ignition DAEWOO LACETTI 2004 Service Repair Manual

ENGINE CONTROLS 1F – 169
DAEWOO V–121 BL4
DTC P0223 – Main Throttle Idle Actuator (MTIA) 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. Connect the scan tool to the DLC.
2. Turn the ignition switch to ON.
3. Press the accelerator pedal while watching
TPS for smooth changes in the voltage.
Does the scan tool show the TPS voltage change
smoothly within the value specified?0.3V–4.8VGo to
”Diagnostic
Aids”Go to Step 3
31. Turn the ignition switch to LOCK.
2. Disconnect the MTIA connector.
3. Measure the voltage between terminal 1 and 5.
Does the voltage measure within the value speci-
fied?4.8–5.0VGo to Step 4Go to Step 5
4Connect a fused jumper between the MTIA connec-
tor terminal 1 and terminal 6.
Does the scan tool show the TPS voltage above val-
ue specified?More than
4.8–5.0VGo to Step 10Go to Step 8
5Measure the voltage between the MTIA connector
1 and ground.
Does the voltage measure within the value speci-
fied?Below 5.0VGo to Step 6Go to Step 7
61. Turn the ignition switch to LOCK.
2. Disconnect the engine control module(ECM).
3. Check for an open or short to battery voltage in
the wire between the MTIA connector 5 and
ECM connector 62.
Is the problem found?–Go to Step 9Go to Step 11
71. Turn the ignition switch to LOCK.
2. Check for an open or short to battery voltage in
the wire between the MTIA connector 1 and
ECM connector 61.
Is the problem found?–Go to Step 9Go to Step 11
81. Turn the ignition switch to LOCK.
2. Check for an open or short to battery voltage in
the wire between the MTIA connector 6 and
ECM connector 55.
Is the problem found?–Go to Step 9Go to Step 11
91. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–
101. Replace the throttle body assembly.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–

1F – 170IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
111. Ignition OFF.
2. Replace the ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–Go to Step 12–
12Check 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 – 171
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0261
INJECTOR 1 LOW VOLTAGE
Circuit Description
The transaxle control module(TCM)/engine control mod-
ule (ECM) has four individual injector driver circuits, each
of which controls an injector. When a driver circuit is
grounded by the ECM, the injector is activated. The ECM
monitors the current in each driver circuit. The ECM mea-
sures a voltage drop through a fixed resistor and controls
it. The voltage on each driver is monitored to detect a fault.
If the voltage is not what the ECM expects to monitor on
the circuit, a Diagnostic Trouble Code (DTC) is set. This
DTC detects a low voltage and/or an open circuit and high
voltage conditions for low–side drive injector outputs.
Conditions for Setting the DTC
S The injector 1 circuit is an open or a short to ground
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 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 injector driver circuit that is open or shorted to voltage
will causes a DTC P0261 to set. It will also cause a misfire
due to an inoperative injector. A misfire DTC should also
be set indicating which injector is inoperative.
Long–term and short–terms fuel trims that are excessively
high or low are a good indication that an injector is mal-
functioning. Refer to ”Fuel Injector Balance Test” in this
section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is
slightly more than it tested directly at the injector because
it includes resistance of the harness wires. The normal val-
ue is about 13.5W.

1F – 172IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0261 – Injector 1 Low 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”
2Does the engine start?–Go to Step 3Go to
”Engine Cranks
But Will Not
Run”
31. Install a scan tool and clear the Diagnostic
Trouble Codes (DTCs).
2. Idle the engine for one minuet.
Does DTC P0261 reset?–Go to Step 5Go to Step 4
41. Review the Freeze Frame data with the ignition
ON and the engine OFF and note the parame-
ters.
2. Operate the vehicle within the Freeze Frame
conditions as notes.
Does DTC P0261 reset?–Go to Step 5Go to
”Diagnostic
Aids”
51. Turn the ignition switch to LOCK.
2. Check for short to ground in the wire between
the injector 1 connector terminal 2 and ECM
connector terminal 59.
Is the problem found?–Go to Step 7Go to Step 6
61. Turn the ignition switch to LOCK.
2. Check for short to ground in the wire between
the injector 1 connector terminal 1 and battery
positive.
Is the problem found?–Go to Step 7Go to Step 8
71. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–
81. Replace the injector valve.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–Go to Step 9System OK
91. Turn the ignition switch to LOCK.
2. Replace the ECM.
3. Perform the Diagnostic System Check.
Does DTC P0261 reset?–Go to Step 10–
10Check if any additional DTCs are set.
Are any DTCs displaced that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 173
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0262
INJECTOR 1 HIGH VOLTAGE
Circuit Description
The transaxle control module(TCM)/engine control mod-
ule (ECM) has four individual injector driver circuits, each
of which controls an injector. When a driver circuit is
grounded by the ECM, the injector is activated. The ECM
monitors the current in each driver circuit. The ECM mea-
sures a voltage drop through a fixed resistor and controls
it. The voltage on each driver is monitored to detect a fault.
If the voltage is not what the ECM expects to monitor on
the circuit, a Diagnostic Trouble Code (DTC) is set. This
DTC detects a low voltage and/or an open circuit and high
voltage conditions for low–side drive injector outputs.
Conditions for Setting the DTC
S The injector 1 circuit is a short to battery 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 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 injector driver circuit that is open or shorted to voltage
will causes a DTC P0262 to set. It will also cause a misfire
due to an inoperative injector. A misfire DTC should also
be set indicating which injector is inoperative.
Long–term and short–terms fuel trims that are excessively
high or low are a good indication that an injector is mal-
functioning. Refer to ”Fuel Injector Balance Test” in this
section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is
slightly more than it tested directly at the injector because
it includes resistance of the harness wires. The normal val-
ue is about 13.5W.

1F – 174IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0262 – Injector 1 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”
2Does the engine start?–Go to Step 3Go to ”Engine
Cranks But Will
Not Run”
31. Install a scan tool and clear the Diagnostic
Trouble Codes (DTCs).
2. Idle the engine for one minuet.
Does DTC P0262 reset?–Go to Step 5Go to Step 4
41. Review the Freeze Frame data with the ignition
ON and the engine OFF and note the parame-
ters.
2. Operate the vehicle within the Freeze Frame
conditions as notes.
Does DTC P0262 reset?–Go to Step 5Go to ”Diag-
nostic Aids”
51. Turn the ignition switch to LOCK.
2. Check for an open or short to battery voltage in
the wire between the injector 1 connector ter-
minal 2 and ECM connector terminal 59.
Is the problem found?–Go to Step 7Go to Step 6
61. Turn the ignition switch to LOCK.
2. Check for short to battery voltage in the wire
between the injector 1 connector terminal 1.
Is the problem found?–Go to Step 7Go to Step 8
71. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–
81. Replace the injector valve.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Does DTC P0262 reset?–Go to Step 9System OK
91. Turn the ignition switch to LOCK.
2. Replace the ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–Go to Step 10–
10Check if any additional DTCs are set.
Are any DTCs displaced that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 175
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0264
INJECTOR 2 LOW VOLTAGE
Circuit Description
The transaxle control module(TCM)/engine control mod-
ule (ECM) has four individual injector driver circuits, each
of which controls an injector. When a driver circuit is
grounded by the ECM, the injector is activated. The ECM
monitors the current in each driver circuit. The ECM mea-
sures a voltage drop through a fixed resistor and controls
it. The voltage on each driver is monitored to detect a fault.
If the voltage is not what the ECM expects to monitor on
the circuit, a Diagnostic Trouble Code (DTC) is set. This
DTC detects a low voltage and/or an open circuit and high
voltage conditions for low–side drive injector outputs.
Conditions for Setting the DTC
S The injector 2 circuit is an open or a short to ground
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 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 injector driver circuit that is open or shorted to voltage
will causes a DTC P0264 to set. It will also cause a misfire
due to an inoperative injector. A misfire DTC should also
be set indicating which injector is inoperative.
Long–term and short–terms fuel trims that are excessively
high or low are a good indication that an injector is mal-
functioning. Refer to ”Fuel Injector Balance Test” in this
section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is
slightly more than it tested directly at the injector because
it includes resistance of the harness wires. The normal val-
ue is about 13.5W.

1F – 176IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0264 – Injector 2 Low 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”
2Does the engine start?–Go to Step 3Go to
”Engine Cranks
But Will Not
Run”
31. Install a scan tool and clear the Diagnostic
Trouble Codes (DTCs).
2. Idle the engine for one minuet.
Does DTC P0264 reset?–Go to Step 5Go to Step 4
41. Review the Freeze Frame data with the ignition
ON and the engine OFF and note the parame-
ters.
2. Operate the vehicle within the Freeze Frame
conditions as notes.
Does DTC P0264 reset?–Go to Step 5Go to
”Diagnostic
Aids”
51. Turn the ignition switch to LOCK.
2. Check for short to ground in the wire between
the injector 2 connector terminal 2 and ECM
connector terminal 90.
Is the problem found?–Go to Step 7Go to Step 6
61. Turn the ignition switch to LOCK.
2. Check for short to ground in the wire between
the injector 2 connector terminal 1 and battery
positive.
Is the problem found?–Go to Step 7Go to Step 8
71. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–
81. Replace the injector valve.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Does DTC P0264 reset?–Go to Step 9System OK
91. Turn the ignition switch to LOCK.
2. Replace the ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–Go to Step 10–
10Check if any additional DTCs are set.
Are any DTCs displaced that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 177
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0265
INJECTOR 2 HIGH VOLTAGE
Circuit Description
The transaxle control module(TCM)/engine control mod-
ule (ECM) has four individual injector driver circuits, each
of which controls an injector. When a driver circuit is
grounded by the ECM, the injector is activated. The ECM
monitors the current in each driver circuit. The ECM mea-
sures a voltage drop through a fixed resistor and controls
it. The voltage on each driver is monitored to detect a fault.
If the voltage is not what the ECM expects to monitor on
the circuit, a Diagnostic Trouble Code (DTC) is set. This
DTC detects a low voltage and/or an open circuit and high
voltage conditions for low–side drive injector outputs.
Conditions for Setting the DTC
S The injector 2 circuit is a short to battery 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 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 injector driver circuit that is open or shorted to voltage
will causes a DTC P0265 to set. It will also cause a misfire
due to an inoperative injector. A misfire DTC should also
be set indicating which injector is inoperative.
Long–term and short–terms fuel trims that are excessively
high or low are a good indication that an injector is mal-
functioning. Refer to ”Fuel Injector Balance Test” in this
section to check for malfunctioning injectors.
The injector resistance tested at the ECM connection is
slightly more than it tested directly at the injector because
it includes resistance of the harness wires. The normal val-
ue is about 13.5W.

1F – 178IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0265 – Injector 2 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”
2Does the engine start?–Go to Step 3Go to
”Engine Cranks
But Will Not
Run”
31. Install a scan tool and clear the Diagnostic
Trouble Codes (DTCs).
2. Idle the engine for one minuet.
Does DTC P0265 reset?–Go to Step 5Go to Step 4
41. Review the Freeze Frame data with the ignition
ON and the engine OFF and note the parame-
ters.
2. Operate the vehicle within the Freeze Frame
conditions as notes.
Does DTC P0265 reset?–Go to Step 5Go to
”Diagnostic
Aids”
51. Turn the ignition switch to LOCK.
2. Check for an open or short to battery voltage in
the wire between the injector 2 connector ter-
minal 2 and ECM connector terminal 90.
Is the problem found?–Go to Step 7Go to Step 6
61. Turn the ignition switch to LOCK.
2. Check for high voltage in the wire between the
injector 2 connector terminal 1.
Is the problem found?–Go to Step 7Go to Step 8
71. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–System OK–
81. Replace the injector valve.
2. Clear any DTCs from ECM.
3. Perform the Diagnostic System Check.
Does DTC P0265 reset?–Go to Step 9System OK
91. Turn the ignition switch to LOCK.
2. Replace the ECM.
3. Perform the Diagnostic System Check.
Is the repair complete?–Go to Step 10–
10Check if any additional DTCs are set.
Are any DTCs displaced that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK