engine coolant DAEWOO MATIZ 2003 Service Service Manual
[x] Cancel search | Manufacturer: DAEWOO, Model Year: 2003, Model line: MATIZ, Model: DAEWOO MATIZ 2003Pages: 1184, PDF Size: 36 MB
Page 173 of 1184
ENGINE CONTROLS 1F–75
DAEWOO M-150 BL2
DTC P0118 – Engine Coolant Temperature Sensor High Voltage
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the system check complete?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Connect the scan tool to the data link connector
(DLC).
2. Run the engine until it reaches operating
temperature.
Does the scan tool show the ECT sensor reading
within the value specified?
80~110°C
(176~230°F)
Go to
“Diagnostic
Aids”
Go to Step 3
3
1. Turn the ignition switch to LOCK.
2. Disconnect the ECT sensor connector.
3. Turn the ignition switch to ON.
Does the scan tool show the ECT sensor reading
within the value specified?
≥-30°CGo to Step 4Go to Step 6
4
1. Jumper the ECT sensor signal circuits at terminal
B and A.
2. Turn the ignition switch to ON.
Does the scan tool show the ECT sensor reading
within the value specified?
≥180°C
(356°F)
Go to Step 5Go to Step 6
5
1. Replace the ECT sensor.
2. Clear any DTCs from the ECM.
3. Perform the diagnostic system check.
Is the replacement complete?
–
System OK
–
6
Measure the voltage between ECT terminal B and
ground.
Does the voltage measure within the value
specified?
4.5–5.0VGo to Step 7Go to Step 8
7
1. Turn the ignition switch to LOCK.
2. Disconnect the ECM wiring connector.
3. Check for a faulty connector or terminals at the
ECT sensor connector terminal A and the ECM
connector terminal 45 for an open or short to
battery voltage.
Is the problem found?
–
Go to Step 8Go to Step 9
8
1. Turn the ignition switch to LOCK.
2. Repair the wire of the connector terminals as
needed.
3. Clear any DTCs from the ECM.
4. Run the engine until it reaches operating
temperature.
5. Perform the diagnostic system check.
Is the repair complete?
–
System OK
–
9
1. Replace the ECM.
2. Run the engine until it reaches operating
temperature.
3. Perform the diagnostic system check.
Is the repair complete?
–
Go to Step 10
–
10
Check if any additional DTCs are set.
Are any DTCs displaced that have not been
diagnosed?
–
Go to
applicable DTC
table
System OK
Page 188 of 1184
1F–90 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F130
DIAGNOSTIC TROUBLE CODE (DTC) – P0133 OXYGEN SENSOR NO ACTIVITY
Circuit Description
The engine control module (ECM) supplies a voltage of
about 450mm volts between the ECM terminals 44 and
13. The oxygen (O
2) sensor varies the voltage within a
range of about 1volt if the exhaust is rich, down to about
100mm volts if the exhaust is lean. The O
2 sensor is like
an open circuit and produces no voltage when it is below
360°C(600°F). An open O
2 sensor circuit or a cold O2
sensor causes “open loop” operation.
Conditions for Setting the DTC
The engine controls system is in closed loop.
Engine Coolant Temperature is higher than 60°C
(140°F).
The mass air flow(MAF) is between 75mg/tdc and
100mg/tdc.
The engine speed is between 3,008rpm and
3,500rpm.
The vehicle speed is between 45km/h(27.96mph)
and 55km/h(34.2mph).
The manifold air pressure is higher than 90kPa.
The ignition is at 10 volts.
The upstream O
2 sensor periods higher than 1.6 sec-
onds.
A number of glitches higher than 5 during the test.DTCs P0107, P0108, P0112, P0113, P0117, P0118,
P0122, P0123, P0131, P0132, P0131, P0132,
P0137, P0138, P1671, P0300, P0335, P0336,
P0341, P0400, P0404, P0405, P0444, P0445 are
NOT SET.
Action Taken when the DTC Sets
Emission related.
“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Normal scan tool voltage varies between 0.15 to 8.5mV
while in Closed Loop. If DTC P0133 is intermittent, refer
to “Intermittent” in this Section.
Page 198 of 1184
1F–100 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F140
DIAGNOSTIC TROUBLE CODE (DTC) – P0140 HEATED OXYGEN SENSOR NO
ACTIVITY
Circuit Description
The engine control module (ECM) supplies a voltage of
about 450mm volts between the ECM terminals 64 and
13. The oxygen (O
2) sensor varies the voltage within a
range of about 1volt if the exhaust is rich, down to about
100mm volts if the exhaust is lean. The O
2 sensor is like
an open circuit and produces no voltage when it is below
360°C(600°F). An open O
2 sensor circuit or a cold O2
sensor causes “open loop” operation.
Conditions for Setting the DTC
The engine controls system is in closed loop.
Engine Coolant Temperature is higher than 70°C
(140°F).
The mass air flow(MAF) is between 25kg/h and
50kg/h.
The engine speed is between 2,400rpm and 300rpm.
The vehicle speed is between 64km/h(12.4mph) and
80km/h(24.9mph).
The manifold air pressure is higher than 70kPa.
The ignition is at 10 volts.
No transition from rich side to lean side or lean side to
rich side during 7.8 seconds even with a forcing of O
2
sensor controller.
DTCs P0107, P0108, P0112, P0113, P0117, P0118,
P0122, P0123, P0137, P0138, P0137, P0138,P0137, P0138, P1671, P0300, P0335, P0336,
P0341, P0400, P0404, P0405, P0644, P0645 are
NOT SET.
Action Taken when the DTC Sets
Emission related.
“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
Normal scan tool voltage varies between 0.15 to
8.5mV while in Closed Loop. If DTC P0140 is inter-
mittent, refer to “Intermittent” in this Section.
Page 204 of 1184
1F–106 ENGINE CONTROLS
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0171 FUEL TRIM SYSTEM TOO LEAN
System Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a Closed Loop air/
fuel metering system is used. While in Closed Loop, the
Engine Control Module (ECM) monitors the oxygen sen-
sor (O2S) signal voltage and adjusts fuel delivery based
on signal voltage. A change made to fuel delivery will be
indicated by the long and short term fuel trim values
which can be monitored with the scan tool. Ideal fuel trim
values are around 128 (0%). If the O2S signal is indicat-
ing a lean condition, the ECM will add fuel resulting in
fuel trim values above 128 (0% to 100%). If a rich condi-
tion is detected, the fuel trim values will be below 128
(0% to –100%), indicating that the ECM is reducing the
amount of fuel delivered. If exhaust emissions reach an
excessive level due to a lean or rich condition, a fuel trim
Diagnostic Trouble Code (DTC) is set.
Conditions for Setting the DTC
No intrusive tests active.
DTCs P0106, P0107, P0108, P0112, P0113, P0117,
P0118, P0122, P0123, P0125, P0131, P0132,
P0133, P0134, P0137, P0138, P0140, P0141,
P1167, P1171, P0201, P0202, P0203, P0204,
P0300, P0336, P0337, P0341, P0342, P0402,
P0404, P1404, P0405, P0406, P0443, P0506, and
P0507are not set.
The average of short term fuel trim value is greater
than or equal to 120.
Throttle Position (TP) is less than 95%.
Engine speed is between 700 and 6000 rpm.
Barometric Pressure (BARO) is greater than 92.0
kPa (10.4 psi).
Coolant temperature is between 80°C (176°F) and
11 5°C (239°F).
Manifold Absolute Pressure (MAP) is more than 90
kPa (10.2 psi).
System is in closed loop.
Adaptive index is ready.
Action Taken when the DTC Sets
Emission related.
“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Important: After repairs, use the scan tool Fuel Trim
Reset function to reset the long-term fuel trim to 128
(0%).
Fuel pressure – The system will be lean if the pres-
sure is too low. It may be necessary to monitor fuel
pressure while driving the vehicle at various road
speeds and/or loads to confirm.
Map sensor – An output that causes the ECM to
sense a lower than normal manifold pressure (high
vacuum) can cause the system to go lean. Discon-
necting the MAP sensor will allow the ECM to substi-
tute a fixed (default) value for the MAP sensor. If the
lean condition is gone when the sensor is discon-
nected, substitute a known good sensor and recheck.
Fuel contamination – Water, in even small amounts,
near the in-tank fuel pump inlet can be delivered to
the injector. The water causes a lean exhaust and
can set DTC P0171.
Check for poor O2S or MAP sensor connection at the
ECM. Inspect the harness connectors for the following
conditions:
Backed-out terminals
Improper mating
Broken locks
Improperly formed
Damaged terminals
Poor terminal-to-wire connection
Inspect the wiring harness for damage. If the harness
appears to be OK, observe the O2S display on the scan
tool while moving the connectors and the wiring harness
related to the engine harness. A change in the display
will indicate the location of the fault.
Check the brake power booster check valve for possible
leaks.
Page 207 of 1184
ENGINE CONTROLS 1F–109
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0172 FUEL TRIM SYSTEM TOO RICH
System Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a Closed Loop air/
fuel metering system is used. While in Closed Loop, the
Engine Control Module (ECM) monitors the oxygen sen-
sor (O2S) signal voltage and adjusts fuel delivery based
on signal voltage. A change made to fuel delivery will be
indicated by the long and short term fuel trim values
which can be monitored with the scan tool. Ideal fuel trim
values are around 128 (0%). If the O2S signal is indicat-
ing a lean condition, the ECM will add fuel resulting in
fuel trim values above 128 (0% to 100%). If a rich condi-
tion is detected, the fuel trim values will be below 128
(0% to –100%), indicating that the ECM is reducing the
amount of fuel delivered. If exhaust emissions reach an
excessive level due to a lean or rich condition, a fuel trim
Diagnostic Trouble Code (DTC) is set.
Conditions for Setting the DTC
No intrusive tests active.
DTCs P0106, P0107, P0108, P0112, P0113, P0117,
P0118, P0122, P0123, P0131, P0132, P0133,
P0134, P0137, P0138, P1167, P1171, P0300,
P0336, P0337, P0341, P0342, P0402, P0404,
P1404, P0405, P0406, P0443, P0506, and P0507are
not set.
The average of short term fuel trim value is greater
than or equal to 120.
Throttle Position (TP) is less than 95%.
Engine speed is between 700 and 6000 rpm.
Barometric Pressure (BARO) is greater than 90.0
kPa (10.4 psi).
Coolant temperature is between 80°C (176°F) and
11 5°C (239°F).
Manifold Absolute Pressure (MAP) is more than 70
kPa (10.2 psi).
System is in closed loop.
Adaptive index is ready.
Action Taken when the DTC Sets
Emission related.“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Important: After repairs, use the scan tool Fuel Trim
Reset function to reset the long-term fuel trim to 128
(0%).
Check for poor connection at the ECM. Inspect the har-
ness connectors for the following conditions:
Backed-out terminals.
Improper mating.
Broken locks.
Improperly formed.
Damaged terminals.
Poor terminal-to-wire connection.
Inspect the wiring harness for damage. If the harness
appears to be OK, observe the O2S display on the scan
tool while moving the connectors and the wiring harness
related to the engine harness. A change in the display
will indicate the location of the fault.
If a DTC P1404 is also set, check the 5 volt reference
circuits for a short to voltage.
Check for a restricted exhaust system.
A shorted 5 volt reference circuit may cause a DTC
P0172 to set. Check the 5 volt reference sensors for ab-
normal readings.
Page 212 of 1184
1F–114 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F040
DIAGNOSTIC TROUBLE CODE (DTC) – P1230 FUEL PUMP RELAY LOW
V O LTA G E
Circuit Description
When the ignition switch is turned ON, the ECM will acti-
vate the fuel pump relay and run the in-tank fuel pump.
The fuel pump will operate as long as the engine is
cranking or running and the ECM is receiving ignition
reference pulses.
Conditions for Setting the DTC
This DTC can be stored in “key-on” status.
An open or low voltage condition exists.
Action Taken when the DTC Sets
The Malfunction Indicator Lamp (MIL) will illuminate.
The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored in
the Freeze Frame and Records buffers.
A history DTC is stored.
Coolant fan turns ON.
Conditions for Clearing the MIL/DTC
The MIL will turn off after 4 consecutive ignition
cycles in which the diagnostic runs without a fault.A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An Intermittent problem may be caused by a poor con-
nection, rubbed through wire insulation, or wire that is
broken inside the insulation.
Any circuitry, that is suspected as causing the com-
plaint, should be thoroughly checked for the following
conditions.
Backed-out terminals
Improper mating
Broken locks
Improperly formed
Damaged terminals
Poor terminals to wire connection
Physical damage to the wiring harness
Page 216 of 1184
1F–118 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F040
DIAGNOSTIC TROUBLE CODE (DTC) – P1231 FUEL PUMP RELAY HIGH
V O LTA G E
Circuit Description
When the ignition switch is turned ON, the ECM will acti-
vate the fuel pump relay and run the in-tank fuel pump.
The fuel pump will operate as long as the engine is
cranking or running and the ECM is receiving ignition
reference pulses.
Conditions for Setting the DTC
This DTC can be stored in “key-on” status.
A high voltage condition exists.
Action Taken when the DTC Sets
The Malfunction Indicator Lamp (MIL) will illuminate.
The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored in
the Freeze Frame and Records buffers.
A history DTC is stored.
Coolant fan turns ON.
Conditions for Clearing the MIL/DTC
The MIL will turn off after 4 consecutive ignition
cycles in which the diagnostic runs without a fault.A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An Intermittent problem may be caused by a poor con-
nection, rubbed through wire insulation, or wire that is
broken inside the insulation.
Any circuitry, that is suspected as causing the com-
plaint, should be thoroughly checked for the following
conditions.
Backed-out terminals
Improper mating
Broken locks
Improperly formed
Damaged terminals
Poor terminals to wire connection
Physical damage to the wiring harness
Page 233 of 1184
ENGINE CONTROLS 1F–135
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0300 MULTIPLE CYLINDER MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is
misfiring. The ECM looks for a quick drop in crankshaft
speed. This test is executed in blocks of 100 engine rev-
olution tests. It may take between one to several tests to
store a Diagnostic Trouble Code (DTC) and illuminate
the Malfunction Indicator Lamp (MIL). Under light misfire
conditions, it may also take more than one trip to set a
DTC. Severe misfire will flash the MIL, indicating that
catalyst damage is possible.
Conditions for Setting the DTC
Emission threshold is 3.0% for manual transaxle.
20 engine cycles have occurred since cranking has
started.
A/C compressor clutch has not just engaged or disen-
gaged.
Engine load and engine speed are in a detectable re-
gion and are at or above zero torque.
Camshaft Position (CMP) sensor is in synchroniza-
tion.
Electric Exhaust Gas Recirculation (EEGR) flow
diagnostic is not in progress.
Fuel level is greater than or equal to 20% of rated
tank capacity.
Decel Fuel Cutoff (DFCO) not active.
Fuel is not shutoff from high engine speed of 6500
rpm for manual transaxle vehicle.
Fuel is not shutoff at 255 km/h (158 mph).
Throttle position change is less than 3% per 125 ms.
Vehicle has not encountered an abusive engine
speed of 7000 rpm.Crankshaft speed patters are normal.
Throttle position is less than 4% when vehicle speed
is greater than 10 km/h (6 mph).
Engine speed is between 800 and 4500 rpm.
Vehicle voltage is between 11 and 16 volts.
Engine Coolant Temperature (ECT) is between –7°C
(20°F) and 120°C (248°F).
The engine speed is less than or equal to 1800 rpm or
the crank angle sensing error has not been learned.
There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
DTCs P0106, P0107, P0108, P0117, P0118, P0122,
P0123, P0320, P0337, P0341, P0342 and P0502 are
not set.
Action Taken when the DTC Sets
The malfunction Indicator Lamp (MIL) will blinking.
The ECM will record operating conditions at the time
the diagnostic fails. The information will be stored in
the Freeze Frame and failure records buffers.
A history DTC is stored.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
An intermittent can also be the result of a defective re-
luctor 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 inter-
mittent refer to “Symptoms Diagnosis” in this section.
DTC P0300 – Multiple Cylinder Misfire
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Turn the ignition ON, with the engine OFF.
3. Request Diagnostic Trouble Codes (DTCs)
Are DTCs P0201, P0202, P0203, P0204 set?
–Go to
Applicable DTC
table
Go to Step 3
3
Perform a visual/physical inspection.
Make any repairs that are necessary.
Is the repair complete?–
Go to Step 27Go to Step 4
4Start the engine and allow it to idle.
Are any Misfire Current counters incrementing?–
Go to Step 5Go to Step 6
5Are all counters equal (within a percentage of each
other)?–Go to Step 7Go to Step 11
Page 237 of 1184
ENGINE CONTROLS 1F–139
DAEWOO M-150 BL2
DIAGNOSTIC TROUBLE CODE (DTC) – P0300 MULTIPLE CYLINDER MISFIRE
System Description
The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is
misfiring. The ECM looks for a quick drop in crankshaft
speed. This test is executed in blocks of 100 engine rev-
olution tests. It may take between one to several tests to
store a Diagnostic Trouble Code (DTC) and illuminate
the Malfunction Indicator Lamp (MIL). Under light misfire
conditions, it may also take more than one trip to set a
DTC. Severe misfire will flash the MIL, indicating that
catalyst damage is possible.
Conditions for Setting the DTC
Emission threshold is 3.0% for automatic transaxle
and 3.0% for manual transaxle.
20 engine cycles have occurred since cranking has
started.
A/C compressor clutch has not just engaged or disen-
gaged.
Engine load and engine speed are in a detectable re-
gion and are at or above zero torque.
Camshaft Position (CMP) sensor is in synchroniza-
tion.
Electric Exhaust Gas Recirculation (EEGR) flow
diagnostic is not in progress.
Fuel level is greater than or equal to 20% of rated
tank capacity.
Decel Fuel Cutoff (DFCO) not active.
Fuel is not shutoff from high engine speed of 6500
rpm for manual transaxle vehicle or 6500 rpm in drive
and 6250 rpm in park for automatic transaxle ve-
hicles.
Fuel is not shutoff at 255 km/h (158 mph).
An automatic transmission is not shifting.
Throttle position change is less than 3% per 125 ms.
Vehicle has not encountered an abusive engine
speed of 7000 rpm.
Crankshaft speed patters are normal.Throttle position is less than 4% when vehicle speed
is greater than 10 km/h (6 mph).
Engine speed is between 600 and 4500 rpm.
Vehicle voltage is between 11 and 16 volts.
Engine Coolant Temperature (ECT) is between –7°C
(20°F) and 120°C (248°F).
The engine speed is less than or equal to 1800 rpm or
the crank angle sensing error has not been learned.
There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.
DTCs P0106, P0107, P0108, P0117, P0118, P0122,
P0123, P0320, P0337, P0341, P0342 and P0502 are
not set.
Action Taken when the DTC Sets
Emission related.
“Armed” after two trip with a fail.
“Disarmed” after one trip with a pass.
MIL on if failure is detected in three consecutive trips.
Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
Disconnecting the ECM battery feed for 10 seconds.
Diagnostic Aids
An intermittent can also be the result of a defective re-
luctor 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 inter-
mittent refer to “Symptoms Diagnosis” in this section.
DTC P0300 – Multiple Cylinder Misfire
StepActionValue(s)YesNo
1
Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Turn the ignition ON, with the engine OFF.
3. Request Diagnostic Trouble Codes (DTCs)
Are DTCs P0201, P0202, P0203, P0204 set?
–Go to
Applicable DTC
table
Go to Step 3
Page 244 of 1184
1F–146 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F170
DIAGNOSTIC TROUBLE CODE (DTC) – P0327 KNOCK SENSOR CIRCUIT FAULT
Circuit Description
The knock sensor(KS) system is used to detect engine
detonation, allowing the engine control module(ECM) to
retard ignition control spark timing based on the KS sig-
nal being received. The KS produces an AC signal so
that under a no knock condition the signal on the KS cir-
cuit measures about 0.007V AC. The KS signal’s ampli-
tude and frequency depend upon the amount of knock
being experienced. The ECM contains a non-replace-
able knock filter module called a signal-to-noise en-
hancement filter (SNEF) module. This filter module in
the ECM determines whether knock is occurring by
comparing the signal level on the KS circuit with the volt-
age level on the noise channel. The noise channel al-
lows the ECM to reject any false knock signal by
knowing the amount of normal engine mechanical noise
present. Normal engine noise varies depending on en-
gine speed and load. When the ECM determines that an
abnormally low noise channel voltage level is being ex-
perienced, a DTC P0327 will set.
Conditions for Setting the DTC
Knock sensor SPI bus in failure during 7 seconds.
The knock sensor voltage is below 0.2V.
Engine Coolant Temperature is higher than 80°C
(176°F).
Engine rpm is more than 2,500rpm.
Mass air flow is higer than 180mg/tdc.Action Taken When The DTCs Sets
The Malfunction Indicator Lamp (MIL) will illuminate.
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.
A history DTC is stored.
Conditions for Clearing the MIL/DTC
The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
DTC(s) can be cleared by using the scan tool.
DIAGNOSTIC AIDS
Check and correct any abnormal engine noise before
using the diagnostic table.
Any circuitry that is suspected as causing engine noise
complaint should be thoroughly checked for the follow-
ing conditions :
Backed-out terminals.
Improper mating.
Broken locks.
Improperly formed.
Damaged terminals.
Poor terminal-to-wire connections.
Physical damage to the wiring harness.