ENGINE CONTROLS 1F – 299
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1382
ROUGH ROAD DATA INVALID (NON ABS)
Circuit Description
The VR sensor is used to detecting the road situation.
By sensing difference of wheel rotation duration caused by
bumps or potholes in the road, the Engine Control Module
(ECM) can determine if the changes in crankshaft speed
are due to engine misfire or are driveline induced. If the VR
sensor detects a rough road condition, the ECM misfire
detection diagnostic will be de–activated.
Conditions for Setting the DTC
S Vehicle speed is higher than 5km/h(3.1mph).
S No Vehicle Speed Sensor error not set.
S VR sensor output signal is higher than 0.26.
S VR sensor output signal is not change for 30sec-
onds.Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
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.
ENGINE CONTROLS 1F – 301
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
9Check the VR sensor signal circuit for a poor con-
nection at the ECM and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 13
10Check for a poor connection at terminal 1 of the VR
sensor and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 11
11Replace the VR sensor.
Is the repair complete?–Go to Step 14–
121. Turn the ignition OFF.
2. Disconnect the ECM.
3. Turn the ignition ON.
4. Check the VR sensor signal circuit for a short
to battery voltage or a short to the 5 volt refer-
ence circuit and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 13
131. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 14–
141. 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 ran
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
1F – 302IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1382
ROUGH ROAD DATA INVALID (ABS)
Circuit Description
The wheel speed sensor is used to detecting the road situ-
ation.
As the wheel is rotated, the wheel speed sensor produces
an AC voltage that increase with wheel speed. The EBCM
uses the frequency of the AC signal to calculate wheel
speed. The wheel speed sensor is connected to EBCM by
a ”twisted pair” of wires. Twisting reduces noise suscepti-
bility than may cause a DTC to set. If the wheel speed sen-
sor detects a rough road condition, the ECM misfire detec-
tion diagnostic will be de–activated.
Conditions for Setting the DTC
S Vehicle speed is higher than 5km/h(3.1mph).
S No Vehicle Speed Sensor error not set.
S VR sensor output signal is higher than 0.26.S VR sensor output signal is not change for 30sec-
onds.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
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.
ENGINE CONTROLS 1F – 305
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1385
ROUGH ROAD SENSOR CIRCUIT FAULT (NON ABS)
Circuit Description
The VR sensor is used to detecting the road situation.
By sensing difference of wheel rotation duration caused by
bumps or potholes in the road, the Engine Control Module
(ECM) can determine if the changes in crankshaft speed
are due to engine misfire or are driveline induced. If the VR
sensor detects a rough road condition, the ECM misfire
detection diagnostic will be de–activated.
Conditions for Setting the DTC
S The VR sensor is greater than 0.06V.
Or
S The minimum value of the VR sensor is less than
1.5V.
OrS The maximum value of the VR sensor is greater
than 2.2V.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
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.
ENGINE CONTROLS 1F – 307
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
9Check the VR sensor signal circuit for a poor con-
nection at the ECM and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 13
10Check for a poor connection at terminal 1 of the VR
sensor and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 11
11Replace the VR sensor.
Is the repair complete?–Go to Step 14–
121. Turn the ignition OFF.
2. Disconnect the ECM.
3. Turn the ignition ON.
4. Check the VR sensor signal circuit for a short
to battery voltage or a short to the 5 volt refer-
ence circuit and repair as needed.
Is the repair complete?–Go to Step 14Go to Step 13
131. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 14–
141. 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 ran
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
ENGINE CONTROLS 1F – 309
DAEWOO V–121 BL4
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.
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 vehicle 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 P1402 – Exhaust Gas Recirculation Blocked
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. Start the engine and allow the engine to idle.
2. Install the scan tool.
3. Command the exhaust gas recirculation (EGR)
valve to the specified values.
Does the engine stall or attempt to stall?50%Go to Step 5Go to Step 3
31. Turn the ignition switch to LOCK.
2. Remove the EGR valve assembly.
3. Inspect the EGR valve, passages and pipe for
a restriction or damage and repair as neces-
sary.
Is a repair necessary?–Go to Step 5Go to Step 4
4Replace the EGR valve.
Is the replacement complete?–Go to Step 5–
51. Start the engine.
2. Disconnect the battery for the specified time.
3. Drive the vehicle to the specified value.
4. Release the throttle and allow the vehicle to
decelerate to the specified value.
Is the EGR Decel Filter Values less than the speci-
fied value?10 secnds
60mph
(27km/h)
20mph
(32km/h)
0mphGo to Step 3Go to Step 6
61. 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 7Go to Step 2
ENGINE CONTROLS 1F – 311
DAEWOO V–121 BL4
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.
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 vehicle 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 P1403 – Exhaust Gas Recirculation Valve Failure
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
1F – 312IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
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
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