change time DAEWOO LACETTI 2004 Service User Guide
[x] Cancel search | Manufacturer: DAEWOO, Model Year: 2004, Model line: LACETTI, Model: DAEWOO LACETTI 2004Pages: 2643, PDF Size: 80.54 MB
Page 346 of 2643

1F – 100IENGINE CONTROLS
DAEWOO V–121 BL4
ENGINE COOLING FAN CIRCUIT CHECK – DUAL FAN
(1.8L DOHC)
Circuit Description
The engine cooling fan circuit operates the main cooling
fan and the auxiliary cooling fan. The cooling fans are con-
trolled by the engine control module (ECM) based on in-
puts from the Engine Coolant Temperature (ECT) sensor
and the Air Conditioning Pressure (ACP) sensor. The
ECM controls the low speed cooling fan operation by inter-
nally grounding the ECM connector terminal K28. This en-
ergizes the low speed cooling fan relay and operates the
main cooling fan and the auxiliary cooling fan at low speed
as the cooling fans are connected in a series circuit. The
ECM controls the high speed cooling fan operation by in-
ternally grounding the ECM connector terminal K28 and
the ECM connector terminal K12 at the same time. This
energizes the low speed cooling fan relay, the high speed
cooling fan relay, and the series/parallel cooling fan relay
resulting in high speed fan operation as the cooling fans
are now connected in a parallel circuit.
Diagnostic Aids
S If the owner complained of an overheating problem,
it must be determined if the complaint was due to
an actual boil over, or the engine coolant tempera-
ture gauge indicated overheating. If the engine is
overheating and the cooling fans are on, the cooling
system should be checked.
S If the engine fuse block fuses Ef21, Ef6, Ef8 be-
come open (blown) immediately after installation,
inspect for a short to ground in the wiring of the ap-
propriate circuit. If the fuses become open (blown)
when the cooling fans are to be turned on by the
ECM, suspect a faulty cooling fan motor.
S The ECM will turn the cooling fans on at low speed
when the coolant temperature is 97°C (207°F). The
ECM will turn the cooling fans off when the coolant
temperature is 94°C(201°F).
S The ECM will turn the cooling fans on at high speed
when the coolant temperature is 101°C (214°F).
The ECM will change the cooling fans from high
speed to low speed when the coolant temperature
is 98°C (208°F).S The ECM will turn the cooling fans on at low speed
when the A/C system is on. The ECM will change
the cooling fans from low speed to high speed
when the high side A/C pressure is 1882 kPa (273
psi) then return to low speed when the high side
A/C pressure is 1448 kPa (210 psi). When the A/C
system is on, the ECM will change the cooling fans
from low to high speed when the coolant tempera-
ture reaches 117°C (244°F) then return to low
speed when the coolant temperature reaches
11 4°C (237°F).
S The cooling fan circuit can be checked quickly by
disconnecting the ECM connector 2 and grounding
the connector terminal K28. This should create low
speed cooling fan operation with the ignition ON. By
grounding the ECM connector terminals K28 and
K12 and turning the ignition ON, high speed cooling
fan operation should be achieved.
Test Description
The number(s) below refer to step(s) on the diagnostic
table.
4. This step, along with step 5, checks for the ability of
the ECM to operate the cooling fans.
8. This step, along with step 9, checks for the ability of
the ECM to operate the cooling fans in response to
A/C pressure readings.
16. After confirming battery voltage and the ECM sup-
plying a ground to the coil side of the cooling fan
relay A, by jumpering connector terminals 30 and
87 it will be determined if the relay is at fault or a
wiring problem is present.
31. This step checks for the presence of battery volt-
age to the main cooling fan when the A/C is on. If
battery voltage is present and the cooling fans are
not operating, the problem is in the ground side of
the cooling fan circuit.
37. By directly grounding the ECM connector terminals
K28 and K12, the main and auxiliary cooling fans
should run at high speed.
Engine Cooling Fan Circuit Check – Dual Fan (1.8L DOHC)
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) system
check.
Is the check completed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Check the I/P fuse block fuse F2.
2. Replace the fuse as needed.
Is the fuse OK?–Go to Step 3Go to
”Diagnostic
Aids”
Page 360 of 2643

1F – 114IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0107
MANIFOLD ABSOLUTE PRESSURE SENSOR LOW
VOLTAGE
Circuit Description
The engine control module (ECM) uses the Manifold Ab-
solute Pressure (MAP) sensor to control the fuel delivery
and the ignition timing. The MAP sensor measures the
changes in the intake manifold pressure, which results
from engine load (intake manifold vacuum) and the rpm
changes; and converts these into voltage outputs. The
ECM sends a 5 volt–reference voltage to the MAP sensor.
As the manifold pressure changes, the output voltage of
the MAP sensor also changes. By monitoring the MAP
sensor output voltage, the ECM knows the manifold pres-
sure. A low–pressure (low voltage) output voltage will be
about 1.0 to 1.5 volts at idle, while higher pressure (high
voltage) output voltage will be about 4.5 to 4.8 at wide
open throttle (WOT). The MAP sensor is metric pressure,
allowing the ECM to make adjustments for different alti-
tudes.
Conditions for Setting the DTC
S This DTC can be stored in ”key–on” status.
(Case A)
S When the engine idling.
S No throttle position(TP) sensor MTIA fail conditions
present.
S Engine speed(rpm) is less than 2,500rpm.
S The MAP is less than 12.0 kPa.
(Case A)
S When the engine part load.
S The engine revolution speed is less than 4,000rpm.S No Throttle Position (TP) Sensor fails conditions
present.
S The Throttle Position (TP) angle greather than
30.0°.
S The MAP is less than 11.5 kPa.
S An open or low voltage condition exists.
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
buffers.
S A history DTC is stored.
S The coolant fan turns ON.
S The ECM will substitutes a fixed MAP value and
use TP to control the fuel delivery (the scan tool will
not show defaulted)
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
With the ignition ON and the engine stopped, the manifold
pressure is equal to atmosphere pressure and the signal
voltage will be high.
Page 363 of 2643

ENGINE CONTROLS 1F – 117
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0108
MANIFOLD ABSOLUTE PRESSURE SENSOR HIGH
VOLTAGE
Circuit Description
The engine control module (ECM) uses the Manifold Ab-
solute Pressure (MAP) sensor to control the fuel delivery
and the ignition timing. The MAP sensor measures the
changes in the intake manifold pressure, which results
from engine load (intake manifold vacuum) and the rpm
changes; and converts these into voltage outputs. The
ECM sends a 5 volt–reference voltage to the MAP sensor.
As the manifold pressure changes, the output voltage of
the MAP sensor also changes. By monitoring the MAP
sensor output voltage, the ECM knows the manifold pres-
sure. A low–pressure (low voltage) output voltage will be
about 1.0 to 1.5 volts at idle, while higher pressure (high
voltage) output voltage will be about 4.5 to 4.8 at wide
open throttle (WOT). The MAP sensor is metric pressure,
allowing the ECM to make adjustments for different alti-
tudes.
Conditions for Setting the DTC
S This DTC can be stored in ”key–on” status.
S When the engine idling.
S Engine speed is greater than 700rpm.
S No throttle position sensor (TPS) fail conditions
present.
S The MAP is greater than 95kPA.
S A high voltage condition exists.
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
buffers.S A history DTC is stored.
S The ECM will substitutes a fixed MAP value and
use TP to control the fuel delivery (the scan tool will
not show defaulted)
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
With the ignition ON and the engine stopped, the manifold
pressure is equal to atmosphere pressure and the signal
voltage will be high.
The ECM as an indication of vehicle altitude uses this in-
formation. Comparison of this reading with a known good
vehicle with the same sensor is a good way to check the
accuracy of a suspect sensor. Readings should be the
same ±0.4volt.
If a DTC P0108 is intermittent, refer to ”Manifold Absolute
Pressure Check” in this section for further diagnosis.
If the connections are OK monitor the manifold absolute
pressure(MAP) sensor signal voltage while moving re-
lated connectors and the wiring harness. If the failure is in-
duced, the display on the scan tool will change. This may
help to isolate the location of an intermittent malfunction.
Page 377 of 2643

ENGINE CONTROLS 1F – 131
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0122
THROTTLE POSITION SENSOR LOW VOLTAGE
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (05, 195). The charac-
teristics of the airflow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical bowdencable.
The throttle position sensor (TPS) provides a voltage sig-
nal that changes in relation to the throttle plate angle. The
signal voltage will vary from about nearly 5.0 V at idles to
about 0.2V to 0.4 V at wide–open throttle. The TPS is one
of the most important inputs used by the ECM for fuel con-
trol and other functions such as idle, wide open throttle,
deceleration enleanment, and acceleration enrichment.
Conditions for Setting the DTC
S TPS voltage is less than 0.3V.
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
buffers.
S A history DTC is stored.
S The coolant fan turns ON.
S The ECM will default to 20°C (68°F) for the first 60
seconds of the engine run time, and then 92 °C
(198 °F).
S The scan tool will not show the defaulted value.
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
If the DTC P0122 cannot be duplicated, the information in-
cluded in the Freeze Frame data can be useful. Use the
scan tool DTC information data to determine the status of
the DTC. If the DTC occurs intermittently, using the DTC
P0121 diagnostic table may help isolate the problem.
Page 380 of 2643

1F – 134IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0123
THROTTLE POSITION SENSOR HIGH VOLTAGE
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (05, 195). The charac-
teristics of the airflow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical bowdencable.
The throttle position sensor (TPS) provides a voltage sig-
nal that changes in relation to the throttle plate angle. The
signal voltage will vary from about nearly 5.0 V at idles to
about 0.2V to 0.4 V at wide–open throttle. The TPS is one
of the most important inputs used by the ECM for fuel con-
trol and other functions such as idle, wide open throttle,
deceleration enleanment, and acceleration enrichment.
Conditions for Setting the DTC
S TPS voltage is greater than 4.8V.
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
buffers.S A history DTC is stored.
S The coolant fan turns ON.
S The ECM will default to 20°C (68°F) for the first 60
seconds of the engine run time, and then 92 °C
(198 °F).
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
If the DTC P0123 cannot be duplicated, the information in-
cluded in the Freeze Frame data can be useful. Use the
scan tool DTC information data to determine the status of
the DTC. If the DTC occurs intermittently, using the DTC
P0121 diagnostic table may help isolate the problem.
With the ignition ON and the throttle at closed position the
voltage should read between 0.20 V and 0.90V and in-
crease steadily to over 4.5V at WOT.
DTCs P0123 and P0113 stored at the same time could be
the result of an open sensor ground circuit.
Page 404 of 2643

1F – 158IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0171
FUEL TRIM SYSTEM TOO LEAN
System Description
If the adaptation value threshold is permanently exceed-
ed, the deviation of the adaptive terms enables to detect
a slow default coming out. Two time counters (one for the
rich side and another one for the lean side) are increased
while the lambda controller exceeds the adaptation
thresholds. As soon as one of the time counters reaches
its maximum value, the error is detected.
The aim of this test is to simulate a failure that would result
in exceeding the adaptive terms. Two kinds of failure must
be created.
S A lean side deviation: P0171
S A rich side deviation : P0172
It is thus necessary to determine, for each kind of failure,
the limit good and the limit bad. For a given failure, mea-
sure the emission threshold until the legal emission
thresholds are exceeded.
Note that the problem is due to the emission thresholds re-
quired, it is not simple to disturb the system so that the
emission thresholds will be exceeded. The tuning has
been made thanks to a dedicated calibration but, as such
a procedure is not permitted by the regulation, it is neces-
sary to create some material malfunction (fuel pressure
regulator, fuel injector, air leakage...).
Conditions for Setting the DTC
S DTCs P0107, P0108, P0112, P0113, P0117,
P0118, P0122, P0123, P0131, P0132, P0337,
P0338, P0341, P0342, P0400, P1319, P1402,
P1404, P1405, P1671 and P1672 are not set.
S Coolant temperature is greater than 20°C (68°F).
(1.4L DOHC)
S Coolant temperature is greater than 80°C (176°F).
(1.6L DOHC)
S Manifold Absolute Pressure (MAP) is greater than
70 kPa (10.2 psi).
S System is in closed loop.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.
S The ECM will record operating conditions at the
time the diagnostic fail. 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 10 sec-
onds.
Diagnostic Aids
Important : After repairs, use the scan tool Fuel Trim Re-
set function to reset the long–term fuel trim to 128 (0%).
S Fuel pressure – The system will be lean if the pres-
sure is too low. It may be necessary to monitor fuel
pressure while driving the vehicle at various road
speeds and/or loads to confirm.
S Map sensor – An output that causes the ECM to
sense a lower than normal manifold pressure (high
vacuum) can cause the system to go lean. Discon-
necting the MAP sensor will allow the ECM to sub-
stitute a fixed (default) value for the MAP sensor. If
the lean condition is gone when the sensor is dis-
connected, substitute a known good sensor and
recheck.
S Fuel contamination – Water, in even small amounts,
near the in–tank fuel pump inlet can be delivered to
the injector. The water causes a lean exhaust and
can set DTC P0171.
Check for poor O2S or MAP sensor connection at the
ECM. Inspect the harness connectors 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
Inspect the wiring harness for damage. If the harness ap-
pears to be OK, observe the O2S display on the scan tool
while moving the connectors and the wiring harness re-
lated to the engine harness. A change in the display will
indicate the location of the fault.
Check the brake power booster check valve for possible
leaks.
Page 408 of 2643

1F – 162IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0172
FUEL TRIM SYSTEM TOO RICH
System Description
If the adaptation value threshold is permanently exceed-
ed, the deviation of the adaptive terms enables to detect
a slow default coming out. Two time counters (one for the
rich side and another one for the lean side) are increased
while the lambda controller exceeds the adaptation
thresholds. As soon as one of the time counters reaches
its maximum value, the error is detected.The aim of this
test is to simulate a failure that would result in exceeding
the adaptive terms. Two kinds of failure must be created.
S A lean side deviation: P0171
S A rich side deviation : P0172
It is thus necessary to determine, for each kind of failure,
the limit good and the limit bad. For a given failure, mea-
sure the emission threshold until the legal emission
thresholds are exceeded.Note that the problem is due to
the emission thresholds required, it is not simple to disturb
the system so that the emission thresholds will be exceed-
ed. The tuning has been made thanks to a dedicated cal-
ibration but, as such a procedure is not permitted by the
regulation, it is necessary to create some material mal-
function (fuel pressure regulator, fuel injector, air leak-
age...).
Conditions for Setting the DTC
S DTCs P0107, P0108, P0112, P0113, P0117,
P0118, P0122, P0123, P0131, P0132, P0337,
P0338, P0341, P0342, P0400, P1319, P1402,
P1404, P1405, P1671 and P1672 are not set.
S Coolant temperature is greater than 20°C (68°F).
(1.4L DOHC)
S Coolant temperature is greater than 80°C (176°F).
(1.6L DOHC)
S Manifold Absolute Pressure (MAP) is greater than
70 kPa (10.2 psi).
S System is in closed loop.
Action Taken When the DTC SetsS The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.
S The ECM will record operating conditions at the
time the diagnostic fail. 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 10 sec-
onds.
Diagnostic Aids
Important : After repairs, use the scan tool Fuel Trim Re-
set function to reset the long–term fuel trim to 128 (0%).
Check for poor connection at the ECM. Inspect the har-
ness connectors 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.
Inspect the wiring harness for damage. If the harness ap-
pears to be OK, observe the O2S display on the scan tool
while moving the connectors and the wiring harness re-
lated to the engine harness. A change in the display will
indicate the location of the fault.
If a DTC P1404 is also set, check the 5 volt reference cir-
cuits for a short to voltage.
Check for a restricted exhaust system.
A shorted 5 volt reference circuit may cause a DTC P0172
to set. Check the 5 volt reference sensors for abnormal
readings.
DTC P0172 – Fuel Trim System Too Rich
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Install the scan tool to the Data Link Connector
(DLC).
2. Turn the ignition ON.
Are any component related Diagnostic Trouble
Codes (DTCs) set?–Go to
applicable DTC
tableGo to Step 3
Page 411 of 2643

ENGINE CONTROLS 1F – 165
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0222
MAIN THROTTLE IDLE ACTUATOR (MTIA) LOW VOLTAGE
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (05, 22.55). The char-
acteristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical bowdencable.
The throttle position sensor (TPS) provides a voltage sig-
nal that changes in relation to the throttle plate angle. The
signal voltage will vary from about nearly 5.0 V at idle to
about 0.2 V to 0.4 V at wide open throttle. The TPS is one
of the most important inputs used by the ECM for fuel con-
trol and other functions such as idle, wide open throttle,
deceleration enleanment, and acceleration enrichment.
Conditions for Setting the DTC
S MTIA voltage is less than 0.275V.
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 Records buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn off after 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 10 sec-
onds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
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 Damaged terminals
S Poor terminals to wire connection
S Physical damage to the wiring harness
Page 414 of 2643

1F – 168IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0223
MAIN THROTTLE IDLE ACTUATOR (MTIA) HIGH
VOLTAGE
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (05, 22.55). The char-
acteristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical bowdencable.
The throttle position sensor (TPS) provides a voltage sig-
nal that changes in relation to the throttle plate angle. The
signal voltage will vary from about nearly 5.0 V at idle to
about 0.2 V to 0.4 V at wide open throttle. The TPS is one
of the most important inputs used by the ECM for fuel con-
trol and other functions such as idle, wide open throttle,
deceleration enleanment, and acceleration enrichment.
Conditions for Setting the DTC
S MTIA voltage is higher than 4.9V.
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 Records buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn off after 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 10 sec-
onds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
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 Damaged terminals
S Poor terminals to wire connection
S Physical damage to the wiring harness
Page 447 of 2643

ENGINE CONTROLS 1F – 201
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0335
MAGNETIC CRANKSHAFT POSITION SENSOR
ELECTRICAL ERROR
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 transaxle con-
trol module(TCM)/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 (CKP) signal pulses being received.
If the ECM receive and incorrect number of pulses on the
58X reference circuit, DTC P0335 will set.
Conditions for Setting the DTC
S The magnetic crankshaft position sensor is greater
than 0.2V.
Or
S The minimum value of magnetic crankshaft position
sensor is less than 1.5V.
Or
S The maximum value of magnetic crankshaft posi-
tion sensor is higher than 2.2V.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.
S The ECM will record operating conditions at the
time the diagnostic fail. 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 may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for :
Poor connection – inspect the ECM harness and connec-
tors for improper mating, broken locks, improperly formed
or damaged terminals, and poor terminal–to–wire connec-
tion.
Damaged harness – inspect the wiring harness for dam-
age. If the harness appears to be OK, disconnect the
ECM, turn the ignition ON and observe a voltmeter con-
nected to the 58X reference circuit at the ECM harness
connector while moving the connectors and the wiring har-
ness related to the ECM. A change in voltage will indicate
the location of the fault.
Review the failure records vehicle mileage since the diag-
nostic test failed may help determine how often the condi-
tion that caused the DTC to be set occurs. This may assist
in diagnosing the condition.