mileage DAEWOO LACETTI 2004 Service Owner's Manual

1F – 522IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1106
MANIFOLD ABSOLUTE PRESSURE INTERMITTENT HIGH
VOLTAGE
Circuit Description
The Manifold Absolute Pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum). The
MAP signal voltage to the Engine Control Module (ECM)
varies from below 2 volts at idle (high vacuum) to above
4 volts with the key in the ON position, engine not running
or at Wide Open Throttle (WOT) (low vacuum).
A ”speed density” method of determining engine load is
used. This is calculated using inputs from the MAP sensor,
the rpm (58X), and the Intake Air Temperature (IAT) sen-
sor. The MAP sensor is the main sensor used in this cal-
culation, and measuring engine load is its main function.
The MAP sensor is also used to determine manifold pres-
sure changes while the linear Exhaust Gas Recirculation
(EGR) flow test diagnostic is being run (refer to DTC
P0401). This determines the engine vacuum level for
some other diagnostics and determines Barometric Pres-
sure (BARO). The ECM compares the MAP sensor signal
to calculated MAP based on Throttle Position (TP) and
various other engine load factors. If the ECM detects a
MAP signal voltage that is intermittently above the calcu-
lated value, DTC P1106 will set.
Conditions for Setting the DTC
S The MAP is greater than 103 kPa (15 psi).
S No TP sensor fail conditions present.
S Engine running more than 10 seconds
S TP sensor is less than 15 % if rpm is less than
2500.
S TP sensor less than 35% if rpm is greater than
2500.
Action Taken When the DTC SetsS 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.
Diagnostic Aids
Check for the following conditions:
S Leaking or plugged vacuum supply line to the MAP
sensor.
S Inspect ECM harness connectors for backed–out
terminals, improper mating, broken locks, improper-
ly formed or damaged terminals, and poor terminal–
towire connection.
S Inspect the wiring harness for damage. If the har-
ness appears to be OK, observe the MAP display
on the scan tool while moving connectors and wir-
ing harnesses related to the sensor. A change in
the display will indicate the location of the fault.
Reviewing the Fail Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

1F – 524IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1107
MANIFOLD ABSOLUTE PRESSURE INTERMITTENT LOW
VOLTAGE
Circuit Description
The Manifold Absolute Pressure (MAP) sensor responds
to changes in intake manifold pressure (vacuum). The
MAP signal voltage to the Engine Control Module (ECM)
varies from below 2 volts at idle (high vacuum) to above
4 volts with the key in the ON position, engine not running
or at Wide Open Throttle (WOT) (low vacuum).
A ”speed density” method of determining engine load is
used. This is calculated using inputs from the MAP sensor,
the rpm (58X), and the Intake Air Temperature (IAT) sen-
sor. The MAP sensor is the main sensor used in this cal-
culation, and measuring engine load is its main function.
The MAP sensor is also used to determine manifold pres-
sure changes while the linear Exhaust Gas Recirculation
(EGR) flow test diagnostic is being run (refer to DTC
P0401). This determines the engine vacuum level for
some other diagnostics and determines Barometric Pres-
sure (BARO). The ECM compares the MAP sensor signal
to calculated MAP based on Throttle Position (TP) and
various other engine load factors. If the ECM detects a
MAP signal voltage that is intermittently below the calcu-
lated value, DTC P1107 will set.
Conditions for Setting the DTC
S The MAP is less than 12 kPa (1.7 psi).
S No TP sensor fail conditions present.
S TP sensor is greater than 0% if rpm is less than
1000.
S TP sensor less than 5% if rpm is greater than 1000.
S System voltage is between 11–11.5 volts.
Action Taken When the DTC SetsS 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.
Diagnostic Aids
Check for the following conditions:
S Leaking or plugged vacuum supply line to the MAP
sensor.
S Inspect ECM harness connectors for backed–out
terminals, improper mating, broken locks, improper-
ly formed or damaged terminals, and poor terminal–
to–wire connection.
S Inspect the wiring harness for damage. If the har-
ness appears to be OK, observe the MAP display
on the scan tool while moving connectors and wir-
ing harnesses related to the sensor. A change in
the display will indicate the location of the fault.
Reviewing the Fail Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.

1F – 526IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1111
INTAKE AIR TEMPERATURE INTERMITTENT HIGH
VOLTAGE
Circuit Description
The Intake Air Temperature (IAT) sensor is a thermistor
which measures the temperature of the air entering the en-
gine. The Engine Control Module (ECM) applies 5 volts
through a pull–up resistor to the IAT sensor. When the in-
take air is cold, the resistance is high, and the ECM will
monitor a high signal voltage on the IAT signal circuit. If the
intake air is warm, the sensor resistance is lower causing
the ECM to monitor a lower voltage. Diagnostic Trouble
Code (DTC) P1111 will set when the ECM detects an inter-
mittent high signal voltage in the intake air temperature
sensor signal circuit or sensor.
Conditions for Setting the DTC
S IAT is less than –38°C (–36°F).
S DTCs P0502, P0117, P0118 are not set
S Engine has been running for over 120 seconds.
S Vehicles speed is less than 25 km/h (16 mph).
S Calculated air flow is less than 15 g/second.
S Engine Coolant Temperature (ECT) is above 70°C
(158°F).
Action Taken When the DTC Sets
S The ECM will substitute a default value for IAT.
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 The Malfunction Indicator Lamp (MIL) will not illumi-
nate.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 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 Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the IAT display on the scan tool while moving con-
nectors and wiring harnesses related to the IAT
sensor. A change in the IAT display will indicate the
location of the fault.
S Reviewing the Fail Records vehicle mileage since
the diagnostic test last failed may help determine
how often the condition that caused the DTC to be
set occurs. This may assist in diagnosing the condi-
tion.
S Use the Temperature vs. Resistance Values table
to evaluate the possibility of a skewed sensor. Re-
fer to ”Temperature vs. Resistance” in this section.

ENGINE CONTROLS 1F – 529
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1112
INTAKE AIR TEMPERATURE INTERMITTENT LOW
VOLTAGE
Circuit Description
The Intake Air Temperature (IAT) sensor is a thermistor
which measures the temperature of the air entering the en-
gine. The Engine Control Module (ECM) applies 5 volts
through a pull–up resistor to the IAT sensor. When the in-
take air is cold, the resistance is high, and the ECM will
monitor a high signal voltage on the IAT signal circuit. If the
intake air is warm, the sensor resistance is lower causing
the ECM to monitor a lower voltage. Diagnostic Trouble
Code (DTC) P1111 will set when the ECM detects an inter-
mittent high signal voltage in the intake air temperature
sensor signal circuit or sensor.
Conditions for Setting the DTC
S IAT is greater than 149°C (300°F).
S DTC P0502 is not set
S Engine has been running for over two minutes.
S Vehicles speed is greater than 50 km/h (31 mph).
Action Taken When the DTC Sets
S The ECM will substitute a default value for IAT.
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 The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
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 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 Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the IAT display on the scan tool while moving con-
nectors and wiring harnesses related to the IAT
sensor. A change in the IAT display will indicate the
location of the fault.
S Reviewing the Fail Records vehicle mileage since
the diagnostic test last failed may help determine
how often the condition that caused the DTC to be
set occurs. This may assist in diagnosing the condi-
tion.
S Use the Temperature vs. Resistance Values table
to evaluate the possibility of a skewed sensor. Re-
fer to ”Temperature vs. Resistance” in this section.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Chart.
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.

ENGINE CONTROLS 1F – 531
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1114
ENGINE COOLANT TEMPERATURE INTERMITTENT LOW
VOLTAGE
Circuit Description
The Engine Coolant Temperature sensor (ECT) is a
thermistor mounted in the engine coolant stream. The En-
gine control Module (ECM) applies 5 volt reference volt-
age through a pull–up resistor to the ECT signal circuit.
When the engine coolant is cold, the sensor resistance is
high, and the ECM will monitor a high signal voltage. As
the engine coolant warms, the sensor resistance is less,
and the ECT signal voltage measured at the ECM drops.
With a fully warmed engine, the ECT signal voltage should
measure about 1.5 to 2.0 volts. If the ECM detects an ECT
signal that is intermittently below the range of the ECT
sensor, Diagnostic Trouble Code (DTC) P1114 will set.
Conditions for Setting the DTC
S ECT is less than 149°C (300°F).
S Engine has been running for over 60 seconds.
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 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 Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the ECT display on the scan tool while moving con-
nectors and wiring harnesses related to the ECT
sensor. A change in the ECT display will indicate
the location of the fault.
S Reviewing the Fail Records vehicle mileage since
the diagnostic test last failed may help determine
how often the condition that caused the DTC to be
set occurs. This may assist in diagnosing the condi-
tion.
S Use the Temperature vs. Resistance Values table
to evaluate the possibility of a skewed sensor. Re-
fer to ”Temperature vs. Resistance” 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

ENGINE CONTROLS 1F – 533
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1115
ENGINE COOLANT TEMPERATURE INTERMITTENT HIGH
VOLTAGE
Circuit Description
The Engine Coolant Temperature sensor (ECT) is a
thermistor mounted in the engine coolant stream. The En-
gine control Module (ECM) applies 5 volt reference volt-
age through a pull–up resistor to the ECT signal circuit.
When the engine coolant is cold, the sensor resistance is
high, and the ECM will monitor a high signal voltage. As
the engine coolant warms, the sensor resistance is less,
and the ECT signal voltage measured at the ECM drops.
With a fully warmed engine, the ECT signal voltage should
measure about 1.5 to 2.0 volts. If the ECM detects an ECT
signal that is intermittently above the range of the ECT
sensor, Diagnostic Trouble Code (DTC) P1115 will set.
Conditions for Setting the DTC
S ECT is less than –38°C (–36°F).
S Engine has been running for over 90 seconds.
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 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 Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the ECT display on the scan tool while moving con-
nectors and wiring harnesses related to the ECT
sensor. A change in the ECT display will indicate
the location of the fault.
S Reviewing the Fail Records vehicle mileage since
the diagnostic test last failed may help determine
how often the condition that caused the DTC to be
set occurs. This may assist in diagnosing the condi-
tion.
S Use the Temperature vs. Resistance Values table
to evaluate the possibility of a skewed sensor. Re-
fer to ”Temperature vs. Resistance” 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.

ENGINE CONTROLS 1F – 535
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1121
THROTTLE POSITION SENSOR INTERMITTENT HIGH
VOLTAGE
Circuit Description
The Throttle Position (TP) sensor circuit provides a volt-
age signal that changes relative to throttle blade angle.
The TP sensor sends a voltage signal back to the Engine
Control Module (ECM) relative to the throttle plate open-
ing. The voltage signal will vary from approximately 0.33
volts at closed throttle, to over 4.3 volts at Wide Open
Throttle (WOT).
The TP signal is used by the ECM for fuel control and for
most of the ECM controlled outputs. The TP signal is one
of the most important inputs used by the ECM for fuel con-
trol and most of the ECM controlled outputs. If the ECM
detects a TP signal that is intermittently above the range
of the TP sensor, Diagnostic Trouble Code (DTC) P1121
will be set.
Conditions for Setting the DTC
S TP sensor voltage indicates a throttle voltage inter-
mittently greater than 4.9 volts.
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 will clear after 40 consecutive warm–up
cycles in which the diagnostic runs 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
Check for the following conditions:
S Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears OK, observe the
throttle position display on the scan tool while mov-
ing connectors and wiring harnesses related to the
TP sensor. A change in the display will indicate the
location of the fault.
If DTC P1121 cannot be duplicated, reviewing the Fail Re-
cords vehicle mileage since the diagnostic test last failed
may help determine how often the condition that caused
the DTC to be set occurs. This may assist in diagnosing
the condition.
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.

ENGINE CONTROLS 1F – 537
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1122
THROTTLE POSITION SENSOR INTERMITTENT LOW
VOLTAGE
Circuit Description
The Throttle Position (TP) sensor circuit provides a volt-
age signal that changes relative to throttle blade angle.
The TP sensor sends a voltage signal back to the Engine
Control Module (ECM) relative to the throttle plate open-
ing. The voltage signal will vary from approximately 0.33
volts at closed throttle, to over 4.3 volts at Wide Open
Throttle (WOT).
The TP signal is used by the ECM for fuel control and for
most of the ECM controlled outputs. The TP signal is one
of the most important inputs used by the ECM for fuel con-
trol and most of the ECM controlled outputs. If the ECM
detects a TP signal that is intermittently above the range
of the TP sensor, Diagnostic Trouble Code (DTC) P1122
will be set.
Conditions for Setting the DTC
S TP sensor voltage indicates a throttle voltage inter-
mittently less than 0.14 volts.
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 will clear after 40 consecutive warm–up
cycles in which the diagnostic runs 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
Check for the following conditions:
S Poor connection at the ECM. Inspect harness con-
nectors for backed–out terminals, improper mating,
broken locks, improperly formed or damaged termi-
nals, and poor terminal–to–wire connection.
S Damaged harness. Inspect the wiring harness for
damage. If the harness appears OK, observe the
throttle position display on the scan tool while mov-
ing connectors and wiring harnesses related to the
TP sensor. A change in the display will indicate the
location of the fault.
If DTC P1122 cannot be duplicated, reviewing the Fail Re-
cords vehicle mileage since the diagnostic test last failed
may help determine how often the condition that caused
the DTC to be set occurs. This may assist in diagnosing
the condition.
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.

1F – 544IENGINE CONTROLS
DAEWOO V–121 BL4
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
A malfunction in the HO2S1 ignition feed or ground circuit
may cause a DTC P1134 to set. Check HO2S1 circuitry for
intermittent faults or poor connections. If connections and
wiring are OK and DTC P1134 continues to set, replace
the HO2S1.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how open
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Chart.
3. A condition that affects pre–converter and post–
converter oxygen sensors indicates probable con-
tamination. To avoid damaging replacement sen-
sors, correct the condition which caused the
contamination before replacing the affected sen-
sors.
5. This step checks for conditions which may cause
the oxygen sensor to appear faulty. Correct any of
the described conditions if present.
8. To avoid damaging replacement sensors, correct
the condition which caused the contamination be-
fore replacing the affected sensors
DTC P1134 – Front Heated Oxygen Sensor (HO2S1) Transition
Ratio
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”
2Important : If any Diagnostic Trouble Codes (DTCs)
are set, refer to those DTCs before processing with
this diagnostic chart.
1. Install a scan tool to the Data Link Connector
(DLC).
2. Start the engine and idle at normal operating
temperature.
3. Operate the engine within parameters specified
under Conditions for Setting the DTC.
4. Using a scan tool, monitor specific DTC info for
DTC P1134 until the DTC P1134 test runs.
5. Note the test result.
Does the scan tool indicate DTC P1134 failed this
ignition?–Go to Step 3Go to
”Diagnostic
Aids”
3Perform an exhaust system leak test.
If an exhaust leak is found, repair as needed.
The exhaust leak isolated?–Go to Step 14Go to Step 4
4Visually/physically inspect for the following items:
S Front Heated Oxygen Sensor (HO2S1) is se-
curely installed.
S Corrosion on the terminals.
S Terminal tension.
S HO2S1 wiring harness for poor terminal con-
nection or damaged wiring.
Is a problem found in any of the above areas?–Go to Step 7Go to Step 5

1F – 552IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1391
G SENSOR ROUGH ROAD RATIONALITY
Circuit Description
TThe Gravity Sensing Rough Road (G) sensor is a vertical
low g–acceleration sensor. By sensing vertical accelera-
tion 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 G sensor detects a rough road condition,
the ECM misfire detection diagnostic will be de–activated.
The G sensor at rest output should be between 2.35–2.65
volts (+1G). During a rough road condition, the voltage
output can vary between 0.5 (–1G) and 4.5 volts (+3G).
Conditions for Setting the DTC
S Engine is running.
S Vehicle speed is less than or equal to 5 km/h (3.1
mph).
S G sensor output at idle indicates below –0.39 volts
or above 2.21 volts.
OR
S Engine is running more than 10 seconds and ve-
hicle speed is between 30 mph (50 km/h) and 70
mph (112 km/h).
S G sensor signal changes less than 0.00024 volts
while driving.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not 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
buffers.
S A history DTC is stored.Conditions for Clearing the MIL/DTC
S A history Diagnostic Trouble Code (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
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.
Since the G sensor shares the ECM 5 volt reference and
ground terminals with the A/C Pressure Sensor, a dam-
aged A/C Pressure Sensor harness or sensor could cause
a G sensor DTC to set. Refer to ”Multiple ECM Information
Sensor DTCs Set” in this section. in this section.
The G sensor will give correct voltages only if it is level and
mounted securely to its bracket.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the con