1F – 426IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0301
CYLINDER 1 MISFURE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is mis-
firing. The ECM looks for a quick drop in crankshaft speed.
This test is executed in blocks of 100 engine revolution
tests. It may take between one to several tests to store a
Diagnostic Trouble Code (DTC) and illuminate the Mal-
function Indicator Lamp (MIL). Under light misfire condi-
tions, it may also take more than one trip to set a DTC. Se-
vere misfire will flash the MIL, indicating that catalyst
damage is possible.
Conditions for Setting the DTC
S Emission threshold is 3%.
S 20 engine cycles have occurred since cranking has
started.
S A/C compressor clutch has not just engaged or dis-
engaged.
S Engine load and engine speed is in a detectable
region and is at or above zero torque.
S Camshaft Position (CMP) sensor is in synchroniza-
tion.
S Exhaust Gas Recirculation (EGR) flow diagnostic is
not in progress.
S Fuel level is greater than 12% of rated tank capac-
ity.
S Decel Fuel Cutoff (DFCO) not active.
S Throttle position change is less than 3% per 125
ms.
S Vehicle has not encountered an abusive engine
speed of 7000 rpm.
S Crankshaft speed patters are normal.
S Throttle position is less than 3% when vehicle
speed is greater than 10 km/h (6 mph).
S Vehicle voltage is between 11 and 16 volts.
S Engine Coolant Temperature (ECT) is between
–7°C (19°F) and 120°C (248°F).
S There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0336, P0337, P0341, P0342 and
P0502 are not set.
Action Taken When the DTC Sets
S The MIL will illuminate after two consecutive ignition
cycles in which the diagnostic runs with the fault
active.
Or
S The MIL will illuminate immediately and flash if mis-
fire is present.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
within the freeze frame conditions that the DTC
failed.
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 can also be the result of a defective reluctor
wheel. Remove the CKP sensor and inspect the reluctor
wheel through the sensor mount hole. Check for porosity
and the condition of wheel. If the DTC is intermittent refer
to ”Symptoms Diagnosis” in this section.
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.
3. A visual/physical inspection should include check-
ing the following components:
S The wiring for proper connections, pinches or
cuts.
S The ECM grounds for being clean and tight.
S The vacuum hoses for splits, kinks, and proper
connections as shown on the Vehicle Emission
Information label.
S Check thoroughly for any type of leak or restric-
tion.
S For air leaks at the throttle body mounting area
and intake manifold sealing surfaces.
5. When all the accumulators are relatively equal, then
the misfire is being caused by something that af-
fects the entire engine. When they are not then the
misfire is being caused by something that is specif-
ic to two or more cylinders.
6. Whenever the misfire is not present operating the
vehicle may be necessary to duplicate the condi-
tions in the Freeze Frame Data in order to detect
ENGINE CONTROLS 1F – 431
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0302
CYLINDER 2 MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is mis-
firing. The ECM looks for a quick drop in crankshaft speed.
This test is executed in blocks of 100 engine revolution
tests. It may take between one to several tests to store a
Diagnostic Trouble Code (DTC) and illuminate the Mal-
function Indicator Lamp (MIL). Under light misfire condi-
tions, it may also take more than one trip to set a DTC. Se-
vere misfire will flash the MIL, indicating that catalyst
damage is possible.
Conditions for Setting the DTC
S Emission threshold is 3%.
S 20 engine cycles have occurred since cranking has
started.
S A/C compressor clutch has not just engaged or dis-
engaged.
S Engine load and engine speed is in a detectable
region and is at or above zero torque.
S Camshaft Position (CMP) sensor is in synchroniza-
tion.
S Exhaust Gas Recirculation (EGR) flow diagnostic is
not in progress.
S Fuel level is greater than 12% of rated tank capac-
ity.
S Decel Fuel Cutoff (DFCO) not active.
S Throttle position change is less than 3% per 125
ms.
S Vehicle has not encountered an abusive engine
speed of 7000 rpm.
S Crankshaft speed patters are normal.
S Throttle position is less than 3% when vehicle
speed is greater than 10 km/h (6 mph).
S Vehicle voltage is between 11 and 16 volts.
S Engine Coolant Temperature (ECT) is between
–7°C (19°F) and 120°C (248°F).
S There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0336, P0337, P0341, P0342 and
P0502 are not set.
Action Taken When the DTC Sets
S The MIL will illuminate after two consecutive ignition
cycles in which the diagnostic runs with the fault
active.
Or
S The MIL will illuminate immediately and flash if mis-
fire is present.
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
within the freeze frame conditions that the DTC
failed.
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 can also be the result of a defective reluctor
wheel. Remove the CKP sensor and inspect the reluctor
wheel through the sensor mount hole. Check for porosity
and the condition of wheel. If the DTC is intermittent refer
to”Symptoms Diagnosis” in this section.
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.
3. A visual/physical inspection should include check-
ing the following components:
S The wiring for proper connections, pinches or
cuts.
S The ECM grounds for being clean and tight.
S The vacuum hoses for splits, kinks, and proper
connections as shown on the Vehicle Emission
Information label. Check thoroughly for any type
of leak or restriction.
S For air leaks at the throttle body mounting area
and intake manifold sealing surfaces.
5. When all the accumulators are relatively equal, then
the misfire is being caused by something that af-
fects the entire engine. When they are not then the
misfire is being caused by something that is specif-
ic to two or more cylinders.
6. Whenever the misfire is not present operating the
vehicle may be necessary to duplicate the condi-
tions in the Freeze Frame Data in order to detect
misfire. Depending on the engine load, the condi-
tions may have to be maintained for up to 20 sec-
onds. Whenever the misfire accumulators start to
increment, then misfire is present. A history misfire
counter will store the number of misfires that have
occurred until the DTC is cleared.
1F – 436IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0303
CYLINDER 3 MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is mis-
firing. The ECM looks for a quick drop in crankshaft speed.
This test is executed in blocks of 100 engine revolution
tests. It may take between one to several tests to store a
Diagnostic Trouble Code (DTC) and illuminate the Mal-
function Indicator Lamp (MIL). Under light misfire condi-
tions, it may also take more than one trip to set a DTC. Se-
vere misfire will flash the MIL, indicating that catalyst
damage is possible.
Conditions for Setting the DTC
S Emission threshold is 3%.
S 20 engine cycles have occurred since cranking has
started.
S A/C compressor clutch has not just engaged or dis-
engaged.
S Engine load and engine speed is in a detectable
region and is at or above zero torque.
S Camshaft Position (CMP) sensor is in synchroniza-
tion.
S Exhaust Gas Recirculation (EGR) flow diagnostic is
not in progress.
S Fuel level is greater than 12% of rated tank capac-
ity.
S Decel Fuel Cutoff (DFCO) not active.
S Throttle position change is less than 3% per 125
ms.
S Vehicle has not encountered an abusive engine
speed of 7000 rpm.
S Crankshaft speed patters are normal.
S Throttle position is less than 3% when vehicle
speed is greater than 10 km/h (6 mph).
S Vehicle voltage is between 11 and 16 volts.
S Engine Coolant Temperature (ECT) is between
–7°C (19°F) and 120°C (248°F).
S There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0336, P0337, P0341, P0342 and
P0502 are not set.
Action Taken When the DTC Sets
S The MIL will illuminate after two consecutive ignition
cycles in which the diagnostic runs with the fault
active.
Or
S The MIL will illuminate immediately and flash if mis-
fire is present.
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
within the freeze frame conditions that the DTC
failed.
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 can also be the result of a defective reluctor
wheel. Remove the CKP sensor and inspect the reluctor
wheel through the sensor mount hole. Check for porosity
and the condition of wheel. If the DTC is intermittent refer
to”Symptoms Diagnosis” in this section.
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.
3. A visual/physical inspection should include check-
ing the following components:
S The wiring for proper connections, pinches or
cuts.
S The ECM grounds for being clean and tight.
S The vacuum hoses for splits, kinks, and proper
connections as shown on the Vehicle Emission
Information label. Check thoroughly for any type
of leak or restriction.
S For air leaks at the throttle body mounting area
and intake manifold sealing surfaces.
5. When all the accumulators are relatively equal, then
the misfire is being caused by something that af-
fects the entire engine. When they are not then the
misfire is being caused by something that is specif-
ic to two or more cylinders.
6. Whenever the misfire is not present operating the
vehicle may be necessary to duplicate the condi-
tions in the Freeze Frame Data in order to detect
misfire. Depending on the engine load, the condi-
tions may have to be maintained for up to 20 sec-
onds. Whenever the misfire accumulators start to
increment, then misfire is present. A history misfire
counter will store the number of misfires that have
occurred until the DTC is cleared.
ENGINE CONTROLS 1F – 441
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0304
CYLINDER 4 MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is mis-
firing. The ECM looks for a quick drop in crankshaft speed.
This test is executed in blocks of 100 engine revolution
tests. It may take between one to several tests to store a
Diagnostic Trouble Code (DTC) and illuminate the Mal-
function Indicator Lamp (MIL). Under light misfire condi-
tions, it may also take more than one trip to set a DTC. Se-
vere misfire will flash the MIL, indicating that catalyst
damage is possible.
Conditions for Setting the DTC
S Emission threshold is 3%.
S 20 engine cycles have occurred since cranking has
started.
S A/C compressor clutch has not just engaged or dis-
engaged.
S Engine load and engine speed is in a detectable
region and is at or above zero torque.
S Camshaft Position (CMP) sensor is in synchroniza-
tion.
S Exhaust Gas Recirculation (EGR) flow diagnostic is
not in progress.
S Fuel level is greater than 12% of rated tank capac-
ity.
S Decel Fuel Cutoff (DFCO) not active.
S Throttle position change is less than 3% per 125
ms.
S Vehicle has not encountered an abusive engine
speed of 7000 rpm.
S Crankshaft speed patters are normal.
S Throttle position is less than 3% when vehicle
speed is greater than 10 km/h (6 mph).
S Vehicle voltage is between 11 and 16 volts.
S Engine Coolant Temperature (ECT) is between
–7°C (19°F) and 120°C (248°F).
S There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0336, P0337, P0341, P0342 and
P0502 are not set.
Action Taken When the DTC Sets
S The MIL will illuminate after two consecutive ignition
cycles in which the diagnostic runs with the fault
active.
Or
S The MIL will illuminate immediately and flash if mis-
fire is present.
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
within the freeze frame conditions that the DTC
failed.
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 can also be the result of a defective reluctor
wheel. Remove the CKP sensor and inspect the reluctor
wheel through the sensor mount hole. Check for porosity
and the condition of wheel. If the DTC is intermittent refer
to”Symptoms Diagnosis” in this section.
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.
3. A visual/physical inspection should include check-
ing the following components:
S The wiring for proper connections, pinches or
cuts.
S The ECM grounds for being clean and tight.
S The vacuum hoses for splits, kinks, and proper
connections as shown on the Vehicle Emission
Information label. Check thoroughly for any type
of leak or restriction.
S For air leaks at the throttle body mounting area
and intake manifold sealing surfaces.
5. When all the accumulators are relatively equal, then
the misfire is being caused by something that af-
fects the entire engine. When they are not then the
misfire is being caused by something that is specif-
ic to two or more cylinders.
6. Whenever the misfire is not present operating the
vehicle may be necessary to duplicate the condi-
tions in the Freeze Frame Data in order to detect
misfire. Depending on the engine load, the condi-
tions may have to be maintained for up to 20 sec-
onds. Whenever the misfire accumulators start to
increment, then misfire is present. A history misfire
counter will store the number of misfires that have
occurred until the DTC is cleared.
ENGINE CONTROLS 1F – 445
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0317
ROUGH ROAD SENSOR SOURCE NOT DETECTED
System Description
The Engine Control Module (ECM) identifies engine mis-
fire by detecting variations in crankshaft speed. Crank-
shaft speed variations can also occur when a vehicle is op-
erating over a rough road. The ECM receives rough road
signal by gravity sensing rough road (G) sensor or Elec-
tronic Brake Control Module (EBCM) if equipped with the
Anti–Lock Brake System (ABS). The ABS can detect if the
vehicle is on the rough surface based on wheel accelera-
tion/deceleration data supplied by each wheel speed sen-
sor. This information sent to the ECM by EBCM through
serial data line. The G sensor is vertical low g–accelera-
tion sensor. By sensing vertical acceleration caused by
bumps or portholes in the road, the ECM determine if the
changes in crankshaft speed are due to engine misfire or
are driveline induced. If the ECM can not receive any of
those signal, a historic Diagnostic Trouble Code (DTC) will
be stored.
Conditions for Setting the DTCS ECM can not detect any rough road source.
S Vehicle speed is greater than 5km/h (3.1 mph).
Action Taken When the DTC Sets
S The MIL will not illuminate.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
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 open signal circuit of G sensor or open serial data line
between the ECM and the EBCM will be the cause of this
DTC.
1F – 550IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1336
58X CRANK POSITION TOOTH ERROR NOT LEARNED
Circuit Description
In order to detect engine misfire at higher engine speeds,
the Engine Control Module (ECM) must know of any varia-
tion between the crankshaft sensor pulses. Most varia-
tions are due to the machining of the crankshaft reluctor
wheel. However, other sources of variation are also pos-
sible. A Crankshaft Position (CKP) system variation learn-
ing procedure must be performed any time a change is
made to the crankshaft sensor to crankshaft relationship
of if the ECM is replaced or reprogrammed. The ECM
measures the variations and then calculates compensa-
tion factors needed to enable the ECM to accurately de-
tect engine misfire at all speeds and loads. A scan tool
must be used to command the ECM to learn these varia-
tions. If for any reason the ECM is unable to learn these
variations or they are out of an acceptable range, the ECM
will set Diagnostic Trouble Code (DTC) P1336. An ECM
that has not had the CKP system variation learning proce-
dure performed due to replacement or reprogramming will
also set DTC P1336.
Conditions for Setting the DTC
S Tooth error not learned if the manufacture enable
counter is set to zero.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0132, P0201, P0202, P0203,
P0204, P0325 , 0327, P0336, P0337, P0341,
P0342, P0351, P0352, P0402, P1404, P0404,
P0405, P0406 and P0502 are not set.
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 Failure Records
buffer.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn OFF after four consecutive igni-
tion 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 Disconnecting the ECM battery feed for more than
10 seconds.
S DTC(s) can be cleared by using the scan tool.Diagnostic Aids
CAUTION : To avoid personal injury when performing
the crankshaft position system variation learning
procedure, always set the vehice parking brake and
block the drive wheels. Release the throttle immedi-
ately when the engine starts to decelerate. Once the
learn procedure is completed, engine control will be
returned to the operator, and the engine will respond
to throttle position.
DTC P1336 will only set if the ECM has not learned the
CKP system variation. The ECM only needs to learn this
variation once per life cycle of the vehicle unless the crank
sensor to crankshaft relationship is disturbed. Removing
a part is considered a disturbance. A fully warmed engine
is critical to learning the variation correctly. If a valid learn
occurs, no other learns can be completed that ignition
cycle.
If the engine cuts out before the specified learn procedure
engine speed or at normal fuel cutoff rpm, the ECM is not
in the learn procedure mode.
Test Description
The number(s) below refer to step(s) on the diagnostic
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 fault occurred. The information is then stored on
the scan tool for later reference.
2. Engine temperature is critical to properly learn the
CKP system variation. Failure to properly warm the
engine before performing this procedure will result
in an inaccurate measurement of the CKP system
variation. The ECM learns this variation as the en-
gine is decelerating and then allows engine control
to be returned to the operator. All accessories must
be OFF when learning the CKP system angle varia-
tion. If the A/C is not disabled when the learn pro-
cedure is enabled, the ECM will disable the A/C.
3. If after the specified number attempts the ECM
cannot learn the CKP system variation, then the
variation is too large and no further attempts should
be made until the variation problem is corrected.
4. Being unable to learn the procedure indicates that
the variation is out of range.
5. After the CKP system variation has been learned,
wait above 10 seconds with ignition switch OFF to
prevent being cleared the learned value.
ENGINE CONTROLS 1F – 561
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1396
ABS WSS SIGNAL VARIATION
Circuit Description
The Engine Control Module (ECM) determines linear
wheel speed excessive variation. The wheel speed varia-
tion test detects at least one missing edge from the wheel
speed sensor signal.
Conditions for Setting the DTC
S WSS variation is greater than 18km/h (11.2 mph).
S Vehicle speed is greater than 10km/h (6.2 mph).
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 set as Failure Records data only.
This information will not be stored as Freeze Frame
data.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
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.
Diagnostic Aids
Check for the following conditions:S Poor connection at the ECM – Inspect the harness
connections for backed–out terminals, improper
mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connec-
tion.
S Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the G sensor display on the scan tool while moving
connectors and wiring harnesses related to the sen-
sor. A change in the display will indicate the loca-
tion of the fault.
An open signal circuit of open PWM serial data line be-
tween the ECM and the EBCM will be the cause of this
DTC.
Test Description
The number(s) below refer to specific step(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.
6. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
ENGINE CONTROLS 1F – 563
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1397
ABS WSS NO SIGNAL
Circuit Description
The Engine Control Module (ECM) determines linear
wheel speed fail threshold. The ECM detects a good or
failed wheel speed sensor under power conditions.
Conditions for Setting the DTC
S Vehicle speed is greater than 10km/h (6.2 mph).
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 set as Failure Records data only.
This information will not be stored as Freeze Frame
data.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
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.
Diagnostic Aids
Check for the following conditions:S Poor connection at the ECM – Inspect the harness
connections for backed–out terminals, improper
mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connec-
tion.
S Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the G sensor display on the scan tool while moving
connectors and wiring harnesses related to the sen-
sor. A change in the display will indicate the loca-
tion of the fault.
An open signal circuit of open PWM serial data line be-
tween the ECM and the EBCM will be the cause of this
DTC.
Test Description
The number(s) below refer to specific step(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.
6. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.