2004 DAEWOO LACETTI sensor

ENGINE CONTROLS 1F – 235
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0445
EVAP PURGE CONTROL CIRCUIT FAULT
Circuit Description
The evaporative emission (EVAP) system includes the fol-
lowing components :
S Fuel tank.
S EVAP vent solenoid.
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 canister purge valve.
S EVAP service port.
The evaporative emission system is checked by applying
vacuum to the EVAP system and monitoring for a vacuum
decay. The engine control module(ECM) monitors the
vacuum level through the fuel tank pressure sensor signal.
At the appropriate time, the EVAP canister purge valve
and the EVAP vent solenoid are turned on, allowing the en-
gine to draw a small vacuum on the entire EVAP system.
After the desired vacuum level has been achieved, the
EVAP canister purge valve is turned OFF, sealing the sys-tem. If a sufficient vacuum level cannot be achieved, a
large leak is indicated. This can be caused by the following
conditions :
Missing or faulty fuel cap.
Disconnected or faulty fuel tank pressure sensor.
Disconnected, damaged, pinched, or blocked EVAP
purge line.
Disconnected or faulty EVAP canister purge valve.
Disconnected or faulty EVAP vent solenoid.
Open ignition feed circuit to the EVAP vent or purge sole-
noid.
Damaged EVAP canister.
Leaking fuel sensor assembly O–ring.
Leaking fuel tank or fuel filler beck.
Any of the above conditions can set DTC P0445.
The test is failed if the tank vacuum is less than 10 in H20
for 15 seconds and the manifold vacuum integral is greater
than 49512 (proportional to purge mass from the tank).
Conditions for Setting the DTC
S The canister purge solenoid valve circuit is a short
to battery or short to ground condition exist.

1F – 236IENGINE CONTROLS
DAEWOO V–121 BL4
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
Although this DTC is considered a type. A diagnostic, it
acts like a type B diagnostic under certain conditions.
Whenever this diagnostic reports the system has passed,
or if the battery is disconnected, the diagnostic must fail
twice before setting a DTC. The initial failure is not re-ported to the diagnostic executive or displayed on a scan
tool. A passing system always reports to the diagnostic
executive immediately.
Check for the following conditions :
S Missing or damaged fuel cap.
S Missing or damaged O–rings at fuel vapor and
EVAP purge line canister fittings.
S Cracked or punctured EVAP canister.
S Damaged source vacuum line, EVAP purge line,
EVAP vent hose or fuel tank vapor line.
S Poor 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.
S Damaged harness. Inspect the wiring harness to
the EVAP vent solenoid, EVAP canister purge
valve, and the fuel tank pressure sensor for an in-
termittent open or short circuit.
S Kinked, pinched or plugged vacuum source, EVAP
purge, or fuel tank vapor line. Verify that the lines
are not restricted.
DTC P0445 – EVAP Purge Control Circuit Fault
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. Disconnect the evaporative emission (EVAP)
canister purge valve connector.
2. Measure the resistance of the EVAP canister
purge valve connector.
Does the resistance measure near within the value
specified?30WGo to Step 3Go to Step 9
3Connect a test light between EVAP canister purge
valve connector terminal 2 and ground.
Is the test light ON?–Go to Step 4Go to Step 6
41. Disconnect the ECM connector.
2. Connect a test light between the ECM connec-
tor terminal 65 and ground.
Is the test light ON?–Go to Step 5Go to Step 7
51. Repair the high voltage or ground in the wire
between the EVAP canister purge valve con-
nector terminal 2 and the ECM connector ter-
minal 65.
2. Clear any Diagnostic Trouble Codes (DTCs)
from the ECM.
3. Perform the diagnostic system check.
Is the repair complete?–System OK–

1F – 238IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0462
FUEL LEVEL SENSOR LOW VOLTAGE (1.6L DOHC ONLY)
Circuit Description
The engine control module(ECM) uses the fuel level input
from the Fuel Level Sensor to calculate expected vapor
pressures within the fuel system. Vapor pressure vary as
the fuel level changes. Vapor pressure is critical in deter-
mining if the evaporative emission (EVAP) system is oper-
ating properly. Fuel Level is also used to determine if the
Fuel level is too high or too low to be able to accurately de-
tect EVAP system faults. This Diagnostic Trouble
Code(DTC) detects a stuck fuel level sender.
Conditions for Setting the DTC
S Fuel Level Sensor voltage is less than 0.2V.
S Fuel Level Sensor circuit low voltage.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.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 connectors for backed–out terminal, im-
proper mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connection.
Inspect the wiring harness for damage.
A stuck Fuel Level Sensor may cause the DTC to set. If
DTC P0463 cannot be duplicated, the information in-
cluded in the Freeze Frame data can be useful in deter-
mining vehicle operating conditions when the DTC was
first set.
Resistance check for the Fuel Level Sensor.
Empty = 100 ohms or over.
Half full = about 32.5 ohms.
Full = 10 ohms or less.

ENGINE CONTROLS 1F – 239
DAEWOO V–121 BL4
DTC P0462 – Fuel Level Sensor Low Voltage (1.6L DOHC Only)
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. Turn the ignition switch to ON.
2. Install a scan tool.
3. Operate the vehicle within Freeze Frame con-
ditions as noted.
Is the Diagnostic Trouble Code (DTC) P0462 set?–Go to Step 3Go to
”Diagnostic
Aids”
31. Disconnect the fuel sender electircal connector
from the fuel pump.
2. Using a digital voltmeter (DVM), measure the
voltage in the signal circuit at terminal 1.
Is the voltage within the specified value?0.2–4.8VGo to Step 4Go to Step 6
4Check for a proper ground connection at the fuel
tank and repair as necessary.
Is a repair necessary?–Go to Step 11Go to Step 5
51. Remove the fuel sender from the fuel tank.
2. Reconnect the fuel sender electrical connector.
3. Monitor the Fuel Level Sensor parameter on
the scan tool while moving the Fuel Level Sen-
sor float from the empty position to the full
position.
4. Repeat the procedure several times.
Does the Fuel Level Sensor value on the scan tool
increase 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 Lev-
el Sensor circuit and repair as necessary.
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 har-
ness connector and the Fuel Level Sensor.
Is the repair complete?–Go to Step 11–
8Replace the fuel sender assembly.
Is the replacement complete?–Go to Step 11–
91. Connect the fuel sender electrical connector.
2. Disconnect the engine control module(ECM)
connector.
3. Using a digital voltmeter (DVM) measure the
voltage in the signal circuit, at terminal 46.
Does the DVM read within the specified value?0.2–4.8VGo to Step 10Go to
Section 9E, In-
strumentation/
Driver Informa-
tion
10Replace the ECM.
Is the repair complete?–Go to Step 11–

ENGINE CONTROLS 1F – 241
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0463
FUEL LEVEL SENSOR HIGH VOLTAGE
(1.6L DOHC ONLY)
Circuit Description
The engine control module(ECM) uses the fuel level input
from the Fuel Level Sensor to calculate expected vapor
pressures within the fuel system. Vapor pressure vary as
the fuel level changes. Vapor pressure is critical in deter-
mining if the evaporative emission (EVAP) system is oper-
ating properly. Fuel Level is also used to determine if the
Fuel level is too high or too low to be able to accurately de-
tect EVAP system faults. This Diagnostic Trouble
Code(DTC) detects a stuck fuel level sender.
Conditions for Setting the DTC
S Fuel Level Sensor voltage is higher than 4.8V.
S Fuel Level Sensor circuit high voltage.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.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 connectors for backed–out terminal, im-
proper mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connection.
Inspect the wiring harness for damage.
A stuck Fuel Level Sensor may cause the DTC to set. If
DTC P0463 cannot be duplicated, the information in-
cluded in the Freeze Frame data can be useful in deter-
mining vehicle operating conditions when the DTC was
first set.
Resistance check for the Fuel Level Sensor.
Empty = 100 ohms or over.
Half full = about 32.5 ohms.
Full = 10 ohms or less.

1F – 242IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0463 – Fuel Level Sensor High Voltage (1.6L DOHC Only)
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. Turn the ignition switch to ON.
2. Install a scan tool.
3. Operate the vehicle within Freeze Frame con-
ditions as noted.
Is the Diagnostic Trouble Code (DTC) P0463 set?–Go to Step 3Go to
”Diagnostic
Aids”
31. Disconnect the fuel sender electircal connector
from the fuel pump.
2. Using a digital voltmeter (DVM), measure the
voltage in the signal circuit at terminal 1.
Is the voltage within the specified value?0.2–4.8VGo to Step 4Go to Step 6
4Check for a proper ground connection at the fuel
tank and repair as necessary.
Is a repair necessary?–Go to Step 11Go to Step 5
51. Remove the fuel sender from the fuel tank.
2. Reconnect the fuel pump electrical connector.
3. Monitor the Fuel Level Sensor parameter on
the scan tool while moving the Fuel Level Sen-
sor float from the empty position to the full
position.
4. Repeat the procedure several times.
Does the Fuel Level Sensor value on the scan tool
increase and then decrease steadily when the float
is moved?–Go to
”Diagnostic
Aids”Go to Step 8
6Check for an open or short to battery voltage in the
Fuel Level Sensor circuit and repair as necessary.
Is the repair necessary?–Go to Step 11Go to Step 9
7Repair the open or short to battery voltage in the
Fuel Level Sensor circuit between the Fuel Level
Sensor harness connector and the Fuel Level Sen-
sor.
Is the repair complete?–Go to Step 11–
8Replace the fuel sender assembly.
Is the replacement complete?–Go to Step 11–
91. Connect the fuel sender electrical connector.
2. Disconnect the engine control module(ECM)
connector.
3. Using a digital voltmeter (DVM) measure the
voltage in the signal circuit, at terminal 46.
Does the DVM read within the specified value?0.2–4.8VGo to Step 10Go to
Section 9E, In-
strumentation/
Driver Informa-
tion
10Replace the ECM.
Is the repair complete?–Go to Step 11–

ENGINE CONTROLS 1F – 257
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0501
VEHICLE SPEED NO SIGNAL (M/T ONLY)
Circuit Description
Vehicle speed information is provided to the engine control
module (ECM) by the voltage speed sensor (VSS) is a per-
manent magnet generator that is mounted in the transaxle
and produces a pulsing voltage whenever vehicle speed
is over 3 mph (5km/h). The A/C voltage level and the num-
ber of pulses increase with vehicle speed. The ECM con-
verts the pulsing voltage into mph (km/h) and than sup-
plies the necessary signal to the instrument panel for
speedometer/ odometer operation and to the cruise con-
trol module and multi–function alarm module operation.
The Diagnostic Trouble Code (DTC) will detect if vehicle
speed is reasonable according to engine rpm and load.
Conditions for Setting the DTC
S Vehicle speed is not change at least 25 seconds.
S Engine speed is greater than 2,500rpm.
S MAF is greater than 180mg/tdc.
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 Coolant fan turns on.
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 Using the scan tool can clear DTC(s).
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.
VSS signal circuit should be thoroughly checked for the
following conditions
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed

1F – 258IENGINE CONTROLS
DAEWOO V–121 BL4
S Damaged terminals
S Poor terminal to wire connection
S Physical damage to the wiring harness
Ensure the VSS is correctly torqued to the trnasaxle hous-ing.
Refer to ”Intermittents” in this section.
DTC P0501 – Vehicle Speed No Signal (M/T Only)
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”
2Notice : Running the vehicle in gear with the wheels
hanging down at full travel will damage the drive
axles.
1. Turn the ignition ON, with the engine OFF.
2. Install a scan tool.
3. Raise the drive wheels.
4. Support the lower control arms so that the
drive axles are in a horizontal (straight) posi-
tion.
5. Allow the engine to idle in gear.
Does the scan tool display vehicle speed above the
specified value?0 mphGo to Step 3Go to Step 4
31. Turn the ignition ON, with the engine OFF.
2. Review the Freeze Frame data and note the
parameters.
3. Operate the vehicle within the Freeze Frame
conditions and Conditions for Setting this DTC.
Does the scan tool display the vehicle speed above
the specified value?0 mphGo to Step 12Go to Step 4
41. Turn the ignition OFF.
2. Disconnect the engine control module(ECM)
connector 51.
3. Using a digital voltmeter(DVM) connected to
ground, measure the voltage in the Vehicle
Speed Sensor (VSS) signal circuit, at terminal
C while rotating the wheels.
Is the voltage greater than or eqaul to specified val-
ue?0.5VGo to Step 12Go to Step 5
5Measure the resistant in the VSS signal circuit while
rotating the wheels.
Is the resistance greater than the specified value?1950WGo to Step 6Go to Step 7
6Check the VSS signal circuit for an open and repair
as necessary.
Is the repair complete?–Go to Step 12Go to Step 9
7Is the resistance value within or equal to the speci-
fied value?1300–1950WGo to Step 8Go to Step 9
8Check the VSS signal circuit for a short to ground or
for being shorted together and repair as necessary.
Is a repair necessary?–Go to Step 12Go to Step 12
91. Remove the VSS.
2. Measure the resistance between terminals A
and C.
Is the resistance value within the specified value?1300–1950WGo to Step 11Go to Step 10