engine electrical DAEWOO LACETTI 2004 Service Manual Online

1F – 228IENGINE CONTROLS
DAEWOO V–121 BL4
Diagnostic Aids
Due to moisture associated with exhaust systems, the
EGR valve may freeze and stick in cold weather at times.
After the vehicle is brought into a warm shop for repairs,
the valve warms and the problem disappears. By watchingthe Actual EGR and desired EGR positions on a cold ve-
hicle with a scan tool, the fault can be easily verified.
Check the Freeze Frame data to determine if the DTC set
when the vehicle was cold by viewing the Engine Coolant
Temperature (ECT).
DTC P0406 – EGR Pintle Position Sensor High Voltage
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 ON with the engine
OFF.
2. Install the scan tool.
3. Command the Exhaust Gas Recirculation
(EGR) valve to the specified values.
Does the Actual EGR Position follow the desired
EGR position?25%, 50%
75%, 100%Go to Step 14Go to Step 3
31. Turn the ignition switch ON with the engine
OFF.
2. Disconnect the EGR valve electrical connector.
3. With a Digital Voltmeter (DVM) connected to
ground, probe the 5 volt reference circuit at
terminal 1 to the EGR valve.
Does the DVM read near the specified value?5VGo to Step 4Go to Step 5
4Jumper the 5 volt reference circuit to the signal cir-
cuit at terminals 1 and 3.
Does the actual EGR position display the specified
value ?100%Go to Step 6Go to Step 7
51. Connect the test light to B+.
2. robe the 5 volt reference circuit to the EGR
valve.
Does the test light illuminate?–Go to Step 8Go to Step 9
6Check the 5 volt reference and signal circuit for a
poor connection or proper terminal tension and re-
pair as necessary.
Is a repair necessary?–Go to Step 14Go to Step 10
71. Connect the test light to ground.
2. Probe the signal circuit at terminal 3 to the
EGR valve.
Does the test light illuminate?–Go to Step 11Go to Step 13
8Check for a short to ground in the EGR valve 5 volt
reference circuit and repair as necessary.
Is a repair necessary?–Go to Step 14Go to Step 12
9Check for an open in the EGR valve 5 volt reference
circuit and repair as necessary.
Is a repair necessary?–Go to Step 14Go to Step 13
10Replace the EGR valve.
Is the action complete?–Go to Step 14–
11Check for a short to voltage in the EGR valve signal
circuit and repair as necessary.
Is a repair necessary?–Go to Step 14Go to Step 12

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–

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 – 271
DAEWOO V–121 BL4
DTC P0562 – System Voltage(Engine Side) Too Low
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 and clear the Diagnostic
Trouble Codes (DTCs).
2. Start the engine and raise the engine speed to
the specified value.
3. Load the electrical system by turning on the
headlights, high blower motor, etc.
Is the ignition voltage less than the specified value?1,400rpm 10VGo to Step 3Go to Step 8
31. With the engine still running at the specified
value.
2. Using a digital voltmeter(DVM), measure the
battery voltage at the battery.
Is the battery voltage greater than the specified val-
ue?1,400rpm 12VGo to Step 4Go to
”Diagnostic
Aids”
41. Turn the ignition switch to LOCK.
2. Disconnect the engine control module(ECM)
connector at the ECM.
3. Turn the Turn the ignition switch to ON with the
engine OFF.
4. Using a DVM, measure the ignition voltage at
the ignition feed circuit, terminal 29.
Is the ignition voltage greater than the specified val-
ue?10VGo to Step 5Go to Step 6
5Check for a malfunctioning connection at the ECM
harness terminals and repair as necessary.
Is a repair necessary?–Go to Step 8Go to Step 7
6Repair the poor connection (high resistance) in the
ignition feed circuit.
Is the repair complete?–Go to Step 8–
7Replace the ECM.
Is the replacement complete?–Go to Step 8–
81. 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 specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 9Go to Step 2
9Check 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 – 273
DAEWOO V–121 BL4
DTC P0563 – System Voltage(Engine Side) Too High
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 and clear the Diagnostic
Trouble Codes (DTCs).
2. Start the engine and raise the engine speed to
the specified value.
3. Load the electrical system by turning on the
headlights, high blower motor, etc.
Is the ignition voltage less than the specified value?1,400rpm 10VGo to Step 3Go to Step 8
31. With the engine still running at the specified
value.
2. Using a digital voltmeter(DVM), measure the
battery voltage at the battery.
Is the battery voltage greater than the specified val-
ue?1,400rpm 12VGo to Step 4Go to
”Diagnostic
Aids”
41. Turn the ignition switch to LOCK.
2. Disconnect the engine control module(ECM)
connector at the ECM.
3. Turn the Turn the ignition switch to ON with the
engine OFF.
4. Using a DVM, measure the ignition voltage at
the ignition feed circuit, terminal 29.
Is the ignition voltage greater than the specified val-
ue?10VGo to Step 5Go to Step 6
5Check for a malfunctioning connection at the ECM
harness terminals and repair as necessary.
Is a repair necessary?–Go to Step 8Go to Step 7
6Repair the poor connection (high resistance) in the
ignition feed circuit.
Is the repair complete?–Go to Step 8–
7Replace the ECM.
Is the replacement complete?–Go to Step 8–
81. 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 specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 9Go to Step 2
9Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

1F – 274IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0601
ENGINE CONTROL MODULE CHECKSUM ERROR
Circuit Description
The engine control module (ECM) is the control center of
the fuel injection system. It constantly looks at the informa-
tion from various sensors, and controls the systems that
after vehicle performance. The ECM also performs the
diagnostic function of the system. It can recognize opera-
tional problems, alert the driver through the Malfunction In-
dicator Lamp (MIL), and store a Diagnostic Trouble Code
(DTC) or DTCs which identify the problem areas to aid the
technician in making repairs. An electrically erasable pro-
grammable read only memory (EEPROM) is used to
house the program information and the calibrations re-
quired for engine, transaxle, transaxle diagnostics opera-
tion. The ECM uses a value called a checksum for error
detection of the software. The checksum is a value that is
equal to all the numbers in the software added together.
The ECM adds all the values in the software and if that val-
ue does not equal the checksum value, a checksum error
is indicated.Conditions for Setting the DTC
S The ECM detects incorrect checksum.
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
cycle 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.
DTC P0601 – Engine Control Module Checksum Error
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”
2Replace the engine control module(ECM).
Is the replacement complete?–Go to Step 3–
31. 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 ad specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 4Go to Step 2
4Check 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 – 275
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0604
ENGINE CONTROL MODULE INTERNAL/EXTERNAL RAM
ERROR
Circuit Description
The engine control module (ECM) is the control center of
the fuel injection system. It constantly looks at the informa-
tion from various sensors, and controls the systems that
after vehicle performance. The ECM also performs the
diagnostic function of the system. It can recognize opera-
tional problems, alert the driver through the Malfunction In-
dicator Lamp (MIL), and store a Diagnostic Trouble Code
(DTC) or DTCs which identify the problem areas to aid the
technician in making repairs. An electrically erasable pro-
grammable read only memory (EEPROM) is used to
house the program information and the calibrations re-
quired for engine, transaxle, transaxle diagnostics opera-
tion. The ECM uses a value called a checksum for error
detection of the software. The checksum is a value that is
equal to all the numbers in the software added together.
The ECM adds all the values in the software and if that val-
ue does not equal the checksum value, a checksum error
is indicated.
Conditions for Setting the DTCS The ECM detects an internal or external Random
Acess Memory (RAM) error.
Action Taken When the DTCs 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.
DTC P0604 – Engine Control Module Internal/External RAM Error
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”
2Replace the engine control module(ECM).
Is the replacement complete?–Go to Step 3–
31. 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 ad specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 4Go to Step 2
4Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

1F – 276IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0605
ENGINE CONTROL MODULE INMVY WRITE ERROR
Circuit Description
The engine control module (ECM) is the control center of
the fuel injection system. It constantly looks at the informa-
tion from various sensors, and controls the systems that
after vehicle performance. The ECM also performs the
diagnostic function of the system. It can recognize opera-
tional problems, alert the driver through the Malfunction In-
dicator Lamp (MIL), and store a Diagnostic Trouble Code
(DTC) or DTCs which identify the problem areas to aid the
technician in making repairs. An electrically erasable pro-
grammable read only memory (EEPROM) is used to
house the program information and the calibrations re-
quired for engine, transaxle, transaxle diagnostics opera-
tion. The ECM uses a value called a checksum for error
detection of the software. The checksum is a value that is
equal to all the numbers in the software added together.
The ECM adds all the values in the software and if that val-
ue does not equal the checksum value, a checksum error
is indicated.Conditions for Setting the DTC
S The ECM detects a INMVY write error.
Action Taken When the DTCs 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.
DTC P0605 – Engine Control Module INMVY Write Error
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”
2Replace the engine control module(ECM).
Is the replacement complete?–Go to Step 3–
31. 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 ad specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 4Go to Step 2
4Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

1F – 300IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P1382 – Rough Road Data Invalid (NON ABS)
StepActionValue(s)YesNo
1Perform an Euro 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 ON, with engine OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Review and record the scan tool Failure Re-
cords data.
4. Operate the vehicle within Failure Records
conditions as noted.
5. Using the scan tool, monitor specific Diagnostic
Trouble Code (DTC) info for DTC P1382.
Does the scan tool indicate that DTC P1382 failed?–Go to Step 4Go to Step 3
31. Check for the following conditions and repair as
needed:
2. VR sensor seal missing or damaged.
3. VR sensor mounting flanges cracked, missing,
or incorrectly installed.
Is the repair complete?–Go to Step 14Go to
”Diagnostic
Aids”
41. Turn the ignition OFF.
2. Disconnect the VR sensor electrical connector.
3. Turn the ignition ON, with the engine OFF.
4. Observe the VR sensor value displayed on the
scan tool.
Is the VR sensor value near the specified value?0VGo to Step 5Go to Step 12
51. Jumper the 5 volt reference circuit, terminal 2
and the VR sensor signal circuit, terminal 1 to-
gether at the VR sensor harness connector.
2. Observe the VR sensor value displayed on the
scan tool.
Is the VR sensor value near the specified value?4.95VGo to Step 14Go to Step 10
61. Turn the ignition OFF.
2. Disconnect the Engine Control Module (ECM)
and check the sensor ground circuit for high
resistance, an open between the ECM and the
VR sensor, or for a poor connection at the ter-
minal 53 of the ECM and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 10
7Check the 5 volt reference circuit for high resistance,
an open between the ECM and the VR sensor, or a
poor connection at the terminal 84 of the ECM and
repair as needed.
Is the repair complete?–Go to Step 14Go to Step 8
81. Turn the ignition OFF.
2. Disconnect the ECM and check the VR sensor
signal circuit for high resistance, an open, a low
voltage, or a short to the sensor ground circuit
and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 9

ENGINE CONTROLS 1F – 303
DAEWOO V–121 BL4
DTC P1382 – Rough Road Data Invalid (ABS)
StepActionValue(s)YesNo
1Perform an Euro 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 ON, with engine OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Review and record the scan tool Failure Re-
cords data.
4. Operate the vehicle within Failure Records
conditions as noted.
5. Using the scan tool, monitor specific Diagnostic
Trouble Code (DTC) info for DTC P1382.
Does the scan tool indicate that DTC P1382 failed?–Go to Step 4Go to Step 3
31. Check for the following conditions and repair as
needed:
2. Wheel speed sensor seal missing or damaged.
3. Wheel speed sensor mounting flanges
cracked, missing, or incorrectly installed.
Is the repair complete?–Go to Step 14Go to
”Diagnostic
Aids”
41. Turn the ignition OFF.
2. Disconnect the defected Wheel speed sensor
electrical connector.
3. Turn the ignition ON, with the engine OFF.
4. Observe the Wheel speed sensor value dis-
played on the scan tool.
Is the Wheel speed sensor value near the specified
value?0VGo to Step 5Go to Step 12
51. Jumper the 5 volt reference circuit, the Wheel
speed sensor signal circuit, together at the de-
fected Wheel speed sensor harness connector.
2. Observe the defected Wheel speed sensor val-
ue displayed on the scan tool.
Is the VR sensor value near the specified value?4.95VGo to Step 14Go to Step 10
61. Turn the ignition OFF.
2. Disconnect the Engine Control Module (ECM)
and check the sensor ground circuit for high
resistance, an open between the ECM and the
Wheel speed sensor, or for a poor connection
of the ECM and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 10
7Check the 5 volt reference circuit for high resistance,
an open between the ECM and the Wheel speed
sensor, or a poor connection of the ECM and repair
as needed.
Is the repair complete?–Go to Step 14Go to Step 8