2004 DAEWOO LACETTI jump cable

ENGINE CONTROLS 1F – 389
DAEWOO V–121 BL4
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 The 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 rubbed–through wire in-
sulation or a wire contacting the exhaust.
Check for the following conditions:
S Exhaust system – Inspect the exhaust system for
leaks. Check the exhaust between the three–way
catalytic converter and the flange for leaks, corro-
sion, or for loose or missing hardware and repair as
necessary.
S Poor connection or damaged harness – Ensure that
the HO2S2 pigtail is not contacting the exhaust.
Check for the following conditions:
S Improper mating
S Broken locks
S Improperly formedS Damaged terminals
S Poor terminal–to–wire connection
S Damaged harness
S Intermittent test – Observe the HO2S2 on the scan
tool while moving related connections and the wir-
ing harness with the ignition ON. If the failure is in-
duced, the HO2S2 display will change. This may
help isolate the location of the malfunction.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic 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. This step determines if DTC P0137 is the result of
a hard failure or an intermittent condition.
4. Jumping the HO2S2 low circuit, terminal 4 to
ground is necessary to allow the ECM to display
the supplied bias voltage. If the voltage is between
0.35 and 0.55 volt, then the wiring and ECM are
OK.
6. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
DTC P0137 – Rear Heated Oxygen Sensor (HO2S2) 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. Turn the ignition ON.
Is the Rear Heated Oxygen Sensor (HO2S2) volt-
age less than the value specified?0.1 VGo to Step 4Go to Step 3
31. Start the engine.
2. Review the Freeze Frame data and note the
parameters.
3. Operate the vehicle within the Freeze frame
conditions and Conditions For Setting the DTC
as noted.
Is the HO2S2 voltage less than the specified value?0.4 VGo to Step 4Go to Step 8
41. Turn the ignition OFF.
2. Disconnect HO2S2 connector.
3. Connect a jumper wire between terminal 1 of
HO2S2 connector and ground.
4. Turn the ignition ON.
Does the scan tool indicate that the HO2S2 voltage
is within the specified value?350–550 mVGo to Step 7Go to Step 5

1F – 392IENGINE CONTROLS
DAEWOO V–121 BL4
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 The DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
Check for the following conditions:
S Rich exhaust – An overly rich exhaust may load the
catalyst, causing high HO2S2 signal voltages.
S Silicone contamination – A false rich condition may
be caused by silicone contamination of the HO2S2.
This will be indicated by a powdery white deposit on
the sensor.
S Faulty HO2S2 – If HO2S2 is internally shorted, the
HO2S2 voltage displayed on a scan tool will be
over 1 volt. Disconnect the HO2S2 and jumper the
sensor low circuit to engine ground; if the displayed
voltage goes from over 1000 millivolt to around 450
millivolt, replace the HO2S2.S Intermittent test – Observe HO2S2 on the scan tool
while moving related connectors and the wiring har-
ness with the key in the ON position. If the failure is
induced, the HO2S2 display will change. This may
help isolate the location of the malfunction.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic 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. This step determines if DTC P0138 is the result of
a hard failure or an intermittent condition.
5. Disconnecting the HO2S2 and jumpering the sen-
sor signal circuit and the sensor low circuit to
ground should cause the scan tool to display
HO2S2 voltage below 100 mv (0.1 v). If the signal
voltage is still high, the ECM is malfunctioning.
6. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
DTC P0138 – Rear Heated Oxygen Sensor (HO2S2) 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. Turn the ignition ON.
Is the Rear Heated Oxygen Sensor (HO2S2) volt-
age above the value specified?0.9 VGo to Step 4Go to Step 3
31. Review the Freeze Frame data and note the
parameters.
2. Operate the vehicle within the Freeze frame
conditions and Conditions For Setting the DTC
as noted.
Is the HO2S2 voltage above the specified value?0.9 VGo to Step 4Go to Step 9
41. Turn the ignition OFF.
2. Disconnect HO2S2 connector.
3. Disconnect the Engine Control Module (ECM)
connector.
4. With voltmeter connected to ground, probe the
HO2S2 high signal circuit, terminal K36.
Is the voltage within the specified value?±0 VGo to Step 5Go to Step 6

ENGINE CONTROLS 1F – 393
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
51. Reconnect the ECM connector.
2. Turn the ignition ON.
3. Jumper the high and low circuits at the HO2S2
connector, terminals 1 and 2 to ground.
Does the scan tool indicate the HO2S2 voltage be-
low the specified value?0.1 VGo to Step 7Go to Step 8
6Repair the short to voltage in the HO2S2 high circuit.
Is the repair complete?–Go to Step 9–
7S Turn the ignition OFF.
S Replace the HO2S2.
Is the repair complete?–Go to Step 9–
8S Turn the ignition OFF.
S Replace the ECM.
Is the repair complete?–Go to Step 9–
91. 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 10Go to Step 2
10Check 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 – 395
DAEWOO V–121 BL4
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 The 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 rubbed–through wire
insulation or a wire contacting the exhaust.
Check for the following conditions:
S A poor connection or a damaged harness – Inspect
the harness for a short to ground in the sensor sig-
nal circuit. Ensure that the HO2S2 pigtail is not con-
tacting the exhaust. Check for the following condi-
tions:
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
S Damaged harness
S Intermittent test – Observe HO2S2 on the scan tool
while moving the related connections and the wiringharness with the ignition ON. If the failure is in-
duced, the HO2S2 display will change. This may
help isolate the location of the malfunction.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic 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. This step determines if DTC P0140 is the result of
a hard failure or an intermittent condition.
4. Disconnecting the HO2S2 and jumpering the sen-
sor signal circuit and the sensor low circuit to
ground will determine if the ECM or wiring or
HO2S2 is malfunctioning.
6. Determines which circuit the malfunction is in. If the
sensor signal circuit and the sensor low circuit are
OK, then the ECM connection or ECM is malfunc-
tioning.
10. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
DTC P0140 – Rear Heated Oxygen Sensor (HO2S2) No Activity or
Open
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 to normal operat-
ing temperature.
3. Run the engine above the specified rpm for two
minutes.
Does the scan tool display a Rear Heated Oxygen
Sensor (HO2S2) voltage between the value speci-
fied?80°C(176°F)
1200 rpm
422–478 mVGo to Step 4Go to Step 3
31. Allow the engine to idle.
2. Review the Freeze Frame data and note the
parameters.
3. Operate the vehicle within the Freeze frame
conditions and Conditions For Setting the DTC
as noted.
Does the scan tool display the HO2S2 voltage
steady around the value specified?422–478 mVGo to Step 11Go to Step 4

1F – 396IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
41. Turn the ignition OFF.
2. Disconnect HO2S2 connector.
3. Turn the ignition ON.
4. Jumper the high and low circuits at the HO2S2
connector, terminals 1 and 2 to ground.
Does the scan tool indicate the HO2S2 voltage be-
low the specified value?0.1 VGo to Step 5Go to Step 6
51. Turn the ignition OFF.
2. Check for a malfunctioning connection at the
HO2S2 Engine Control Module (ECM) side and
repair as needed.
Is the repair complete?–Go to Step 11Go to Step 7
61. Remove the jumper wire.
2. With a voltmeter connected to ground, probe
the terminal 2 of the HO2S2.
Does the voltage within the specified value?4.5 VGo to Step 8Go to Step 9
71. Turn the ignition OFF.
2. Replace the HO2S2.
Is the repair complete?–Go to Step 11–
8Check the HO2S2 low circuit for an open or poor
connection and repair as needed.
Is the repair complete?–Go to Step 11Go to Step 10
91. Turn the ignition OFF.
2. Disconnect the ECM connector.
3. Check the HO2S2 high circuit for continuity
and repair as needed.
Is the repair complete?–Go to Step 11Go to Step 5
101. Turn the ignition OFF.
2. Replace the HO2S2.
Is the repair complete?–Go to Step 11–
111. 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 12Go to Step 2
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 – 479
DAEWOO V–121 BL4
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic 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. Commanding the EGR valve open determines
whether the EGR system can control the EGR
valve accurately and if the fault is present.
3. If the EGR valve 5 volt reference is shorted to
ground, the digital voltmeter (DVM) will read no
voltage and additional DTCs may be set and the
engine performance will be poor. When this circuit
is open, only a DTC P0405 will be set.
4. Jumpering the 5 volt reference circuit to the signal
circuit checks the signal circuit and the ECM. The
scan tool should display the Actual EGR Position
as 100% if the signal circuit and ECM are OK.
6. Although the ECM and circuitry acted correctly in
the previous step, a problem may still lie within the
terminals which would not show up in probe typetesting. Be sure to check the terminals for being
backed out, improperly formed or damaged, and for
poor tension.
10. All circuits to the EGR valve are OK at this point.
The fault lies internally in the EGR valve and there-
fore must be replaced. Be sure all gasket material
is removed from the EGR mounting surface. Even
a small amount of material may cause a DTC
P0401 to set.
13. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
14. Check the terminals for being backed out, improp-
erly formed or damaged, and for poor tension.
15. Clearing DTCs is a very important step for this
diagnostic. The clearing function allows the EGR
valve to relearn a new pintle position as the old
pintle position was inaccurate due to the failure that
caused the DTC. The DTC must be cleared with
the ignition ON, engine OFF or when the engine is
idling. If the ECM sees an EGR command, the new
pintle will not be learned.
16. If no malfunctions have been found at this point and
no additional DTCs were set, refer to ”Diagnostic
Aids” in this section for additional checks and infor-
mation.
DTC P0405 – Exhaust Gas Recirculation Pintle Position 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. Turn the ignition ON.
3. Command the Exhaust Gas Recirculation
(EGR) valve to the specific values.
Does the Actual EGR Position follow the Desired
EGR Position?25%, 50%,
75%, 100%Go to Step 15Go to Step 3
31. Turn the ignition OFF.
2. Disconnect the EGR valve.
3. Turn the ignition ON.
4. With a voltmeter connected to the ground,
probe the 5 volt reference circuit at terminal 4
of the EGR valve wiring harness connector.
Is the voltage near the specified value?5 VGo to Step 4Go to Step 5
4Jumper the 5 volt reference circuit to the signal cir-
cuit at terminal 4 and C at the EGR valve wiring har-
ness connector.
Does the Actual EGR Position display the specific
value?100%Go to Step 6Go to Step 7

1F – 482IENGINE CONTROLS
DAEWOO V–121 BL4
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic 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. Commanding the EGR valve open determines
whether the EGR system can control the EGR
valve accurately and if the fault is present.
3. If the EGR valve 5 volt reference is shorted to
ground, the digital voltmeter (DVM) will read no
voltage and additional DTCs may be set and the
engine performance will be poor. When this circuit
is open, only a DTC P0405 will be set.
4. Jumpering the 5 volt reference circuit to the signal
circuit checks the signal circuit and the ECM. The
scan tool should display the Actual EGR Position
as 100% if the signal circuit and ECM are OK.
6. Although the ECM and circuitry acted correctly in
the previous step, a problem may still lie within the
terminals which would not show up in probe typetesting. Be sure to check the terminals for being
backed out, improperly formed or damaged, and for
poor tension.
10. All circuits to the EGR valve are OK at this point.
The fault lies internally in the EGR valve and, there-
fore, must be replaced. Be sure all gasket material
is removed from the EGR mounting surface. Even
a small amount of material may cause a DTC
P0401 to set.
12. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
13. Check the terminals for being backed out, improp-
erly formed or damaged, and for poor tension.
14. Clearing DTCs is a very important step for this
diagnostic. The clearing function allows the EGR
valve to relearn a new pintle position as the old
pintle position was inaccurate due to the failure that
caused the DTC. The DTC must be cleared with
the ignition ON, engine OFF or when the engine is
idling. If the ECM sees an EGR command, the new
pintle will not be learned.
15. no malfunctions have been found at this point and
no additional DTCs were set, refer to ”Diagnostic
Aids” in this section for additional checks and infor-
mation.
DTC P0406 – Exhaust Gas Recirculation Pintle Position 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. Install a scan tool to the Data Link Connector
(DLC).
3. Command the Exhaust Gas Recirculation
(EGR) valve to the specific 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 OFF.
2. Disconnect the EGR valve.
3. Turn the ignition ON.
4. With a voltmeter connected to the ground,
probe the 5 volt reference circuit at terminal 4
of the EGR valve wiring harness connector.
Is the voltage near the specified value?5 VGo to Step 4Go to Step 5
4Jumper the 5 volt reference circuit to the signal cir-
cuit at terminal 4 and C at the EGR valve wiring har-
ness connector.
Does the Actual EGR Position display the specific
value?100%Go to Step 6Go to Step 7

ENGINE CONTROLS 1F – 545
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
51. Turn the ignition OFF.
2. Disconnect the HO2S1 connector.
3. Turn the ignition ON.
4. Using a voltmeter, measure the voltage be-
tween following terminals.
5. Terminal 4 of Engine Control Module (ECM)
side HO2S1 connector and ground.
6. Terminal 3 of ECM side HO2S1 connector and
ground.
Are both voltages in the specified value?3–5 vGo to Step 6Go to Step 8
61. With the HO2S1 disconnected, jumper the
ECM side HO2S1 connector terminals 4 and 3.
2. Turn the ignition ON.
3. Using a scan tool, monitor the HO2S1 voltage.
Does the scan tool indicates less than 10 millivolts
and immediately return to about 450 millivolts when
the jumper is removed?–Go to Step 10Go to Step 9
7Repair conditions as needed.
Is the action complete?–Go to Step 14–
8Check for faulty ECM connections or terminal dam-
ages and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 9
9Repair open, short, or grounded signal circuit.
Is the repair complete?–Go to Step 14Step 11
10Remove the HO2S1 and examine it for sign of:
S Fuel contamination.
S Improper room temperature vulcanizing sealant
(white powdery coating on the sensor)
S Engine oil/coolant consumption.
Are sign of contamination observed?–Go to Step 12Go to Step 13
111. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 14Go to Step 13
12Determine and correct the cause of contamination.
Is the repair complete?–Go to Step 14
13Replace the HO2S1.
Is the repair complete?–Go to Step 14–
141. 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 15Go to Step 2
15Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK