Page 465 of 2643
ENGINE CONTROLS 1F – 219
DAEWOO V–121 BL4
S DTCs P0107, P0108, P0112, P0113, P0117,
P0118, P0122, P0123, P0131, P0300, P0335,
P0336, P0341, P0342, P1671, P1672, P1673 are
NOT SET.
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 Recordsbuffers.
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 P0400 – Exhaust Gas Recirculation Out of Limit
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 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 19Go to Step 3
31. Turn the ignition switch to ON.
2. Disconnect the EGR valve electrical connector.
3. With a test light connected to B+, probe the
ground circuit to the EGR valve.
Does the test light illuminate?–Go to Step 4Go to Step 5
41. Connect the test light to ground.
2. Probe the EGR control circuit at terminal 3 to
the EGR valve.
3. Command the EGR valve to the specified val-
ues using a scan tool.
After the command is raised, does the test light glow
brighter, flash or maintain a steady glow?25%, 50%
75%, 100%Go to Step 6Go to Step 7
5Repair the open or poor connection in the EGR
ground circuit.
Is the repair complete?–Go to Step 19–
6With a test light still connected to ground, probe the
signal circuit at terminal 3.
Does the test light illuminate?–Go to Step 8Go to Step 9
7With a test light still connected to ground, again
probe the signal circuit without commanding the
EGR valve with the scan tool.
Does the test light illuminate?–Go to Step 10Go to Step 11
8Check the signal circuit for a short to voltage and re-
pair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
9With a digital voltmeter (DVM) connected to ground,
probe the 5V reference circuit at terminal 1.
Is the voltage measured near the specified value?5VGo to Step 13Go to Step 14
Page 466 of 2643
1F – 220IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
10Check the control circuit for a short to battery voltage
and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
11Connect the test light to B+ and again probe the con-
trol circuit at terminal 4.
Does the test light illuminate?–Go to Step 15Go to Step 16
12Replace the engine control module (ECM).
Is the replacement complete?–Go to Step 19–
13Check the EGR ground circuit for a poor connection
or proper terminal tension at the ECM and repair as
necessary.
Is a repair necessary?–Go to Step 19Go to Step 17
14Check the 5V reference circuit for a shortage to bat-
tery voltage and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
15Check the control circuit for a shortage to ground
and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
16Check the control circuit for an open or poor connec-
tion at the EGR valve electrical connector and repair
as necessary.
Is a repair necessary?–Go to Step 19Go to Step 18
17Replace the EGR valve.
Is the replacement complete?–Go to Step 19–
18Check the ECM electrical connector for a poor con-
nection and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
191. 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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 20Go to Step 2
20Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK
Page 467 of 2643
ENGINE CONTROLS 1F – 221
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0404
EXHAUST GAS RECIRCULATION OPENED
Circuit Description
An Exhaust Gas Re–circulation (EGR) system is used to
lower oxides of nitrogen (NOx) emission levels caused by
high combustion temperatures. It accomplishes this by
feeding small amounts of exhaust gases back into the
combustion chamber. When the air/fuel mixture is diluted
with the exhaust gases, combustion temperatures are re-
duced.
A linear EGR valve is used on this system. The linear EGR
valve is designed to accurately supply exhaust gases to
the engine without the use of intake manifold vacuum. The
valve controls exhaust flow going into the intake manifold
from the exhaust manifold through an orifice with a engine
control module(ECM) controlled pintle. The ECM controls
the pintle position using inputs from the Throttle Position
(TP) and the Manifold Absolute Pressure (MAP) sensor.
The ECM then commands the EGR valve to operate when
necessary by controlling an ignition signal through the
ECM. This can be monitored on a scan tool as the Desired
EGR position.
The ECM monitors the results of its command through a
feedback signal. By sending a 5 volt reference and a
ground to the EGR valve, a voltage signal representing the
EGR valve pintle position is sent to the ECM. This feed-back signal can also be monitored on a scan tool and is the
actual position of the EGR pintle. The actual EGR position
should always be near the commanded or Desired EGR
position.
This Diagnostic Trouble Code(DTC) will detect an open or
short circuit.
Conditions for Setting the DTC
S EGR circuit is a short to ground or an open condi-
tion exist.
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.
Page 468 of 2643
1F – 222IENGINE CONTROLS
DAEWOO V–121 BL4
S Disconnecting the ECM battery feed for more than
10 seconds.
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 watching
the 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 P0404 – Exhaust Gas Recirculation Opened
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 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 19Go to Step 3
31. Turn the ignition switch to ON.
2. Disconnect the EGR valve electrical connector.
3. With a test light connected to B+, probe the
ground circuit to the EGR valve.
Does the test light illuminate?–Go to Step 4Go to Step 5
41. Connect the test light to ground.
2. Probe the EGR control circuit at terminal 3 to
the EGR valve.
3. Command the EGR valve to the specified val-
ues using a scan tool.
After the command is raised, does the test light glow
brighter, flash or maintain a steady glow?25%, 50%
75%, 100%Go to Step 6Go to Step 7
5Repair the open or poor connection in the EGR
ground circuit.
Is the repair complete?–Go to Step 19–
6With a test light still connected to ground, probe the
signal circuit at terminal 3.
Does the test light illuminate?–Go to Step 8Go to Step 9
7With a test light still connected to ground, again
probe the signal circuit without commanding the
EGR valve with the scan tool.
Does the test light illuminate?–Go to Step 10Go to Step 11
8Check the signal circuit for a short to voltage and re-
pair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
9With a digital voltmeter (DVM) connected to ground,
probe the 5V reference circuit at terminal 1.
Is the voltage measured near the specified value?5VGo to Step 13Go to Step 14
10Check the control circuit for a short to battery voltage
and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
11Connect the test light to B+ and again probe the con-
trol circuit at terminal 4.
Does the test light illuminate?–Go to Step 15Go to Step 16
Page 469 of 2643
ENGINE CONTROLS 1F – 223
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
12Replace the engine control module (ECM).
Is the replacement complete?–Go to Step 19–
13Check the EGR ground circuit for a poor connection
or proper terminal tension at the ECM and repair as
necessary.
Is a repair necessary?–Go to Step 19Go to Step 17
14Check the 5V reference circuit for a shortage to bat-
tery voltage and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
15Check the control circuit for a shortage to ground
and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
16Check the control circuit for an open or poor connec-
tion at the EGR valve electrical connector and repair
as necessary.
Is a repair necessary?–Go to Step 19Go to Step 18
17Replace the EGR valve.
Is the replacement complete?–Go to Step 19–
18Check the ECM electrical connector for a poor con-
nection and repair as necessary.
Is a repair necessary?–Go to Step 19Go to Step 12
191. 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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 20Go to Step 2
20Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK
Page 470 of 2643
1F – 224IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0405
EGR PINTLE POSITION SENSOR LOW VOLTAGE
Circuit Description
An Exhaust Gas Re–circulation (EGR) system is used to
lower oxides of nitrogen (NOx) emission levels caused by
high combustion temperatures. It accomplishes this by
feeding small amounts of exhaust gases back into the
combustion chamber. When the air/fuel mixture is diluted
with the exhaust gases, combustion temperatures are re-
duced.
A linear EGR valve is used on this system. The linear EGR
valve is designed to accurately supply exhaust gases to
the engine without the use of intake manifold vacuum. The
valve controls exhaust flow going into the intake manifold
from the exhaust manifold through an orifice with a engine
control module(ECM) controlled pintle. The ECM controls
the pintle position using inputs from the Throttle Position
(TP) and the Manifold Absolute Pressure (MAP) sensor.
The ECM then commands the EGR valve to operate when
necessary by controlling an ignition signal through the
ECM. This can be monitored on a scan tool as the Desired
EGR position.
The ECM monitors the results of its command through a
feedback signal. By sending a 5 volt reference and a
ground to the EGR valve, a voltage signal representing the
EGR valve pintle position is sent to the ECM. This feed-back signal can also be monitored on a scan tool and is the
actual position of the EGR pintle. The actual EGR position
should always be near the commanded or Desired EGR
position.
This Diagnostic Trouble Code(DTC) will detect an open or
short circuit.
Conditions for Setting the DTC
S EGR voltage is less than 0.01V.
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.
Page 471 of 2643
ENGINE CONTROLS 1F – 225
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 P0405 – EGR Pintle Position Sensor 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”
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 15Go 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 15Go to Step 10
71. Connect the test light to B+.
2. Probe the signal circuit at terminal 3 to the
EGR valve.
Does the test light illuminate?–Go to Step 11Go to Step 12
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 15Go to Step 13
9Check for an open in the EGR valve 5 volt reference
circuit and repair as necessary.
Is a repair necessary?–Go to Step 15Go to Step 14
10Replace the EGR valve.
Is the action complete?–Go to Step 15–
11Check for a short to ground in the EGR valve signal
circuit and repair as necessary.
Is a repair necessary?–Go to Step 15Go to Step 13
Page 472 of 2643
1F – 226IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
12Check for an open in the EGR valve signal circuit
and repair as necessary.
Is a repair necessary?–Go to Step 15Go to Step 14
131. Turn the ignition OFF.
2. Replace the Engine Control Module (ECM).
Is the action complete?–Go to Step 15–
14Check the affected circuit for a poor connection or
proper terminal at the ECM and repair as necessary.
Is a repair necessary?–Go to Step 15Go to Step 13
151. 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 the DTC as specified in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 16Go to Step 2
16Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK