately 1.3 mm (0.05
inch) of the crankshaft reluctor. The reluctor is a special
wheel attached to the crankshaft with 58 slots machined
into it, 57 of which are equally spaced in 6-degree inter-
vals. The last slot is wider and serves to generate a
“sync pulse.” As the crankshaft rotates, the slots in the
reluctor change the magnetic field of the sensor, creat-
ing an induced voltage pulse. The longer pulse of the
58th slot identifies a specific orientation of the crank-
shaft and allows the Engine Control Module (ECM) to
determine the crankshaft orientation at all times. The
ECM uses this information to generate timed ignition
and injection pulses that it sends to the ignition coils and
to the fuel injectors.
CAMSHAFT POSITION SENSOR
The Camshaft Position (CMP) sensor sends a CMP sig-
nal to the Engine Control Module (ECM). The ECM uses
this signal as a “sync pulse” to trigger the injectors in the
proper sequence. The ECM uses the CMP signal to indi-
cate the position of the #1 piston during its power stroke.
This allows the ECM to calculate true sequential fuel in-jection mode of operation. If the ECM detects an incor-
rect CMP signal while the engine is running, Diagnostic
Trouble Code (DTC) P0341 will set. If the CMP signal is
lost while the engine is running, the fuel injection system
will shift to a calculated sequential fuel injection mode
based on the last fuel injection pulse, and the engine will
continue to run. As long as the fault is present, the en-
gine can be restarted. It will run in the calculated se-
quential mode with a 1-in-6 chance of the injector
sequence being correct.
IDLE AIR SYSTEM OPERATION
The idle air system operation is controlled by the base
idle setting of the throttle body and the Idle Air Control
(IAC) valve.
The Engine Control Module (ECM) uses the IAC valve to
set the idle speed dependent on conditions. The ECM
uses information from various inputs, such as coolant
temperature, manifold vacuum, etc., for the effective
control of the idle speed.
FUEL CONTROL SYSTEM
OPERATION
The function of the fuel metering system is to deliver the
correct amount of fuel to the engine under all operating
conditions. The fuel is delivered to the engine by the in-
dividual fuel injectors mounted into the intake manifold
near each cylinder.
The main fuel control sensors are the Manifold Absolute
Pressure (MAP) sensor, the oxygen sensor (O2S), and
the heated oxygen sensor (HO2S).
The MAP sensor measures or senses the intake man-
ifold vacuum. Under high fuel demands, the MAP sensor
reads a low vacuum condition, such as wide open
throttle. The Engine Control Module (ECM) uses this in-
formation to enrich the mixture, thus increasing the fuel
injector on-time, to provide the correct amount of fuel.
When decelerating, the vacuum increases. This vacuum
change is sensed by the MAP sensor and read by the
ECM, which then decreases the fuel injector on-time
due to the low fuel demand conditions.
The O2S is located in the exhaust manifold. The HO2S
is located in the exhaust pipe. The oxygen sensors indi-
cate to the ECM the amount of oxygen in the exhaust
gas, and the ECM changes the air/fuel ratio to the en-
gine by controlling the fuel injectors. The best air/fuel ra-
tio to minimize exhaust emissions is 14.7:1, which
allows the catalytic converter to operate most efficiently.
Because of the constant measuring and adjusting of the
air/fuel ratio, the fuel injection system is called a “closed
loop” system.
The ECM uses voltage inputs from several sensors to
determine how much fuel to provide to the engine. The
1F–10 ENGINE CONTROLS
DAEWOO M-150 BL2
fuels use alcohol to increase the octane rating of the
fuel. Although alcohol-enhanced fuels may raise the oc-
tane rating, the fuel’s ability to turn into vapor in cold
temperatures deteriorates. This may affect the starting
ability and cold driveability of the engine.
Low fuel levels can lead to fuel starvation, lean engine
operation, and eventually engine misfire.
Non-OEM Parts
The EOBD system has been calibrated to run with Origi-
nal Equipment Manufacturer (OEM) parts. Something
as simple as a high performance-exhaust system that
affects exhaust system back pressure could potentially
interfere with the operation of the Electric Exhaust Gas
Recirculation (EEGR) valve and thereby turn on the
MIL. Small leaks in the exhaust system near the heated
oxygen sensor (HO2S) can also cause the MIL to turn
on.
Aftermarket electronics, such as cellular phones, ster-
eos, and anti-theft devices, may radiate Electromagnet-
ic Interference (EMI) into the control system if they are
improperly installed. This may cause a false sensor
reading and turn on the MIL.
Environment
Temporary environmental conditions, such as localized
flooding, will have an effect on the vehicle ignition sys-
tem. If the ignition system is rain-soaked, it can tempo-
rarily cause engine misfire and turn on the MIL.
Vehicle Marshaling
The transportation of new vehicles from the assembly
plant to the dealership can involve as many as 60 key
cycles within 2 to 3 miles of driving. This type of opera-
tion contributes to the fuel fouling of the spark plugs and
will turn on the MIL with a set DTC P0300.
Poor Vehicle Maintenance
The sensitivity of the EOBD will cause the MIL to turn on
if the vehicle is not maintained properly. Restricted air fil-
ters, fuel filters, and crankcase deposits due to lack of oil
changes or improper oil viscosity can trigger actual ve-
hicle faults that were not previously monitored prior to
EOBD. Poor vehicle maintenance can not be classified
as a “non-vehicle fault,” but with the sensitivity of the
EOBD, vehicle maintenance schedules must be more
closely followed.
Severe Vibration
The Misfire diagnostic measures small changes in the
rotational speed of the crankshaft. Severe driveline
vibrations in the vehicle, such as caused by an exces-
sive amount of mud on the wheels, can have the same
effect on crankshaft speed as misfire and, therefore,
may set DTC P0300.
Related System Faults
Many of the EOBD system diagnostics will not run if the
Engine Control Module (ECM) detects a fault on a re-
lated system or component. One example would be thatif the ECM detected a Misfire fault, the diagnostics on
the catalytic converter would be suspended until the
Misfire fault was repaired. If the Misfire fault is severe
enough, the catalytic converter can be damaged due to
overheating and will never set a Catalyst DTC until the
Misfire fault is repaired and the Catalyst diagnostic is al-
lowed to run to completion. If this happens, the custom-
er may have to make two trips to the dealership in order
to repair the vehicle.
SERIAL DATA COMMUNICATIONS
Keyword 2000 Serial Data
Communications
Government regulations require that all vehicle
manufacturers establish a common communication sys-
tem. This vehicle utilizes the “Keyword 2000” commu-
nication system. Each bit of information can have one of
two lengths: long or short. This allows vehicle wiring to
be reduced by transmitting and receiving multiple sig-
nals over a single wire. The messages carried on Key-
word 2000 data streams are also prioritized. If two
messages attempt to establish communications on the
data line at the same time, only the message with higher
priority will continue. The device with the lower priority
message must wait. The most significant result of this
regulation is that it provides scan tool manufacturers
with the capability to access data from any make or
model vehicle that is sold.
The data displayed on the other scan tool will appear the
same, with some exceptions. Some scan tools will only
be able to display certain vehicle parameters as values
that are a coded representation of the true or actual val-
ue. On this vehicle, the scan tool displays the actual val-
ues for vehicle parameters. It will not be necessary to
perform any conversions from coded values to actual
values.
EURO ON-BOARD DIAGNOSTIC
(EOBD)
Euro On-Board Diagnostic Tests
A diagnostic test is a series of steps, the result of which
is a pass or fail reported to the diagnostic executive.
When a diagnostic test reports a pass result, the diag-
nostic executive records the following data:
The diagnostic test has been completed since the last
ignition cycle.
The diagnostic test has passed during the current
ignition cycle.
The fault identified by the diagnostic test is not cur-
rently active.
When a diagnostic test reports a fail result, the diagnos-
tic executive records the following data:
The diagnostic test has been completed since the last
ignition cycle.
ENGINE CONTROLS 1F–135
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0300 MULTIPLE CYLINDER MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is
misfiring. The ECM looks for a quick drop in crankshaft
speed. This test is executed in blocks of 100 engine rev-
olution tests. It may take between one to several tests to
store a Diagnostic Trouble Code (DTC) and illuminate
the Malfunction Indicator Lamp (MIL). Under light misfire
conditions, it may also take more than one trip to set a
DTC. Severe misfire will flash the MIL, indicating that
catalyst damage is possible.
Conditions for Setting the DTC
Emission threshold is 3.0% for manual transaxle.
20 engine cycles have occurred since cranking has
started.
A/C compressor clutch has not just engaged or disen-
gaged.
Engine load and engine speed are in a detectable re-
gion and are at or above zero torque.
Camshaft Position (CMP) sensor is in synchroniza-
tion.
Electric Exhaust Gas Recirculation (EEGR) flow
diagnostic is not in progress.
Fuel level is greater than or equal to 20% of rated
tank capacity.
Decel Fuel Cutoff (DFCO) not active.
Fuel is not shutoff from high engine speed of 6500
rpm for manual transaxle vehicle.
Fuel is not shutoff at 255 km/h (158 mph).
Throttle position change is less than 3% per 125 ms.
Vehicle has not encountered an abusive engine
speed of 7000 rpm.Crankshaft speed patters are normal.
Throttle position is less than 4% when vehicle speed
is greater than 10 km/h (6 mph).
Engine speed is between 800 and 4500 rpm.
Vehicle voltage is between 11 and 16 volts.
Engine Coolant Temperature (ECT) is between –7°C
(20°F) and 120°C (248°F).
The engine speed is less than or equal to 1800 rpm or
the crank angle sensing error has not been learned.
There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
DTCs P0106, P0107, P0108, P0117, P0118, P0122,
P0123, P0320, P0337, P0341, P0342 and P0502 are
not set.
Action Taken when the DTC Sets
The malfunction Indicator Lamp (MIL) will blinking.
The ECM will record operating conditions at the time
the diagnostic fails. The information will be stored in
the Freeze Frame and failure records buffers.
A history DTC is stored.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An intermittent can also be the result of a defective re-
luctor wheel. Remove the CKP sensor and inspect the
reluctor wheel through the sensor mount hole. Check for
porosity and the condition of wheel. If the DTC is inter-
mittent refer to “Symptoms Diagnosis” in this section.
DTC P0300 – Multiple Cylinder Misfire
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Turn the ignition ON, with the engine OFF.
3. Request Diagnostic Trouble Codes (DTCs)
Are DTCs P0201, P0202, P0203, P0204 set?
–Go to
Applicable DTC
table
Go to Step 3
3
Perform a visual/physical inspection.
Make any repairs that are necessary.
Is the repair complete?–
Go to Step 27Go to Step 4
4Start the engine and allow it to idle.
Are any Misfire Current counters incrementing?–
Go to Step 5Go to Step 6
5Are all counters equal (within a percentage of each
other)?–Go to Step 7Go to Step 11
ENGINE CONTROLS 1F–139
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0300 MULTIPLE CYLINDER MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is
misfiring. The ECM looks for a quick drop in crankshaft
speed. This test is executed in blocks of 100 engine rev-
olution tests. It may take between one to several tests to
store a Diagnostic Trouble Code (DTC) and illuminate
the Malfunction Indicator Lamp (MIL). Under light misfire
conditions, it may also take more than one trip to set a
DTC. Severe misfire will flash the MIL, indicating that
catalyst damage is possible.
Conditions for Setting the DTC
Emission threshold is 3.0% for automatic transaxle
and 3.0% for manual transaxle.
20 engine cycles have occurred since cranking has
started.
A/C compressor clutch has not just engaged or disen-
gaged.
Engine load and engine speed are in a detectable re-
gion and are at or above zero torque.
Camshaft Position (CMP) sensor is in synchroniza-
tion.
Electric Exhaust Gas Recirculation (EEGR) flow
diagnostic is not in progress.
Fuel level is greater than or equal to 20% of rated
tank capacity.
Decel Fuel Cutoff (DFCO) not active.
Fuel is not shutoff from high engine speed of 6500
rpm for manual transaxle vehicle or 6500 rpm in drive
and 6250 rpm in park for automatic transaxle ve-
hicles.
Fuel is not shutoff at 255 km/h (158 mph).
An automatic transmission is not shifting.
Throttle position change is less than 3% per 125 ms.
Vehicle has not encountered an abusive engine
speed of 7000 rpm.
Crankshaft speed patters are normal.Throttle position is less than 4% when vehicle speed
is greater than 10 km/h (6 mph).
Engine speed is between 600 and 4500 rpm.
Vehicle voltage is between 11 and 16 volts.
Engine Coolant Temperature (ECT) is between –7°C
(20°F) and 120°C (248°F).
The engine speed is less than or equal to 1800 rpm or
the crank angle sensing error has not been learned.
There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
DTCs P0106, P0107, P0108, P0117, P0118, P0122,
P0123, P0320, P0337, P0341, P0342 and P0502 are
not set.
Action Taken when the DTC Sets
Emission related.
“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective re-
luctor wheel. Remove the CKP sensor and inspect the
reluctor wheel through the sensor mount hole. Check for
porosity and the condition of wheel. If the DTC is inter-
mittent refer to “Symptoms Diagnosis” in this section.
DTC P0300 – Multiple Cylinder Misfire
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Turn the ignition ON, with the engine OFF.
3. Request Diagnostic Trouble Codes (DTCs)
Are DTCs P0201, P0202, P0203, P0204 set?
–Go to
Applicable DTC
table
Go to Step 3
1F–166 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F210
DIAGNOSTIC TROUBLE CODE (DTC) – P1382 ROUGH ROAD DATA INVALID
(NON ABS)
Circuit Description
The VR sensor is used to detecting the road situation.
By sensing difference of wheel rotation duration caused
by bumps or potholes in the road, the Engine Control
Module (ECM) can determine if the changes in crank-
shaft speed are due to engine misfire or are driveline in-
duced. If the VR sensor detects a rough road condition,
the ECM misfire detection diagnostic will be de-acti-
vated.
The VR sensor is located in front–right wheel.
Conditions for Setting the DTC
Vehicle speed is higher than 10km/h(6.21mph).
No Vehicle Speed Sensor error not set.
VR sensor output signal is higher than 0.26.VR sensor output signal is not change for 30seconds.
Action Taken When The DTCs Sets
The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for more than 10
seconds.
1F–170 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F220
DIAGNOSTIC TROUBLE CODE (DTC) – P1382 ROUGH ROAD DATA INVALID
(ABS)
Circuit Description
The wheel speed sensor is used to detecting the road
situation.
As the wheel is rotated, the wheel speed sensor pro-
duces an AC voltage that increase with wheel speed.
The EBCM uses the frequency of the AC signal to calcu-
late wheel speed. The wheel speed sensor is connected
to EBCM by a “twisted pair” of wires. Twisting reduces
noise susceptibility than may cause a DTC to se.If the
wheel speed sensor detects a rough road condition, the
ECM misfire detection diagnostic will be de-activated.
Conditions for Setting the DTC
Vehicle speed is higher than 10km/h(6.21mph).
No Vehicle Speed Sensor error not set.
VR sensor output signal is higher than 0.26.VR sensor output signal is not change for 30seconds.
Action Taken When the DTC Sets
The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for more than 10
seconds.
1F–174 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F210
DIAGNOSTIC TROUBLE CODE (DTC) – P1385 ROUGH ROAD SENSOR CIRCUIT
FAULT (NON ABS)
Circuit Description
The VR sensor is used to detecting the road situation.
By sensing difference of wheel rotation duration caused
by bumps or potholes in the road, the Engine Control
Module (ECM) can determine if the changes in crank-
shaft speed are due to engine misfire or are driveline in-
duced. If the VR sensor detects a rough road condition,
the ECM misfire detection diagnostic will be de-acti-
vated.
Conditions for Setting the DTC
Vehicle speed is higher than 10km/h(6.21mph).
No Vehicle Speed Sensor error not set.
VR sensor output signal is higher than 0.26.
VR sensor output signal is not change for 30 sec-
onds.Action Taken When The DTCs Sets
The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for more than 10
seconds.
1F–178 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F220
DIAGNOSTIC TROUBLE CODE (DTC) – P1385 ROUGH ROAD SENSOR CIRCUIT
FAULT (ABS)
Circuit Description
The wheel speed sensor is used to detecting the road
situation.
As the wheel is rotated, the wheel speed sensor pro-
duces an AC voltage that increase with wheel speed.
The EBCM uses the frequency of the AC signal to calcu-
late wheel speed. The wheel speed sensor is connected
to EBCM by a “twisted pair” of wires. Twisting reduces
noise susceptibility than may cause a DTC to se.If the
wheel speed sensor detects a rough road condition, the
ECM misfire detection diagnostic will be de-activated.
Conditions for Setting the DTC
Vehicle speed is higher than 10km/h(6.21mph).
No Vehicle Speed Sensor error not set.
VR sensor output signal is higher than 0.26.VR sensor output signal is not change for 30seconds.
Action Taken When The DTCs Sets
The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for more than 10
seconds.