check engine DAEWOO MATIZ 2003 Service Owner's Guide

ENGINE CONTROLS 1F–9
DAEWOO M-150 BL2
appropriate wiring diagram. Refer to “ECM Wiring Dia-
grams” in this Section.
9591
Terminal 49GroundOpen
STRATEGY-BASED DIAGNOSTICS
Strategy-Based Diagnostics
The strategy-based diagnostic is a uniform approach to
repair all Electrical/Electronic (E/E) systems. The diag-
nostic flow can always be used to resolve an E/E system
problem and is a starting point when repairs are neces-
sary. The following steps will instruct the technician on
how to proceed with a diagnosis:
Verify the customer complaint. To verify the customer
complaint, the technician should know the normal op-
eration of the system.

Perform preliminary checks as follows:

Conduct a thorough visual inspection.

Review the service history.

Detect unusual sounds or odors.

Gather Diagnostic Trouble Code (DTC) information to
achieve an effective repair.

Check bulletins and other service information. This
includes videos, newsletters, etc.

Refer to service information (manual) system
check(s).

Refer to service diagnostics.
No Trouble Found
This condition exists when the vehicle is found to oper-
ate normally. The condition described by the customer
may be normal. Verify the customer complaint against
another vehicle that is operating normally. The condition
may be intermittent. Verify the complaint under the con-
ditions described by the customer before releasing the
vehicle.
Re-examine the complaints.
When the complaints cannot be successfully found or
isolated, a re-evaluation is necessary. The complaint
should be re-verified and could be intermittent as de-
fined in “intermittents,” or could be normal.
After isolating the cause, the repairs should be made.
Validate for proper operation and verify that the symp-
tom has been corrected. This may involve road testing
or other methods to verify that the complaint has re-
solved under following conditions:

Conditions noted by the customer.

If a DTC was diagnosed, verify the repair be duplicat-
ing conditions present when the DTC was set as
noted in Failure Records or Freeze Frame data.
Verifying Vehicle Repair
Verification of the vehicle repair will be more compre-
hensive for vehicles with Euro On-Board Diagnostic
(EOBD) system diagnostics. Following a repair, the
technician should perform the following steps:
Important: Follow the steps below when you verify re-
pairs on EOBD systems. Failure to follow these steps
could result in unnecessary repairs.

Review and record the Failure Records and the
Freeze Frame data for the DTC which has been diag-
nosed (Freeze Fame data will only be stored for an A,
B and E type diagnostic and only if the Malfunction
Indicator Lamp has been requested).

Clear the DTC(s).

Operate the vehicle within conditions noted in the
Failure Records and Freeze Frame data.

Monitor the DTC status information for the specific
DTC which has been diagnosed until the diagnostic
test associated with that DTC runs.
EOBD SERVICEABILITY ISSUES
Based on the knowledge gained from Euro On-Board
Diagnostic (OBD) experience in the 1994 and 1995
model years in United Status, this list of non-vehicle
faults that could affect the performance of the Euro On-
Board Diagnostic (EOBD) system has been compiled.
These non-vehicle faults vary from environmental condi-
tions to the quality of fuel used. With the introduction of
EOBD across the entire passenger car, illumination of
the Malfunction Indicator Lamp (MIL) due to a non-ve-
hicle fault could lead to misdiagnosis of the vehicle, in-
creased warranty expense and customer
dissatisfaction. The following list of non-vehicle faults
does not include every possible fault and may not apply
equally to all product lines.
Fuel Quality
Fuel quality is not a new issue for the automotive indus-
try, but its potential for turning on the MIL with EOBD
systems is new.
Fuel additives such as “dry gas” and “octane enhancers”
may affect the performance of the fuel. If this results in
an incomplete combustion or a partial burn, it will set
Diagnostic Trouble Code (DTC) P0300. The Reed Vapor
Pressure of the fuel can also create problems in the fuel
system, especially during the spring and fall months
when severe ambient temperature swings occur. A high
Reed Vapor Pressure could show up as a Fuel Trim
DTC due to excessive canister loading.
Using fuel with the wrong octane rating for your vehicle
may cause driveability problems. Many of the major fuel
companies advertise that using “premium” gasoline will
improve the performance of your vehicle. Most premium

ENGINE CONTROLS 1F–11
DAEWOO M-150 BL2

The fault identified by the diagnostic test is currently
active.

The fault has been active during this ignition cycle.

The operating conditions at the time of the failure.
Remember, a fuel trim Diagnostic Trouble Code (DTC)
may be triggered by a list of vehicle faults. Make use of
all information available (other DTCs stored, rich or lean
condition, etc.) when diagnosing a fuel trim fault.
COMPREHENSIVE COMPONENT
MONITOR DIAGNOSTIC OPERATION
Comprehensive component monitoring diagnostics are
required to monitor emissions-related input and output
powertrain components.
Input Components
Input components are monitored for circuit continuity
and out-of-range values. This includes rationality check-
ing. Rationality checking refers to indicating a fault when
the signal from a sensor does not seem reasonable, i.e.
Throttle Position (TP) sensor that indicates high throttle
position at low engine loads or Manifold Absolute Pres-
sure (MAP) voltage. Input components may include, but
are not limited to, the following sensors:

Vehicle Speed Sensor (VSS).

Crankshaft Position (CKP) sensor.

Throttle Position (TP) sensor.

Engine Coolant Temperature (ECT) sensor.

Camshaft Position (CMP) sensor.

MAP sensor.
In addition to the circuit continuity and rationality check,
the ECT sensor is monitored for its ability to achieve a
steady state temperature to enable closed loop fuel con-
trol.
Output Components
Output components are diagnosed for proper response
to control module commands. Components where func-
tional monitoring is not feasible will be monitored for cir-
cuit continuity and out-of-range values if applicable.
Output components to be monitored include, but are not
limited to the following circuit:

Idle Air Control (IAC) Motor.

Controlled Canister Purge Valve.

A/C relays.

Cooling fan relay.

VSS output.

Malfunction Indicator Lamp (MIL) control.
Refer to “Engine Control Module” and the sections on
Sensors in General Descriptions.
Passive and Active Diagnostic Tests
A passive test is a diagnostic test which simply monitors
a vehicle system or component. Conversely, an activetest, actually takes some sort of action when performing
diagnostic functions, often in response to a failed pas-
sive test. For example, the Electric Exhaust Gas Recir-
culation (EEGR) diagnostic active test will force the
EEGR valve open during closed throttle deceleration
and/or force the EEGR valve closed during a steady
state. Either action should result in a change in manifold
pressure.
Intrusive Diagnostic Tests
This is any Euro On-Board test run by the Diagnostic
Management System which may have an effect on ve-
hicle performance or emission levels.
Warm-Up Cycle
A warm-up cycle means that engine at temperature
must reach a minimum of 70C (160F) and rise at least
22C (40F) over the course of a trip.
Freeze Frame
Freeze Frame is an element of the Diagnostic Manage-
ment System which stores various vehicle information at
the moment an emissions-related fault is stored in
memory and when the MIL is commanded on. These
data can help to identify the cause of a fault.
Failure Records
Failure Records data is an enhancement of the EOBD
Freeze Frame feature. Failure Records store the same
vehicle information as does Freeze Frame, but it will
store that information for any fault which is stored in
Euro On-Board memory, while Freeze Frame stores in-
formation only for emission-related faults that command
the MIL on.
COMMON EOBD TERMS
Diagnostic
When used as a noun, the word diagnostic refers to any
Euro On-Board test run by the vehicle’s Diagnostic Man-
agement System. A diagnostic is simply a test run on a
system or component to determine if the system or com-
ponent is operating according to specification. There are
many diagnostics, shown in the following list:

Misfire.

Oxygen sensors (O2S)

Heated oxygen sensor (HO2S)

Electric Exhaust Gas Recirculation (EEGR)

Catalyst monitoring
Enable Criteria
The term “enable criteria” is engineering language for
the conditions necessary for a given diagnostic test to
run. Each diagnostic has a specific list of conditions
which must be met before the diagnostic will run.
“Enable criteria” is another way of saying “conditions re-
quired.”

1F–12 ENGINE CONTROLS
DAEWOO M-150 BL2
The enable criteria for each diagnostic is listed on the
first page of the Diagnostic Trouble Code (DTC) descrip-
tion under the heading “Conditions for Setting the DTC.”
Enable criteria varies with each diagnostic and typically
includes, but is not limited to the following items:

Engine speed.

Vehicle speed

Engine Coolant Temperature (ECT)

Manifold Absolute Pressure (MAP)

Barometric Pressure (BARO)

Intake Air Temperature (IAT)

Throttle Position (TP)

High canister purge

Fuel trim

A/C on
Trip
Technically, a trip is a key-on run key-off cycle in which
all the enable criteria for a given diagnostic are met, al-
lowing the diagnostic to run. Unfortunately, this concept
is not quite that simple. A trip is official when all the en-
able criteria for a given diagnostic are met. But because
the enable criteria vary from one diagnostic to another,
the definition of trip varies as well. Some diagnostics are
run when the vehicle is at operating temperature, some
when the vehicle first starts up; some require that the
vehicle cruise at a steady highway speed, some run only
when the vehicle is at idle. Some run only immediately
following a cold engine start-up.
A trip then, is defined as a key-on run-key off cycle in
which the vehicle is operated in such a way as to satisfy
the enable criteria for a given diagnostic, and this diag-
nostic will consider this cycle to be one trip. However,
another diagnostic with a different set of enable criteria
(which were not met) during this driving event, would not
consider it a trip. No trip will occur for that particular
diagnostic until the vehicle is driven in such a way as to
meet all the enable criteria.
Diagnostic Information
The diagnostic charts and functional checks are de-
signed to locate a faulty circuit or component through a
process of logical decisions. The charts are prepared
with the requirement that the vehicle functioned correct-
ly at the time of assembly and that there are not multiple
faults present.
There is a continuous self-diagnosis on certain control
functions. This diagnostic capability is complimented by
the diagnostic procedures contained in this manual. The
language of communicating the source of the malfunc-
tion is a system of diagnostic trouble codes. When a
malfunction is detected by the control module, a DTC is
set, and the Malfunction Indicator Lamp (MIL) is illumi-
nated.
Malfunction Indicator Lamp (MIL)
The Malfunction Indicator Lamp (MIL) is required by
Euro On-Board Diagnostics (EOBD) to illuminate under
a strict set of guidelines.
Basically, the MIL is turned on when the Engine Control
Module (ECM) detects a DTC that will impact the vehicle
emissions.
The MIL is under the control of the Diagnostic Execu-
tive. The MIL will be turned on if an emissions-related
diagnostic test indicates a malfunction has occurred. It
will stay on until the system or component passes the
same test for three consecutive trips with no emissions
related faults.
Extinguishing the MIL
When the MIL is on, the Diagnostic Executive will turn
off the MIL after three consecutive trips that a “test
passed” has been reported for the diagnostic test that
originally caused the MIL to illuminate. Although the MIL
has been turned off, the DTC will remain in the ECM
memory (both Freeze Frame and Failure Records) until
forty (40) warm-up cycles after no faults have been com-
pleted.
If the MIL was set by either a fuel trim or misfire-related
DTC, additional requirements must be met. In addition
to the requirements stated in the previous paragraph,
these requirements are as follows:

The diagnostic tests that are passed must occur with
375 rpm of the rpm data stored at the time the last
test failed.

Plus or minus ten percent of the engine load that was
stored at the time the last test failed. Similar engine
temperature conditions (warmed up or warming up)
as those stored at the time the last test failed.
Meeting these requirements ensures that the fault which
turned on the MIL has been corrected.
The MIL is on the instrument panel and has the following
functions:

It informs the driver that a fault affecting the vehicle’s
emission levels has occurred and that the vehicle
should be taken for service as soon as possible.

As a system check, the MIL will come on with the key
ON and the engine not running. When the engine is
started, the MIL will turn OFF.

When the MIL remains ON while the engine is run-
ning, or when a malfunction is suspected due to a
driveability or emissions problem, an EOBD System
Check must be performed. The procedures for these
checks are given in EOBD System Check. These
checks will expose faults which may not be detected
if other diagnostics are performed first.

1F–14 ENGINE CONTROLS
DAEWOO M-150 BL2
termittent fault will also be erased from memory. If the
fault that caused the DTC to be stored into memory has
been corrected, the Diagnostic Executive will begin to
count the ‘‘warm-up” cycles with no further faults de-
tected, the DTC will automatically be cleared from the
Engine Control Module (ECM) memory.
To clear DTCs, use the diagnostic scan tool.
It can’t cleared DTCs without the diagnostic scan tool.
So you must use the diagnostic scan tool.
Notice: To prevent system damage, the ignition key
must be OFF when disconnecting or reconnecting bat-
tery power.

The power source to the control module. Examples:
fuse, pigtail at battery ECM connectors, etc.

The negative battery cable. (Disconnecting the nega-
tive battery cable will result in the loss of other Euro
On-Board memory data, such as preset radio tuning.)
DTC Modes
On Euro On-Board Diagnostic (EOBD) passenger cars
there are five options available in the scan tool DTC
mode to display the enhanced information available. A
description of the new modes, DTC Info and Specific
DTC, follows. After selecting DTC, the following menu
appears:

DTC Info.

Specific DTC.

Freeze Frame.

Fail Records (not all applications).

Clear Info.
The following is a brief description of each of the sub
menus in DTC Info and Specific DTC. The order in
which they appear here is alphabetical and not neces-
sarily the way they will appear on the scan tool.
DTC Information Mode
Use the DTC info mode to search for a specific type of
stored DTC information. There are seven choices. The
service manual may instruct the technician to test for
DTCs in a certain manner. Always follow published ser-
vice procedures.
To get a complete description of any status, press the
‘‘Enter” key before pressing the desired F-key. For ex-
ample, pressing ‘‘Enter” then an F-key will display a defi-
nition of the abbreviated scan tool status.
DTC Status
This selection will display any DTCs that have not run
during the current ignition cycle or have reported a test
failure during this ignition up to a maximum of 33 DTCs.
DTC tests which run and pass will cause that DTC num-
ber to be removed from the scan tool screen.
Fail This Ign. (Fail This Ignition)
This selection will display all DTCs that have failed dur-
ing the present ignition cycle.
History
This selection will display only DTCs that are stored in
the ECM’s history memory. It will not display Type B
DTCs that have not requested the Malfunction Indicator
Lamp (MIL). It will display all type A, B and E DTCs that
have requested the MIL and have failed within the last
40 warm-up cycles. In addition, it will display all type C
and type D DTCs that have failed within the last 40
warm-up cycles.
Last Test Fail
This selection will display only DTCs that have failed the
last time the test ran. The last test may have run during
a previous ignition cycle if a type A or type B DTC is dis-
played. For type C and type D DTCs, the last failure
must have occurred during the current ignition cycle to
appear as Last Test Fail.
MIL Request
This selection will display only DTCs that are requesting
the MIL. Type C and type D DTCs cannot be displayed
using this option. This selection will report type B and E
DTCs only after the MIL has been requested.
Not Run SCC (Not Run Since Code Clear)
This option will display up to 33 DTCs that have not run
since the DTCs were last cleared. Since the displayed
DTCs have not run, their condition (passing or failing) is
unknown.
Test Fail SCC (Test Failed Since Code
Clear)
This selection will display all active and history DTCs
that have reported a test failure since the last time DTCs
were cleared. DTCs that last failed more than 40 warm-
up cycles before this option is selected will not be dis-
played.
Specific DTC Mode
This mode is used to check the status of individual diag-
nostic tests by DTC number. This selection can be ac-
cessed if a DTC has passed, failed or both. Many EOBD
DTC mode descriptions are possible because of the ex-
tensive amount of information that the diagnostic execu-
tive monitors regarding each test. Some of the many
possible descriptions follow with a brief explanation.
The “F2” key is used, in this mode, to display a descrip-
tion of the DTC. The “Ye s” and “No” keys may also be
used to display more DTC status information. This
selection will only allow entry of DTC numbers that are
supported by the vehicle being tested. If an attempt is,

ENGINE CONTROLS 1F–17
DAEWOO M-150 BL2
DIAGNOSTIC INFORMATION AND PROCEDURES
SYSTEM DIAGNOSIS
DIAGNOSTIC AIDS
If an intermittent problem is evident, follow the guide-
lines below.
Preliminary Checks
Before using this section you should have already per-
formed the “Euro On-Board Diagnostic (EOBD) System
Check.”
Perform a thorough visual inspection. This inspection
can often lead to correcting a problem without further
checks and can save valuable time. Inspect for the fol-
lowing conditions:

Engine Control Module (ECM) grounds for being
clean, tight, and in their proper location.

Vacuum hoses for splits, kinks, collapsing and proper
connections as shown on the Vehicle Emission Con-
trol Information label. Inspect thoroughly for any type
of leak or restriction.

Air leaks at the throttle body mounting area and the
intake manifold sealing surfaces.

Ignition wires for cracks, hardness, proper routing,
and carbon tracking.

Wiring for proper connections.

Wiring for pinches or cuts.
Diagnostic Trouble Code Tables
Do not use the Diagnostic Trouble Code (DTC) tables to
try and correct an intermittent fault. The fault must be
present to locate the problem.
Incorrect use of the DTC tables may result in the unnec-
essary replacement of parts.
Faulty Electrical Connections or Wiring
Most intermittent problems are caused by faulty electri-
cal connections or wiring. Perform a careful inspection
of suspect circuits for the following:

Poor mating of the connector halves.

Terminals not fully seated in the connector body.

Improperly formed or damaged terminals. All connec-
tor terminals in a problem circuit should be carefullyinspected, reformed, or replaced to insure contact
tension.

Poor terminal-to-wire connection. This requires re-
moving the terminal from the connector body.
Road Test
If a visual inspection does not find the cause of the prob-
lem, the vehicle can be driven with a voltmeter or a scan
tool connected to a suspected circuit. An abnormal volt-
age or scan tool reading will indicate that the problem is
in that circuit.
If there are no wiring or connector problems found and a
DTC was stored for a circuit having a sensor, except for
DTC P0171 and DTC P0172, replace the sensor.
Intermittent Malfunction Indicator Lamp
(MIL)
An intermittent Malfunction Indicator Lamp(MIL) with no
DTC present may be caused by the following:

Improper installation of electrical options such as
lights, two way radios, sound, or security systems.

MIL driver wire intermittently shorted to ground.
Fuel System
Some intermittent driveability problems can be attrib-
uted to poor fuel quality. If a vehicle is occasionally run-
ning rough, stalling, or otherwise performing badly, ask
the customer about the following fuel buying habits:

Do they always buy from the same source? If so, fuel
quality problems can usually be discounted.

Do they buy their fuel from whichever fuel station that
is advertising the lowest price? If so, check the fuel
tank for signs of debris, water, or other contamina-
tion.
IDLE LEARN PROCEDURE
Whenever the battery cables, the Engine Control Mod-
ule (ECM), or the fuse is disconnected or replaced, the
following idle learn procedure must be performed:
1. Turn the ignition ON for 10 seconds.
2. Turn the ignition OFF for 10 seconds.

1F–18 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F010
EURO ON-BOARD DIAGNOSTIC (EOBD) SYSTEM CHECK
Circuit Description
The Euro On-Board Diagnostic (EOBD) System Check
is the starting point for any driveability complaint diagno-
sis. Before using this procedure, perform a careful visu-
al/physical check of the Engine Control Module (ECM)
and the engine grounds for cleanliness and tightness.
The EOBD system check is an organized approach to
identifying a problem created by an electronic engine
control system malfunction.Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside
the insulation. Check for poor connections or a dam-
aged harness. Inspect the ECM harness and connec-
tions for improper mating, broken locks, improperly
formed or damaged terminals, poor terminal-to-wire
connections, and damaged harness.

ENGINE CONTROLS 1F–19
DAEWOO M-150 BL2
Euro On-Board Diagnostic (EOBD) System Check
StepActionValue(s)YesNo
1
1. Turn the ignition ON with the engine OFF.
2. Observe the Malfunction Indicator Lamp (MIL).
Is the MIL on?
–
Go to Step 2
Go to “No
Malfunction
Indicator
Lamp”
2
1. Turn the ignition OFF.
2. Install the scan tool.
3. Turn the ignition ON.
4. Attempt to display the Engine Control Module
(ECM) engine data with the scan tool.
Does the scan tool display the ECM engine data?
–
Go to Step 3Go to Step 8
3
1. Using the scan tool output test function, select the
MIL lamp control and command the MIL off.
2. Observe the MIL.
Does the MIL turn off?
–
Go to Step 4
Go to
“Malfunction
Indicator Lamp
on Steady”
4
Attempt to start the engine.
Does the engine start and continue to run?
–
Go to Step 5
Go to “Engine
Cranks But
Will Not Run”
5Select DISPLAY DTC with the scan tool.
Are any Diagnostic Trouble Codes stored?–Go to Step 6Go to Step 7
6
Check the display for DTCs P0107, P0108, P0113,
P0118, P0122, P0123, P0172, P1392.
Are two or more of the following DTCs stored?
–
Go to “Multiple
ECM
Information
Sensor DTCs
Set”
Go to
applicable DTC
table
7
Compare the ECM data values displayed on the
scan tool to the typical engine scan data values.
Are the displayed values normal or close to the
typical values?
–Go to “ECM
Output
Diagnosis”Go to indicated
component
system check
8
1. Turn the ignition OFF and disconnect the ECM.
2. Turn the ignition ON with the engine OFF.
3. Check the serial data circuit for an open, short to
ground, or short to voltage. Also check the Data
Link Connector (DLC) ignition feed circuit for an
open or short to ground, and check the DLC
ground circuits for an open.
Is a problem found?
–
Go to Step 9Go to Step 10
9
Repair the open, short to ground, or short to voltage
in the serial data circuit or the DLC ignition feed
circuit.
Is the repair complete?
–
System OK
–
10
1. Attempt to reprogram the ECM.
2. Attempt to display the ECM data with the scan
tool.
Does the scan tool display ECM engine data?
–
Go to Step 2Go to Step 11
11Replace the ECM.
Is the repair complete?–System OK–

1F–20 ENGINE CONTROLS
DAEWOO M-150 BL2
ECM OUTPUT DIAGNOSIS
Circuit Description
The Engine Control Module (ECM) controls most com-
ponents with electronic switches which complete a
ground circuit when turned on. These switches are ar-
ranged in groups of 4 and 7, and they are called either a
Surface Mounted Quad Driver Module, which can inde-
pendently control up to 4 output terminals or an Output
Driver Module (ODM), which can independently control
up to 7 outputs. Not all of the outputs are always used.
Drivers are fault protected. If a relay or solenoid is
shorted, having very low or zero resistance, or if the con-
trol side of the circuit is shorted to voltage, it would allow
too much current flow into the ECM. The driver senses
this and the output is either turned OFF or its internal re-
sistance increases to limit current flow and protect the
ECM and driver. The result is high output terminal volt-
age when it should be low. If the circuit from B+ to the
component or the component is open, or the control side
of the circuit is shorted to ground, terminal voltage willbe low. Either of these conditions is considered to be a
driver fault.
Drivers also have a fault line to indicate the presence of
a current fault to the ECM’s central processor. A scan
tool displays the status of the driver fault lines as 0=OK
and 1=Fault.
Diagnostic Aids
The scan tool has the ability to command certain compo-
nents and functions ON and OFF. If a component or
function does not have this capability, operate the ve-
hicle during its normal function criteria to check for an
open or shorted circuit.
An open or short to ground will appear in the open posi-
tions on the scan tool only when it is not commanded by
the ECM or the scan tool, while a short to voltage will
appear in the short positions on the scan tool only while
the component is being commanded by the ECM or
scan tool.
ECM Output Diagnosis
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the check complete.
–
Go to Step 2
Go to “Euro
On-Board
Diagnostic
System Check”
2
Install the scan tool.
Is there a number 1 (=fault) below any of the
numbered positions in the OUTPUT DRIVERS?
–
Go to Step 3Go to Step 4
3
Check for an open or shorted circuit in any
corresponding position (circuit) that contained a
number 1 and repair as necessary.
Is a repair necessary?
–
Go to Step 9Go to Step 7
4
Command the output being checked with a scan tool
while watching the corresponding position for each
circuit.
Do any of the position changed to a 1?
–
Go to Step 6Go to Step 5
5
Command the output being checked with a scan tool
while watching the corresponding position for each
circuit.
Does the component or function operate when
commanded?
–
Go to Step 9
Go to the
appropriate
component
table for repair
6
Repair the short to voltage in the corresponding
circuit for position (circuit) that displayed at a 1.
Is the repair complete?
–
Go to Step 9
–
7
Disconnect the electrical connector to the
component connected to the fault circuit.
Is a 1 still displayed in the corresponding OUTPUT
DRIVER position?
–
Go to Step 8
Go to the
appropriate
component
table for repair
8Replace the Engine control Module (ECM).
Is the repair complete?–Go to Step 9–
9
Operate the vehicle within the conditions under
which the original symptom was noted.
Does the system now operate properly?
–
System OKGo to Step 2

ENGINE CONTROLS 1F–21
DAEWOO M-150 BL2
MULTIPLE ECM INFORMATION SENSOR DTCS SET
Circuit Description
The Engine Control Module (ECM) monitors various
sensors to determine engine operating conditions. The
ECM controls fuel delivery, spark advance, transaxle op-
eration, and emission control device operation based on
the sensor inputs.
The ECM provides a sensor ground to all of the sensors.
The ECM applies 5 volts through a pull-up resistor and
monitors the voltage present between the sensor and
the resistor to determine the status of the Engine Cool-
ant Temperature (ECT) sensor, the Intake Air Tempera-
ture (IAT) sensor. The ECM provides the Electric
Exhaust Gas Recirculation (EEGR) Pintle Position Sen-
sor, the Throttle Position (TP) sensor, the Manifold Ab-
solute Pressure (MAP) sensor, and the Fuel Tank
Pressure Sensor with a 5 volt reference and a sensor
ground signal. The ECM monitors the separate feed-
back signals from these sensors to determine their oper-
ating status.
Diagnostic Aids
Be sure to inspect the ECM and the engine grounds for
being secure and clean.
A short to voltage in one of the sensor circuits can cause
one or more of the following DTCs to be set: P0108,
P0113, P0118, P0123, P1106.If a sensor input circuit has been shorted to voltage, en-
sure that the sensor is not damaged. A damaged sensor
will continue to indicate a high or low voltage after the
affected circuit has been repaired. If the sensor has
been damaged, replace it.
An open in the sensor ground circuit between the ECM
and the splice will cause one or more of the following
DTCs to be set: P0108, P0113, P0118, P0123, P1106.
A short to ground in the 5 volt reference circuit or an
open in the 5 volt reference circuit between the ECM
and the splice will cause one or more of the following
DTCs to be set: P0107, P0112, P0117, P0122, P1107.
Check for the following conditions:

Inspect for a poor connection at the ECM. Inspect
harness connectors for backed-out terminals, im-
proper mating, broken locks, improperly formed or
damaged terminals, and poor terminal-to-wire con-
nection.

Inspect the wiring harness for damage. If the harness
appears to be OK, observe an affected sensor’s dis-
played value on the scan tool with the ignition ON and
the engine OFF while moving connectors and wiring
harnesses related to the affected sensors. A change
in the affected sensor’s displayed value will indicate
the location of the fault.

1F–22 ENGINE CONTROLS
DAEWOO M-150 BL2
Multiple ECM Information Sensor DTCs Set
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the check complete.
–
Go to Step 2
Go to “Euro
On-Board
Diagnostic
System Check”
2
1. Turn the ignition OFF and disconnect the Engine
Control Module (ECM).
2. Turn the ignition ON and check the 5 volt
reference circuit for the following conditions:

Poor connection at the ECM.

Open between the ECM connector affected
sensors shorted to ground or voltage.
3. If a problem is found, locate and repair the open
or short circuit as necessary.
Is a problem found?
–
Go to Step 19Go to Step 3
3
1. Check the sensor ground circuit for the following
conditions:

Poor connection at the ECM or affected
sensors.

Open between the ECM connector and the
affected sensors.
2. If a problem is found, repair it as necessary.
Is a problem found?
–
Go to Step 19Go to Step 4
4
Measure the voltage of the Electric Exhaust Gas
Recirculation (EEGR) Pintle Position Sensor signal
circuit between ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 5Go to Step 9
5
Measure the voltage of the Manifold Absolute
Pressure (MAP) sensor signal circuit between the
ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 6Go to Step 11
6
Measure the voltage of the Throttle Position (TP)
sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 7Go to Step 12
7
Measure the voltage of the Intake Air Temperature
(IAT) sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 8Go to Step 13
8
Measure the voltage of the Engine Coolant
Temperature (ECT) sensor signal circuit between the
ECM harness connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 16Go to Step 14
9
1. Disconnect the EEGR valve.
2. Measure the voltage of the EEGR Pintle Position
sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 10Go to Step 15
10Replace the EEGR valve.
Is the repair complete?–Go to Step 19–
11
Locate and repair the short to voltage in the MAP
sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–