2004 DAEWOO LACETTI sensor

ENGINE CONTROLS 1F – 485
DAEWOO V–121 BL4
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 any component DTCs are set, diagnose those
DTCs first. A fault in a component can cause the
converter to appear degraded or may have caused
its failure.
3. This step includes checks for conditions that can
cause the three–way catalytic converter to appear
degraded. Repair any problems found before pro-
ceeding with this table.
5. If the three–way catalytic converter needs to be
replaced, make sure that another condition is not
present which would cause the converter to be-
come damaged. These conditions may include thefollowing: misfire, high engine oil or coolant con-
sumption, and/or retarded spark timing or weak
spark. To avoid damaging the replacement convert-
er, correct any possible causes of converter dam-
age before replacing the catalytic converter.
6. Clearing DTCs allows the catalyst test to be run up
to 6 times this ignition cycle. Once the ignition is
cycled, the test will run only once. Driving the ve-
hicle heats the catalyst to a test temperature. The
ECM must see predetermined amount of time at
above idle before allowing the catalyst test to run at
idle. Once at idle, the ECM will allow the system to
stabilize and then test the catalyst in 2 stages.
7. If no faults have been found at this point and no
additional DTCs were set, refer to ”Diagnostic Aids”
in this section for additional checks and informa-
tion.
DTC P0420 – Catalyst Oxygen Sensor Low Efficiency
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”
2S Install a scan tool to the Data Link Connector
(DLC).
S Turn the ignition ON.
Are any component Diagnostic Trouble Codes
(DTCs) set?–Go to
applicable DTC
tablesGo to Step 3
3Visually/physically check the following:
S Exhaust system for a leak.
S Rear Heated Oxygen Sensor (HO2S2)
Is a problem found?–Go to Step 4Go to Step 5
4Repair the exhaust system as needed.
Is the repair complete?–Go to Step 6–
5Replace the Three Way Catalytic Converter (TWC).
Is the repair complete?–Go to Step 6–
61. 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 this DTC as specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run 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

1F – 486IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0443
EVAPORATIVE EMISSION SYSTEM PURGE SOLENOID
CONTROL CIRCUIT
System Description
The Evaporative Emission (EVAP) system includes the
following components:
S Fuel tank
S Fuel tank pressure sensor.
S Fuel pipes and hoses.
S Fuel vapor lines.
S Fuel cap
S EVAP canister.
S Purge lines.
S EVAP emission canister purge solenoid valve.
S EVAP service port.
The EVAP purge canister solenoid is controlled by the En-
gine Control Module (ECM). The ECM applies a ground to
the EVAP purge canister solenoid. The ECM determines
when to activate the EVAP canister purge solenoid de-
pending on operating conditions, including Throttle Posi-
tion (TP), engine speed, Engine Coolant Temperature
(ECT) and ambient temperature.
The Diagnostic Trouble Code will detect an open or short
circuit.
Conditions for Setting the DTC
S Ignition ON.
S Ignition voltage is greater than 11 v.
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 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 a scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
Using Freeze Frame and/or Failure Records data may aid
in locating an intermittent condition. If the DTC cannot be
duplicated, the information included in the Freeze Frame
and/or Failure Records data can be useful in determining
how many miles since the DTC set. The Fail Counter and
the Pass Counter can also be used to determine how
many ignition cycles the diagnostic reported a pass and/or
a fail. Operate the vehicle within the same freeze frame
conditions (rpm, load, vehicle speed, temperature, etc.)
that were noted. This will isolate when the DTC failed.

ENGINE CONTROLS 1F – 489
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0461
FUEL LEVEL STUCK
Circuit Description
The Engine Control Module (ECM) uses the signal from
the fuel level sensor to calculate expected vapor pressure
within the fuel system. Vapor pressure varies as the fuel
level changes. The fuel level signal also used to determine
if the fuel level is too high or too low to be able to detect
Evaporative Emission (EVAP) system faults. This Diag-
nostic Trouble Code (DTC) indicates the fuel level stuck.
Conditions for Setting the DTC
S Change in fuel level sensor output is less than 3.5%
after 250 km (155 mile) driving.
S Ignition ON.
S DTCs P0462, P0463 and P0502 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 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
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
rubber.
Check for a poor connection or damaged ECM harness.
Inspect the fuel level circuit terminal for the following con-
ditions:
S Improper mating.
S Broken locks.
S Improperly formed.
S Damaged terminals.
S Poor terminal–to–wire connection.
S Damaged harness.
Test Description
The number(s) below refer to step(s) on the diagnostic
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
2. Determine if fault is present. Reviews Freeze
Frame data to determine when the DTC set. Al-
ways record this information.

1F – 490IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0461 – Fuel Level Stuck
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Install a scan tool to the Data Link Connector
(DLC).
2. Start the engine and operate the vehicle over
the specified mileage.
Is any of the Diagnostic trouble Codes (DTCs)
P0462, P0463 or P0502 set?250 km
(155 mile)Go to Applica-
ble DTC tableGo to Step 3
31. Turn the ignition OFF.
2. Disconnect the fuel pump connector.
3. Turn the ignition ON.
4. Using a voltmeter, measure the fuel level signal
voltage at the fuel level sensor connector ter-
minal 1.
Is the voltage within the specified value?4–5 voltsGo to Step 4Go to Step 5
41. Disconnect the Engine Control Module (ECM).
2. Check the fuel level sensor ground circuit for
an open between terminal 6 of the fuel sensor
connector and terminal K34 of the ECM and
repair as needed.
Is the repair complete?–Go to Step 10Go to Step 6
5Using a voltmeter, measure the voltage at the ECM
connector terminal K34 by back–probing the ECM
connector.
Is the voltage within the specified value?4–5 VGo to Step 8Go to Step 9
61. Remove the fuel pump from the fuel tank.
2. Reconnect the fuel pump connector.
3. Turn the ignition ON.
4. Monitor the fuel level sensor parameter on the
scan tool while moving the fuel sensor float
from empty position to full position.
5. Repeat procedure 4 several times.
Does the fuel level sensor vale on the scan tool in-
crease and then decrease steadily when the float is
moved?–Go to
”Diagnostic
Aids”Go to Step 7
71. Turn the ignition OFF.
2. Replace the fuel pump assembly.–Go to Step 10–
81. Turn the ignition OFF.
2. Disconnect the ECM connector.
3. Check the fuel level signal circuit fir an open or
short to ground between terminal K51 and fuel
pump harness connector terminal 1 and repair
as needed.
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 – 492IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0462
FUEL LEVEL LOW VOLTAGE
Circuit Description
The Engine Control Module (ECM) uses the signal from
the fuel level sensor to calculate expected vapor pressure
within the fuel system. Vapor pressure varies as the fuel
level changes. The fuel level signal also used to determine
if the fuel level is too high or too low to be able to detect
Evaporative Emission (EVAP) system faults. This Diag-
nostic Trouble Code (DTC) detects a continuous short to
low or open in either the signal circuit or the fuel level sen-
sor.
Conditions for Setting the DTC
S Fuel level sensor output is less than 5% of sensor
reading scale.
S Ignition ON.
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 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
Inspect harness connector for backed–out terminal, im-
proper mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connection.
Inspect wiring harness for damage.
A stuck fuel level sensor may cause the DTC set.
If the DTC P0462 cannot be duplicate, the information in-
cluded on the Failure record data can be useful in deter-
mine vehicle conditions when the DTC was first set.
Resistance checks for fuel level sensor:
S Empty = 280 ohms or over.
S Half Full = about 90 ohms.
S Full = 38 ohms or less
Test Description
The number(s) below refer to step(s) on the diagnostic
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. Determine if fault is present. Review Freeze Frame
data to determine when the DTC set. Always record
this information.

ENGINE CONTROLS 1F – 493
DAEWOO V–121 BL4
DTC P0462 – Fuel Level Low Voltage
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. Start the engine and operate the vehicle within
Failure Record condition as noted.
Is Diagnostic trouble Codes (DTCs) P0462 set?–Go to Step 3Go to
”Diagnostic
Aids”
31. Turn the ignition OFF.
2. Disconnect the fuel pump connector.
3. Turn the ignition ON.
4. Using a voltmeter, measure the fuel level signal
voltage at the fuel level sensor connector ter-
minal 1.
Is the voltage within the specified value?0.4 – 4.5 VGo to Step 4Go to Step 6
4Check for a proper ground connection at the fuel
tank and repair as needed.
Is the repair complete?–Go to Step 11Go to Step 5
51. Remove the fuel pump from the fuel tank.
2. Reconnect the fuel pump connector.
3. Turn the ignition ON.
4. Monitor the fuel level sensor parameter on the
scan tool while moving the fuel sensor float
from empty position to full position.
5. Repeat procedure 4 several times.
Does the fuel level sensor vale on the scan tool in-
crease and then decrease steadily when the float is
moved?–Go to
”Diagnostic
Aids”Go to Step 8
6Check for an open or short to ground in the fuel level
sensor circuit and repair as needed.
Is the repair necessary?–Go to Step 11Go to Step 9
7Repair the open or short to ground in the fuel level
sensor circuit between the fuel level sensor harness
connector and fuel level sensor.
Is the repair complete?–Go to Step 11–
81. Turn the ignition OFF.
2. Replace the fuel pump assembly.
Is the repair complete?–Go to Step 11–
91. Turn the ignition OFF.
2. Connect the fuel pump connector.
3. Disconnect the engine Control Module (ECM)
connector.
4. Turn the ignition ON.
5. Using a digital voltmeter, measure the voltage
in the signal circuit at terminal K51.
Is the voltage within the specified value?4–5 VGo to Step 10Go to
Section 9E, In-
strumentation/
Driver Informa-
tion
10S Turn the ignition OFF.
S Replace the ECM.
Is the repair complete?–Go to Step 11–

ENGINE CONTROLS 1F – 495
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0463
FUEL LEVEL HIGH VOLTAGE
Circuit Description
The Engine Control Module (ECM) uses the signal from
the fuel level sensor to calculate expected vapor pressure
within the fuel system. Vapor pressure varies as the fuel
level changes. The fuel level signal also used to determine
if the fuel level is too high or too low to be able to detect
Evaporative Emission (EVAP) system faults. This Diag-
nostic Trouble Code (DTC) detects a continuous short to
low or open in either the signal circuit or the fuel level sen-
sor.
Conditions for Setting the DTC
S Fuel level sensor output is greater than 85% of sen-
sor reading scale.
S Ignition ON.
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 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
Inspect harness connector for backed–out terminal, im-
proper mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connection.
Inspect wiring harness for damage.
A stuck fuel level sensor may cause the DTC set.
If the DTC P0462 cannot be duplicate, the information in-
cluded on the Failure record data can be useful in deter-
mine vehicle conditions when the DTC was first set.
Resistance checks for fuel level sensor:
S Empty = 280 ohms or over.
S Half Full = about 90 ohms.
S Full = 38 ohms or less.
Test Description
The number(s) below refer to step(s) on the diagnostic
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. Determine if fault is present. Review Freeze Frame
data to determine when the DTC set. Always record
this information.

1F – 496IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0463 – Fuel Level High Voltage
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. Start the engine and operate the vehicle within
Failure Record condition as noted.
Is Diagnostic trouble Codes (DTCs) P0463 set?–Go to Step 3Go to
”Diagnostic
Aids”
31. Turn the ignition OFF.
2. Disconnect the fuel pump connector.
3. Turn the ignition ON.
4. Using a voltmeter, measure the fuel level signal
voltage at the fuel level sensor connector ter-
minal 1.
Is the voltage within the specified value?0.4 – 4.5 VGo to Step 4Go to Step 6
4Check for a proper ground connection at the fuel
tank and repair as needed.
Is the repair necessary?–Go to Step 11Go to Step 5
51. Remove the fuel pump from the fuel tank.
2. Reconnect the fuel pump connector.
3. Turn the ignition ON.
4. Monitor the fuel level sensor parameter on the
scan tool while moving the fuel sensor float
from empty position to full position.
5. Repeat procedure 4 several times.
Does the fuel level sensor vale on the scan tool in-
crease and then decrease steadily when the float is
moved?–Go to
”Diagnostic
Aids”Go to Step 8
6Check for short to voltage in the fuel level sensor cir-
cuit and repair as needed.
Is the repair necessary?–Go to Step 7Go to Step 9
7Repair the short to voltage in the fuel level sensor cir-
cuit between the fuel level sensor harness connector
and fuel level sensor.
Is the repair necessary?–Go to Step 11–
8S Turn the ignition OFF.
S Replace the fuel pump assembly.
Is the repair complete? –Go to Step 11–
91. Turn the ignition OFF.
2. Connect the fuel pump connector.
3. Disconnect the engine Control Module (ECM )
connector.
4. Turn the ignition ON.
5. Using a digital voltmeter, measure the voltage
in the signal circuit at terminal K51.
Is the voltage within the specified value?0.4 – 4.5 VGo to Step 10Go to
Section 9E, In-
strumentation/
Driver Informa-
tion
10S Turn the ignition OFF.
S Replace the ECM.
Is the repair complete?–Go to Step 11–