fuel DAEWOO MATIZ 2003 Service Owner's Manual

ENGINE CONTROLS 1F–13
DAEWOO M-150 BL2
Data Link Connector (DLC)
The provision for communicating with the control mod-
ule is the Data Link Connector (DLC). The DLC is used
to connect to a scan tool. Some common uses of the
scan tool are listed below:

Identifying stored DTCs.

Clearing DTCs.

Performing output control tests.

Reading serial data.
DTC TYPES
Each Diagnostic Trouble Code (DTC) is directly related
to a diagnostic test. The Diagnostic Management Sys-
tem sets DTCs based on the failure of the tests during a
trip or trips. Certain tests must fail two consecutive trips
before the DTC is set. The following are the three types
of DTCs and the characteristics of those codes:
Type A

Emissions related.

Requests illumination of the Malfunction Indicator.
Lamp (MIL) of the first trip with a fail.

Stores a History DTC on the first trip with a fail.

Stores a Freeze Frame (if empty).

Stores a Fail Record.

Updates the Fail Record each time the diagnostic test
fails.
Type B

Emissions related.

“Armed” after one trip with a fail.

“Disarmed” after one trip with a pass.

Requests illumination of the MIL on the second con-
secutive trip with a fail.

Stores a History DTC on the second consecutive trip
with a fail (The DTC will be armed after the first fail).

Stores a Freeze Frame on the second consecutive
trip with a fail (if empty).
Type Cnl

Non-Emissions related.

Does not request illumination of any lamp.

Stores a History DTC on the first trip with a fail .

Does not store a Freeze Frame.

Stores Fail Record when test fails.

Updates the Fail Record each time the diagnostic test
fails.
Type E

Emissions related.

“Armed” after two consecutive trip with a fail.

“Disarmed” after one trip with a pass.
Requests illumination of the MIL on the third consec-
utive trip with a fail.

Stores a History DTC on the third consecutive trip
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).
Important: For 0.8 SOHC engine eight fail records can
be stored. Each Fail Record is for a different DTC. It is
possible that there will not be Fail Records for every
DTC if multiple DTCs are set.
Special Cases of Type B Diagnostic Tests
Unique to the misfire diagnostic, the Diagnostic Execu-
tive has the capability of alerting the vehicle operator to
potentially damaging levels of misfire. If a misfire condi-
tion exists that could potentially damage the catalytic
converter as a result of high misfire levels, the Diagnos-
tic Executive will command the MIL to “flash” as a rate of
once per seconds during those the time that the catalyst
damaging misfire condition is present.
Fuel trim and misfire are special cases of Type B diag-
nostics. Each time a fuel trim or misfire malfunction is
detected, engine load, engine speed, and Engine Cool-
ant Temperature (ECT) are recorded.
When the ignition is turned OFF, the last reported set of
conditions remain stored. During subsequent ignition
cycles, the stored conditions are used as a reference for
similar conditions. If a malfunction occurs during two
consecutive trips, the Diagnostic Executive treats the
failure as a normal Type B diagnostic, and does not use
the stored conditions. However, if a malfunction occurs
on two non-consecutive trips, the stored conditions are
compared with the current conditions. The MIL will then
illuminate under the following conditions:

When the engine load conditions are within 10% of
the previous test that failed.

Engine speed is within 375 rpm, of the previous test
that failed.

ECT is in the same range as the previous test that
failed.
READING DIAGNOSTIC TROUBLE
CODES
The procedure for reading Diagnostic Trouble Code(s)
(DTC) is to use a diagnostic scan tool. When reading
DTC(s), follow instructions supplied by tool manufactur-
er.
Clearing Diagnostic Trouble Codes
Important: Do not clear DTCs unless directed to do so
by the service information provided for each diagnostic
procedure. When DTCs are cleared, the Freeze Frame
and Failure Record data which may help diagnose an in-

ENGINE CONTROLS 1F–15
DAEWOO M-150 BL2
made to enter DTC numbers for tests which the diag-
nostic executive does not recognize, the requested in-
formation will not be displayed correctly and the scan
tool may display an error message. The same applies to
using the DTC trigger option in the Snapshot mode. If an
invalid DTC is entered, the scan tool will not trigger.
Failed Last Test
This message display indicates that the last diagnostic
test failed for the selected DTC. For type A, B and E
DTCs, this message will be displayed during subse-
quent ignition cycles until the test passes or DTCs are
cleared. For type C and type D DTCs, this message will
clear when the ignition is cycled.
Failed Since Clear
This message display indicates that the DTC has failed
at least once within the last 40 warm-up cycles since the
last time DTCs were cleared.
Failed This Ig. (Failed This Ignition)
This message display indicates that the diagnostic test
has failed at least once during the current ignition cycle.
This message will clear when DTCs are cleared or the
ignition is cycled.
History DTC
This message display indicates that the DTC has been
stored in memory as a valid fault. A DTC displayed as a
History fault may not mean that the fault is no longer
present. The history description means that all the con-
ditions necessary for reporting a fault have been met
(maybe even currently), and the information was stored
in the control module memory.
MIL Requested
This message display indicates that the DTC is currently
causing the MIL to be turned ON. Remember that only
type A B and E DTCs can request the MIL. The MIL re-
quest cannot be used to determine if the DTC fault con-
ditions are currently being experienced. This is because
the diagnostic executive will require up to three trips dur-
ing which the diagnostic test passes to turn OFF the
MIL.
Not Run Since CI (Not Run Since Cleared)
This message display indicates that the selected diag-
nostic test has not run since the last time DTCs were
cleared. Therefore, the diagnostic test status (passing
or failing) is unknown. After DTCs are cleared, this mes-
sage will continue to be displayed until the diagnostic
test runs.
Not Run This Ig. (Not Run This Ignition)
This message display indicates that the selected diag-
nostic test has not run during this ignition cycle.
Test Ran and Passed
This message display indicates that the selected diag-
nostic test has done the following:
Passed the last test.

Run and passed during this ignition cycle.

Run and passed since DTCs were last cleared.
If the indicated status of the vehicle is “Test Ran and
Passed” after a repair verification, the vehicle is ready to
be released to the customer.
If the indicated status of the vehicle is “Failed This Igni-
tion” after a repair verification, then the repair is incom-
plete and further diagnosis is required.
Prior to repairing a vehicle, status information can be
used to evaluate the state of the diagnostic test, and to
help identify an intermittent problem. The technician can
conclude that although the MIL is illuminated, the fault
condition that caused the code to set is not present. An
intermittent condition must be the cause.
PRIMARY SYSTEM-BASED
DIAGNOSTICS
There are primary system-based diagnostics which
evaluate the system operation and its effect on vehicle
emissions. The primary system-based diagnostics are
listed below with a brief description of the diagnostic
function:
Oxygen Sensor Diagnosis
The fuel control oxygen sensor (O2S) is diagnosed for
the following conditions:

Few switch count (rich to lean or lean to rich).

Slow response (average transient time lean to rich or
rich to lean).

Response time ratio (ratio of average transient time
rich(lean) to lean(rich)).

Inactive signal (output steady at bias voltage approxi-
mately 450 mV).

Signal fixed high.

Signal fixed low.
The catalyst monitor heated oxygen sensor (HO2S) is
diagnosed for the following conditions:

Heater performance (current during IGN on).

Signal fixed low during steady state conditions or
power enrichment (hard acceleration when a rich mix-
ture should be indicated).

Signal fixed high during steady state conditions or de-
celeration mode (deceleration when a lean mixture
should be indicated).

Inactive sensor (output steady at approx. 438 mV).
If the O2S pigtail wiring, connector or terminal are dam-
aged, the entire O2S assembly must be replaced. Do
not attempt to repair the wiring, connector or terminals.
In order for the sensor to function properly, it must have
clean reference air provided to it. This clean air refer-
ence is obtained by way of the O2S wire(s). Any attempt
to repair the wires, connector or terminals could result in

1F–16 ENGINE CONTROLS
DAEWOO M-150 BL2
the obstruction of the reference air and degrade the O2S
performance.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft
rotational velocity (reference period) variations. The En-
gine Control Module (ECM) determines crankshaft rota-
tional velocity using the Crankshaft Position (CKP)
sensor and the Camshaft Position (CMP) sensor. When
a cylinder misfires, the crankshaft slows down momen-
tarily. By monitoring the CKP and CMP sensor signals,
the ECM can calculate when a misfire occurs.
For a non-catalyst damaging misfire, the diagnostic will
be required to monitor a misfire present for between
1000–3200 engine revolutions.
For catalyst-damaging misfire, the diagnostic will re-
spond to misfire within 200 engine revolutions.
Rough roads may cause false misfire detection. A rough
road will cause torque to be applied to the drive wheels
and drive train. This torque can intermittently decrease
the crankshaft rotational velocity. This may be falsely
detected as a misfire.
A rough road sensor, or “G sensor,” works together with
the misfire detection system. The rough road sensor
produces a voltage that varies along with the intensity of
road vibrations. When the ECM detects a rough road,
the misfire detection system is temporarily disabled.
Misfire Counters
Whenever a cylinder misfires, the misfire diagnostic
counts the misfire and notes the crankshaft position at
the time the misfire occurred. These “misfire counters”
are basically a file on each engine cylinder. A current
and a history misfire counter are maintained for each
cylinder. The misfire current counters (Misfire Current
#1–4) indicate the number of firing events out of the last
200 cylinder firing events which were misfires. The mis-
fire current counter will display real time data without a
misfire DTC stored. The misfire history counters (Misfire
Histtory #1–4) indicate the total number of cylinder firing
events which were misfires. The misfire history counters
will display 0 until the misfire diagnostic has failed and a
DTC P0300 is set. Once the misfire DTC P0300 is set,
the misfire history counters will be updated every 200
cylinder firing events. A misfire counter is maintained for
each cylinder.
If the misfire diagnostic reports a failure, the diagnostic
executive reviews all of the misfire counters before re-
porting a DTC. This way, the diagnostic executive re-
ports the most current information.
When crankshaft rotation is erratic, a misfire condition
will be detected. Because of this erratic condition, the
data that is collected by the diagnostic can sometimes
incorrectly identify which cylinder is misfiring.
Use diagnostic equipment to monitor misfire counter
data on EOBD compliant vehicles. Knowing which spe-
cific cylinder(s) misfired can lead to the root cause, evenwhen dealing with a multiple cylinder misfire. Using the
information in the misfire counters, identify which cylin-
ders are misfiring. If the counters indicate cylinders
numbers 1 and 4 misfired, look for a circuit or compo-
nent common to both cylinders number 1 and 4.
The misfire diagnostic may indicate a fault due to a tem-
porary fault not necessarily caused by a vehicle emis-
sion system malfunction. Examples include the following
items:

Contaminated fuel.

Low fuel.

Fuel-fouled spark plugs.

Basic engine fault.
Fuel Trim System Monitor Diagnostic
Operation
This system monitors the averages of short-term and
long-term fuel trim values. If these fuel trim values stay
at their limits for a calibrated period of time, a malfunc-
tion is indicated. The fuel trim diagnostic compares the
averages of short-term fuel trim values and long-term
fuel trim values to rich and lean thresholds. If either val-
ue is within the thresholds, a pass is recorded. If both
values are outside their thresholds, a rich or lean DTC
will be recorded.
The fuel trim system diagnostic also conducts an intru-
sive test. This test determines if a rich condition is being
caused by excessive fuel vapor from the controlled char-
coal canister. In order to meet EOBD requirements, the
control module uses weighted fuel trim cells to deter-
mine the need to set a fuel trim DTC. A fuel trim DTC
can only be set if fuel trim counts in the weighted fuel
trim cells exceed specifications. This means that the ve-
hicle could have a fuel trim problem which is causing a
problem under certain conditions (i.e., engine idle high
due to a small vacuum leak or rough idle due to a large
vacuum leak) while it operates fine at other times. No
fuel trim DTC would set (although an engine idle speed
DTC or HO2S DTC may set). Use a scan tool to observe
fuel trim counts while the problem is occurring.
A fuel trim DTC may be triggered by a number of vehicle
faults. Make use of all information available (other DTCs
stored, rich or lean condition, etc.) when diagnosing a
fuel trim fault.
Fuel Trim Cell Diagnostic Weights
No fuel trim DTC will set regardless of the fuel trim
counts in cell 0 unless the fuel trim counts in the
weighted cells are also outside specifications. This
means that the vehicle could have a fuel trim problem
which is causing a problem under certain conditions (i.e.
engine idle high due to a small vacuum leak or rough
due to a large vacuum leak) while it operates fine at oth-
er times. No fuel trim DTC would set (although an en-
gine idle speed DTC or HO2S DTC may set). Use a
scan tool to observe fuel trim counts while the problem is
occurring.

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.

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.

ENGINE CONTROLS 1F–23
DAEWOO M-150 BL2
Multiple ECM Information Sensor DTCs Set (Cont’d)
StepActionValue(s)YesNo
12
Locate and repair the short to voltage in the TP
sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–
13
Locate and repair the short to voltage in the IAT
sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–
14
Locate and repair the short to voltage in the ECT
sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–
15
Locate and repair the short to voltage in the EEGR
Pintle Position sensor circuit.
Is the repair complete?
–
Go to Step 19
–
16
Measure the voltage of the Fuel Tank Pressure
sensor signal circuit between the ECM harness
connector and ground.
Does the voltage measure near the specified value?
0 VGo to Step 18Go to Step 17
17
Locate and repair the short to voltage in the Fuel
Tank Pressure sensor signal circuit.
Is the repair complete?
–
Go to Step 19
–
18Replace the ECM.
Is the repair complete?–Go to Step 19–
19
1. Using the scan tool, clear the Diagnostic Trouble
Codes (DTCs).
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting the DTCs as specified in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?
–
Go to Step 20Go to Step 2
20
Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?
–
Go to
Applicable DTC
table
System OK

ENGINE CONTROLS 1F–25
DAEWOO M-150 BL2
ENGINE CRANKS BUT WILL NOT RUN
Caution: Use only electrically insulated pliers when
handling ignition wires with the engine running to
prevent an electrical shock.
Caution: Do not pinch or restrict nylon fuel lines.
Damage to the lines could cause a fuel leak, result-
ing in possible fire or personal injury.Important: If a no start condition exists, ensure the fuel
cutoff switch has not been tripped prior to further diagno-
sis.
Engine Cranks But Will Not Run
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”
2Crank the engine.
Does the engine start and continue to run?–System OkGo to Step 3
3
Perform a cylinder compression test.
Is the cylinder compression for all of the cylinders at
or above the value specified?
1250 kPa
(181 psi)
Go to Step 7Go to Step 4
4Inspect the timing belt alignment.
Is the timing belt in alignment?–Go to Step 6Go to Step 5
5Align or replace the timing belt as needed.
Is the repair complete?–Go to Step 2–
6Repair internal engine damage as needed.
Is the repair complete?–Go to Step 2–
7Inspect the fuel pump fuse.
Is the problem found?–Go to Step 8Go to Step 9
8Replace the fuse.
Is the repair complete?–Go to Step 2–
9
Check for the presence of spark from all of the
ignition wires while cranking the engine.
Is spark present from all of the ignition wires?
–
Go to Step 23Go to Step 10
10
1. Measure the resistance of the ignition wires.
2. Replace any of the ignition wire(s) with a
resistance above the value specified.
3. Check for the presence of spark from all of the
ignition wire.
Is spark present from all of the ignition wires?
5 kΩGo to Step 2Go to Step 11
11
1. Turn the ignition OFF.
2. Disconnect the crankshaft position (CKP) sensor
connector.
3. Turn the ignition ON.
4. Measure the voltage between following terminals:

Terminal 1 and 3 of the CKP sensor connector.

Terminal 2 and 3 of the CKP sensor connector.

Terminal 1 of the CKP sensor connector and
ground.

Terminal 2 of the CKP sensor connector and
ground.
Are the voltage measure within the value specified?
≈ 0.4 VGo to Step 13Go to Step 12

ENGINE CONTROLS 1F–27
DAEWOO M-150 BL2
Engine Cranks But Will Not Run (Cont’d)
StepActionValue(s)YesNo
21
1. Check for any damages or poor connection in
ignition wires and repair as needed.
2. Connect the Ei system ignition coil connector and
ECM connector.
3. Check for the presence of spark from all of the
ignition wires.
Is the spark present from all of the ignition wires?
–
Go to Step 2Go to Step 22
22Replace ECM
Is the repair complete?–Go to Step 2–
23
1. Turn the ignition OFF.
2. Connect a fuel pressure gauge.
3. Crank the engine.
Is any fuel pressure present?
–
Go to Step 26Go to Step 24
24
1. Turn the ignition OFF.
2. Disconnect the electrical connector at the fuel
pump.
3. Connect a test light between the fuel pump
terminals 2 and 3.
4. Turn the ignition ON.
5. With the ignition ON, the test light should light for
the time specified.
Is the test light on?
2 sec.Go to Step 25Go to Step 32
25Replace the fuel pump.
Is the repair complete?–Go to Step 2–
26
Is the fuel pressure within the value specified?
380 kPa
(55 psi)
Go to Step 27Go to Step 29
27Check the fuel for contamination.
Is the fuel contaminated?–Go to Step 28Go to Step 41
28
1. Remove the contaminated fuel from the fuel tank.
2. Clean the fuel tank as needed.
Is the repair complete?
–
Go to Step 2
–
29
1. Check the fuel filter for restriction.
2. Inspect the fuel lines for kinks and restrictions.
3. Repair or replace as needed.
4. Measure the fuel pressure.
Is the fuel pressure within the value specified?
380 kPa
(55 psi)
Go to Step 2Go to Step 30
30
1. Disconnect vacuum line from the fuel pressure
regulator.
2. Inspect the vacuum line for the presence of fuel.
3. Inspect the fuel pressure regulator vacuum port
for the presence of fuel.
Is any fuel present?
–
Go to Step 31Go to Step 32
31Replace the fuel pressure regulator.
Is the repair complete?–Go to Step 2–
32
1. Remove the fuel pump assembly from the fuel
tank.
2. Inspect the fuel pump sender and the fuel
coupling hoses for a restriction.
3. Inspect the in-tank fuel filter for restriction.
Is the problem found?
–
Go to Step 33Go to Step 25

1F–28 ENGINE CONTROLS
DAEWOO M-150 BL2
Engine Cranks But Will Not Run (Cont’d)
StepActionValue(s)YesNo
33
Replace the fuel pump sender, the in-tank fuel filter,
and/or the fuel coupling hoses as needed.
Is the repair complete?
–
Go to Step 2
–
34
1. Turn the ignition OFF.
2. Disconnect the electric connector at the fuel
pump.
3. Connect a test light between fuel pump connector
terminal 3 and ground.
4. Turn the ignition ON.
5. With the ignition ON, the test light should
illuminate for the time specified.
Is the test light on?
2 secGo to Step 35Go to Step 36
35
Repair the open circuit between the fuel pump
connector terminal 2 and ground.
Is the repair complete?
–
Go to Step 2
–
36
1. Turn the ignition OFF.
2. Disconnect the fuel pump relay.
3. Turn the ignition ON.
4. Measure the voltage at terminal 30 and 85 of fuel
pump relay.
Is the voltage within the value specified?
11 – 14 VGo to Step 38Go to Step 37
37Repair open or short circuit for power supply.
Is the repair complete?–Go to Step 2–
38
1. Turn the ignition OFF.
2. Disconnect ECM connector.
3. Using an ohmmeter, measure the resistance
between following terminals.

Terminal 10 of ECM and terminal 85 of fuel
pump relay.

Terminal 87 of fuel pump relay and terminal 3
of fuel pump.
Does the resistance within the value specified?
0 ΩGo to Step 40Go to Step 39
39
1. Check for open circuit and fuel cut–off switch.
2. Reset fuel cut-off switch or repair open circuit as
needed.
Is the repair complete?
–
Go to Step 2
–
40Replace the fuel pump relay.
Is the repair complete?–Go to Step 2–
41
1. Turn the ignition OFF.
2. Disconnect the fuel inject harness connectors
from all of the fuel injectors.
3. Turn the ignition ON.
4. Connect test light between fuel injector harness
connector 1 and ground.
5. Repeat step 4 for each of the remaining fuel
injectors.
Does the test light on at all of the fuel injectors?
–
Go to Step 42Go to Step 45

ENGINE CONTROLS 1F–29
DAEWOO M-150 BL2
Engine Cranks But Will Not Run (Cont’d)
StepActionValue(s)YesNo
42
1. Turn the ignition OFF.
2. Connect test light between fuel injector harness
connector 2 and battery positive.
3. Crank the engine.
4. Repeat step 2 and 3 for each of the remaining
fuel injectors.
Does the test light flash for all of the fuel injectors?
–
Go to Step 43Go to Step 46
43
Measure the resistance of each fuel injectors.
Is the resistance within the value specified.
Note: the resistance will increase slightly at higher
temperature.
13.75–15.25
ΩSystem OKGo to Step 44
44
Replace any of the fuel injectors with a resistance
out of specification.
Is the repair complete?
–
Go to Step 2
–
45
1. Inspect the fuse EF19 in engine fuse block.
2. Check for an open between the circuit from
terminal 2 of the three fuel injectors and terminal
87 of main relay.
Is the problem found?
–
Go to Step 48
Go to “Main
Relay Circuit
Check”
46
Measure the resistance between following terminals.

Terminal 1 of injector 1 connector and terminal 30
of ECM connector.

Terminal 1 of injector 2 connector and terminal 58
of ECM connector.

Terminal 1 of injector 3 connector and terminal 89
of ECM connector.
Does the resistance within the specified value?
0 ΩGo to Step 49Go to Step 47
47Repair the open fuel injector harness wire(s).
Is the repair complete?–Go to Step 2–
48Replace the fuse or repair the wiring as needed.
Is the repair complete?–Go to Step 2–
49Replace the ECM.
Is the repair complete?–Go to Step 2–