2004 DAEWOO LACETTI ignition

1F – 448IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
3Listen to the engine while rising and lowing the en-
gine speed.
Is a knock or audible noise present?–Go to Step 4Go to Step 5
4Repair mechanical engine problem or a loose brack-
et or components as needed.
Is the repair complete?–Go to Step 6–
51. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 6–
61. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 7Go to Step 2
7Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 449
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0327
KNOCK SENSOR CIRCUIT FAULT
System Description
The Knock Sensor (KS) system is used to detect engine
detonation, allowing the Engine Control Module (ECM) to
retard the ignition control spark timing based on the KS
signal being received. The KS produces an AC signal so
that under a no–knock condition the signal on the KS cir-
cuit measures about 0.007 volts AC. The KS signal’s am-
plitude and frequency depend upon the amount of knock
being experienced. The ECM monitors the KS signal and
can diagnose the KS and circuitry.
Conditions for Setting the DTC
S Minimum difference between cylinders is greater
than 0.4%.
S Vacuum is less than the predetermined value (10 to
50 kPa, based on rpm).
S The rpm is greater than 1600.
S DTC(s) P0106, P0107, P0108 are not set.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.Diagnostic Aids
Check and correct any abnormal engine noise before us-
ing the diagnostic table.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions:
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
S Physical damage to the wiring harness
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Table.
1. The On–Board Diagnostic (EOBD) System Check
prompts the technician to complete some basic
checks and store the freeze frame and failure re-
cords data on the scan tool if applicable. This
creates an electronic copy of the data taken when
the malfunction occurred. The information is then
stored on the scan tool for later reference.
2. If the conditions for the test as described above are
met, a DTC P0327 will set and MIL will illuminate.
3. If the engine has an internal knock or audible noise
that causes a knocking type noise on the engine
block, the KS may be responding to the noise.
5. Checking the internal resistance of the KS or the
wiring to the KS is OK.
6. Any circuitry, that is suspected as causing the com-
plaint, should be thoroughly checked for backed–
out terminals, improper mating, broken locks, im-

1F – 450IENGINE CONTROLS
DAEWOO V–121 BL4
properly formed or damaged terminals, poor
terminal–to–wiring connections or physical damage
to the wiring harness.
7. The replacement ECM must be reprogrammed.Refer to the latest Techline procedure for ECM re-
programming.
DTC P0327 – Knock Sensor Circuit Fault
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Was the check performed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Install a scan tool to the Data Link Connector
(DLC).
2. Clear the Diagnostic Trouble Codes (DTCs).
3. Start the engine.
4. Operate the vehicle within the Conditions for
Setting the DTC as noted.
Is the DTC set again.–Go to Step 3Go to Step 6
3Listen to the engine while rising and lowing the en-
gine speed.
Is a knock or audible noise present?–Go to Step 4Go to Step 5
4Repair mechanical engine problem or a loose brack-
et or components as needed.
Is the repair complete?–Go to Step 11–
51. Turn the ignition OFF.
2. Disconnect the Engine Control Module (ECM)
connector.
3. With a ohmmeter connected ground, measure
the resistance of the Knock Sensor (KS)
through the KS signal circuit, terminal M18.
Is the resistance between the specified value?90–110 kΩGo to Step 6Go to Step 8
6Check for a poor connection at the ECM connector
KS signal circuit and repair as needed.
Is the repair complete?–Go to Step 11Go to Step 7
71. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 11 –
8Check the KS connector for a poor connection and
repair as needed.
Is the repair complete?–Go to Step 11Go to Step 9
9Check the KS signal circuit for an open or a short to
ground or voltage and repair as needed.
Is the repair complete?–Go to Step 11–
101. Turn the ignition OFF.
2. Replace the KS.
Is the repair complete?–Go to Step 11–

1F – 452IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0336
58X CRANK POSITION SENSOR EXTRA/MISSING
PULSES
Circuit Description
The 58X reference signal is produced by the Crankshaft
Position (CKP) sensor. During one crankshaft revolution,
58 crankshaft pulses will be produced. The Engine Control
Module (ECM) uses the 58X reference signal to calculate
engine rpm and CKP. The ECM constantly monitors the
number of pulses on the 58X reference circuit and
compares them to the number of Camshaft Position
(CMP) signal pulses being received. If the ECM receives
and incorrect number of pulses on the 58X reference cir-
cuit, Diagnostic Trouble Code (DTC) P0336 will set.
Conditions for Setting the DTC
S Engine is running.
S Extra or missing pulses detected between consecu-
tive 58X reference pulses.
S Number of extra or missing teeth is greater than or
equal to 2 per revolution.
S Above condition is detected in 10 of 100 crankshaft
rotations.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Freeze Frame and Failure Records
buffer.
S A history DTC is stored.
Conditions for Clearing the MIL/DTCS The MIL will turn OFF after four consecutive igni-
tion cycles in which the diagnostic runs without a
fault.
S A history DTC will clear after 40 consecutive warm–
up cycles have occurred without a fault.
S The DTC(s) can be cleared using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for:
S Poor connection – Inspect the ECM harness and
connectors for improper mating, broken locks, im-
properly formed or damaged terminals, and poor
terminal–towire connections.
S Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, discon-
nect the ECM, turn the ignition ON and observe a
voltmeter connected to the 58X reference circuit at
the ECM harness connector while moving the con-
nectors and the wiring harnesses related to the
ECM. A change in voltage will indicate the location
of the fault.
S Reviewing the Failure Records vehicle mileage
since the diagnostic test last failed may help deter-
mine how often the condition that caused the DTC
to be set occurs. This may assist in diagnosing the
condition.

ENGINE CONTROLS 1F – 453
DAEWOO V–121 BL4
DTC P0336 – 58X Crank Position Sensor Extra/Missing Pulses
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Was the check performed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
2Attempt to start the engine.
Does the engine start?–Go to Step 3Go to
”Engine Cranks
But Will Not
Run”
31. Turn the ignition OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Turn the ignition ON, with the engine OFF.
4. Review and record Failure Records informa-
tion.
5. Clear the Diagnostic Trouble Codes (DTCs).
6. Start the engine and idle for 1 minute.
Is DTC P0336 set?–Go to Step 4Go to
”Diagnostic
Aids”
41. Turn the ignition OFF.
2. Disconnect the Engine Control Module (ECM)
connector and Crankshaft Position (CKP) sen-
sor.
3. Check for an open or short to ground in the
58X reference circuit between CKP sensor
connector and the ECM harness connector.
Is a problem found?–Go to Step 5Go to Step 6
5Repair an open or short to ground in the 58X refer-
ence circuit between the CKP sensor connector and
the ECM harness connector.
Is the repair complete?–Go to Step 11–
6Reconnect the ECM and CKP sensor.
Connect a voltmeter to measure the voltage at termi-
nal M21 of the ECM connector.
Observe the voltage while cranking the engine.
Is the voltage near the specified value?1.6 vGo to Step 9Go to Step 7
7Check the connections at CKP sensor and repair or
replace the terminals.
Is the repair complete?–Go to Step 11Go to Step 8
81. Turn the ignition OFF.
2. Replace the CKP sensor.
Is the repair complete?–Go to Step 11–
9Check the connections at ECM and repair or replace
the terminals.
Is the repair complete?–Go to Step 11Go to Step 10
101. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 11–

ENGINE CONTROLS 1F – 455
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0337
58X CRANK POSITION SENSOR NO SIGNAL
Circuit Description
The 58X reference signal is produced by the Crankshaft
Position (CKP) sensor. During one crankshaft revolution,
58 crankshaft pulses will be produced. The Engine Control
Module (ECM) uses the 58X reference signal to calculate
engine rpm and CKP. The ECM constantly monitors the
number of pulses on the 58X reference circuit and
compares them to the number of Camshaft Position
(CMP) signal pulses being received. If the ECM does not
receive any 58X reference pulses on the 58X reference
circuit while cranking, Diagnostic Trouble Code (DTC)
P0337 will set.
Conditions for Setting the DTC
S 58X reference pulse not seen during cranking.
S DTCs P0341 and P0342 are not set.
S Change in voltage drop is greater than 0.5 volts and
change in Manifold Absolute Pressure (MAP) is
greater than 0.05kPa (0.07 psi).
S 58X reference pulse not seen for 0.078 seconds.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illumi-
nate.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Freeze Frame and Failure Records
buffer.
S A history DTC is stored.
Conditions for Clearing the MIL/DTCS The MIL will turn OFF after four consecutive igni-
tion cycles in which the diagnostic runs without a
fault.
S A history DTC will clear after 40 consecutive warm–
up cycles have occurred without a fault.
S The DTC(s) can be cleared using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for:
S Poor connection – Inspect the ECM harness and
connectors for improper mating, broken locks, im-
properly formed or damaged terminals, and poor
terminal–towire connections.
S Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, discon-
nect the ECM, turn the ignition ON and observe a
voltmeter connected to the 58X reference circuit at
the ECM harness connector while moving the con-
nectors and the wiring harnesses related to the
ECM. A change in voltage will indicate the location
of the fault.
S Reviewing the Failure Records vehicle mileage
since the diagnostic test last failed may help deter-
mine how often the condition that caused the DTC
to be set occurs. This may assist in diagnosing the
condition.

1F – 456IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0337 – 58X Crank Position Sensor No Signal
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Was the check performed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Start the engine.
4. Operate the vehicle within the Freeze Frame
conditions and Conditions for Setting the DTC
as noted.
Is Diagnostic Trouble Code (DTC) P0337 set?–Go to Step 3Go to Step 10
31. Turn the ignition OFF.
2. Disconnect the Crankshaft Position (CKP) sen-
sor connector.
3. Turn the ignition ON.
4. Using a voltmeter, check the voltage between
the CKP sensor wiring harness connector (En-
gine Control Module [ECM] side) terminal 1
and ground.
Does the voltage within the value specified?1.4 voltsGo to Step 4Go to Step 5
4Using a voltmeter, check the voltage between the
CKP sensor wiring harness connector (ECM side)
terminal 2 and ground.
Does the voltage within the value specified?1.4 voltsGo to Step 6Go to Step 5
51. Turn the ignition OFF.
2. Disconnect the ECM connector.
3. Turn the ignition ON.
4. Using a voltmeter, check the out put voltage of
the ECM terminal M21 and M5.
Does the voltage within the value specified?11–14 voltsGo to Step 8Go to Step 9
61. Reconnect the CKP sensor.
2. Using a voltmeter, back probe the ECM con-
nector terminal M21 and M5.
3. Observe the voltage while cranking the engine.
Does the voltage fluctuate between the specified
value?1.3–1.6 voltsGo to
”Diagnostic
Aids”Go to Step 7
71. Turn the ignition OFF.
2. Replace the CKP sensor.
Is the repair complete?–Go to Step 10–
8Check the CKP sensor high and low circuits for an
open, short to ground or voltage and repair as need-
ed.
Is the repair complete?–Go to Step 10–
91. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 10–

1F – 458IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0341
CAMSHAFT POSITION SENSOR RATIONALITY
System Description
The Camshaft Position (CMP) Sensor is used to correlate
crankshaft to camshaft position so that the Engine Control
Module (ECM) can determine which cylinder is ready to be
fueled by the injector. The CMP is also used to determine
which cylinder is misfiring when a misfire is present. When
the ECM cannot use the information from the CMP sensor,
a Diagnostic Trouble Code (DTC) is set, and the ECM will
fuel the engine using the Alternating Synchronous Double
Fire (ASDF) method.
Conditions for Setting the DTC
S CMP Sensor reference pulse is not detected at the
correct interval every 4 cylinders.
S Engine is running.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Freeze Frame and Failure Records
buffers.
S A history DTC is stored.Conditions for Clearing the MIL/DTC
S The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An intermittent problem may be caused by a poor connec-
tion, rubbed–through wire insulation, or a wire that is bro-
ken inside the insulation.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions:
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
S Physical damage to the wiring harness
Anytime a poor connection is present, the CMP Reference
Activity counter will stop incrementing.