Page 417 of 2643
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.
Page 418 of 2643
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
Page 419 of 2643
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.
Page 420 of 2643
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
Page 421 of 2643
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.
Page 422 of 2643
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
Page 423 of 2643
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.
Page 424 of 2643
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