ESP DAEWOO NUBIRA 2004 Service User Guide

1F – 346IENGINE CONTROLS
DAEWOO V–121 BL4
DTCIlluminate MIL Type Description
P1392G Sensor Rough Road Low VoltageCnlNo
P1393G Sensor Rough Road High VoltageCnlNo
P1396ABS WSS Signal VariationCnlNo
P1397ABS WSS No SignalCnlNo
P1404Exhaust Gas Recirculation Closed Valve Pintle ErrorEYe s
P1601SPI Communications Between ECM and TCMAYe s
P1607Lower Power Counter ResetCnlNo
P1626Immobilizer No ResponseCnlNo
P1631Immobilizer Incorrect ResponseCnlNo
P1650SPI Communications Between Error with SIDM ChipCnlNo
P1655SPI Communications Between Error with PSVI ChipEYe s

ENGINE CONTROLS 1F – 347
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0106
MANIFOLD ABSOLUTE PRESSURE RATIONALITY
Circuit Description
The Engine Control Module (ECM) uses the Manifold Ab-
solute Pressure (MAP) sensor to control the fuel delivery
and the ignition timing. The MAP sensor measures the
changes in the intake manifold pressure which results
from engine load (intake manifold vacuum) and the rpm
changes, and it converts these into voltage outputs. The
ECM can detect if the MAP sensor is not responding to the
Throttle Position (TP) changes by comparing the actual
MAP change to a predicted MAP change based on the
amount of TP change that occurs. If the ECM does not see
the expected MAP change or more, DTC P0106 will set.
Conditions for Setting the DTC
S Altitude compensated MAP reading is higher than
high threshold or lower than low threshold table
based on rpm and TP signal.
S DTCs P0107, P0108, P0117, P0118, P0122,
P0123, P0201, P0202, P0203, P0204, P0300,
P0351, P0352, P0402, P0404, P1404, P0405,
P0406, P0506, P0507 are not set.
S Engine running.
S Valid Barometric Pressure (BARO) update.
S Torque Converter Clutch (TCC) steady (A/T).
S A/C steady state.
S No TP sensor fail conditions present.
S No MAP fail conditions present.
S Change in Idle Air Control (IAC) is less than 5%.
S Coolant temperature is greater than –10°C (14°F).
S Change in rpm is less than 200.
S Change in TP sensor is less than 3%.
S Change in Exhaust Gas Recirculation (EGR) value
is less than 6%.
S The rpm is between 1300 and 4500.
S All of the above are stabilized for 1.5 seconds.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
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.
S The ECM will substitute a fixed MAP value and use
TP sensor to control the fuel delivery. (The scan
tool will not show defaulted value.)
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
With the ignition ON and the engine stopped, the manifold
pressure is equal to atmospheric pressure and the signal
voltage will be high. This information is used by the ECM
as an indication of vehicle altitude. Comparison of this
reading with a known good vehicle with the same sensor
is a good way to check the accuracy of a suspect sensor.
Readings should be the same +0.4 volt.
The MAP sensor vacuum source should be thoroughly
checked for restrictions at the intake manifold.
Test Description
Numbers below refer to the step numbers on the Diagnos-
tic 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 occurred. The information is then stored on the
scan tool for later reference.
2. A sensor that displays an ignition ON, engine OFF
BARO value that does not appear normal for the
altitude the vehicle is in should be considered to be
malfunctioning.
3. While starting the engine, the MAP sensor should
detect any changes in the manifold pressure. This
test is to determine if the sensor is stuck at a value.
4. A normal MAP sensor will react as quickly to the
throttle changes as they can be made. A sensor
should not appear to be lazy or catch up with the
throttle movements.
5. This step checks if the reason for no MAP change
was due to a faulty sensor or vacuum source to the
sensor.
6. The MAP sensor vacuum source should be thor-
oughly checked for restrictions. A drill bit can be
used to clean out any casting flash that may exist in
the vacuum port.
7. The MAP sensor vacuum source should be thor-
oughly checked for restrictions. A drill bit can be
used to clean out any casting flash that may exist in
the vacuum port.
9. The MAP Sensor System Performance diagnostic
may have to complete several tests before deter-
mining if the diagnostic has passed or failed the last
test. Operate the vehicle in the Conditions for Set-
ting the DTC several times to ensure that the diag-
nostic runs enough tests to pass or fail.
10. If no faults have been found at this point and no
additional DTCs were set, refer to ”Diagnostic
Aids”in this section for additional checks and infor-
mation.

1F – 378IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0133
FRONT HEATED OXYGEN SENSOR (HO2S1) SLOW
RESPONSE
Circuit Description
The Engine Control Module (ECM) continuously monitors
the Front Heated Oxygen Sensor (HO2S1) activity for 100
seconds. During the monitor period, the ECM counts the
number of times that the HO2S1 switches from rich to lean
and from lean to rich and adds the amount of time it took
to complete all switches. With this information, an average
time for all switches can be determined. If the average time
to switch is too out of specification, a DTC P0133 will set.
If the HO2S1 pigtail wiring, connector, or terminal is dam-
aged, the entire HO2S1 assembly must be replaced. Do
not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly, it must have a
clean air reference provided to it. This clean air reference
is obtained by way of the HO2S1 wire(s). Any attempt to
repair the wires, connector, or terminals could result in the
obstruction of the air reference and degrade HO2S1 per-
formance.
Conditions for Setting the DTCS HO2S1 average transition time between 0.3–0.6
volts, lean to rich is greater than 156 millisec-
onds(A/T) or rich to lean is greater than 140 milli-
seconds (M/T).
S Closed loop stoichiometry.
S Engine Coolant Temperature (ECT) is greater than
70°C (158°F).
S System voltage is greater than 10 volts.
S Engine run time is greater than 60 seconds.
S Purge Duty Cycle (DC) is less than 20%.
S The rpm is between 1600 and 4300.
S Airflow is between 9 and 40 g/sec.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0131, P0132, P0134, P0135,
P1167, P0171, P1171, P0172, P0201, P0202,
P0203, P0204, P0300, P0336, P0337, P0351,
P0352, P0402, P0404, P0405, P0406, P0506,
P0507, P1404, and P0443 are not set.
S 2 second delay after conditions are met.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.

ENGINE CONTROLS 1F – 379
DAEWOO V–121 BL4
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.
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
DTC P0133 or slow response is most likely caused by one
of the following items:
S Fuel pressure – The system will go rich if fuel pres-
sure is too high. The ECM can compensate for
some increase, but if it gets too high, a DTC P0133
may set. Refer to”Fuel System Diagnosis” in this
section.
S Leaking injector – A leaking or malfunctioning injec-
tor can cause the system to go rich.
S Manifold Absolute Pressure (MAP) sensor – An
output that causes the ECM to sense a higher than
normal manifold pressure (low vacuum) can cause
the system to go rich. Disconnecting the MAP sen-
sor will allow the ECM to set a fixed value for the
MAP sensor. Substitute a different MAP sensor if
the rich condition is gone while the sensor is dis-
connected.S Pressure regulator – Check for a leaking fuel pres-
sure regulator diaphragm by checking for the pres-
ence of liquid fuel in the vacuum line to the pres-
sure regulator.
S Throttle Position (TP) sensor – An intermittent TP
sensor output can cause the system to go rich due
to a false indication of the engine accelerating.
S HO2S1 contamination – Inspect HO2S1 for silicone
contamination from fuel or use of improper room
temperature vulcanizing (RTV) sealant. The sensor
may have a white powdery coating, resulting in a
high but false voltage signal (rich exhaust indica-
tion). The ECM will then reduce the amount of fuel
delivered to the engine causing a severe surge or
driveability problem.
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.
14. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
17. If no malfunctions have been found at this point and
no additional DTCs were set, refer to ”Diagnostic
Aids” for additional checks and information.
DTC P0133 – Front Heated Oxygen Sensor (HO2S1) Slow
Response
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”
21. Install a scan tool to the Data Link Connector
DLC).
2. Turn the ignition ON.
Are any additional Diagnostic Trouble Codes
(DTCs) set?–Go to
”Applicable
DTC table”Go to Step 3
31. Start the engine and idle at normal operating
temperature.
2. Operate the vehicle within the specified param-
eter under the Conditions For Setting the DTC.
3. Using the scan tool monitor the specific DTC
information for DTC P0133 until DTC P0133
test run.
Does the scan tool indicate DTC P0133 failed this
ignition cycle?–Go to Step 4Go to
”Diagnostic
Aids”

ENGINE CONTROLS 1F – 447
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0325
KNOCK SENSOR INTERNAL MALFUNCTION
System Description
The Knock Sensor (KS) system is used to detect engine
detonation, allowing the Engine Control Module (ECM) to
retard the ignition control spark timing based on the KS
signal being received. The KS produces an AC signal so
that under a no–knock condition the signal on the KS cir-
cuit measures about 0.007 volts AC. The KS signal’s am-
plitude and frequency depend upon the amount of knock
being experienced. The ECM contains a nonreplaceable
knock filter module called a Digitally Controlled Signal–to–
Noise Enhancement Filter (DSNEF) module. This filter
module in the ECM determines whether or not knock is oc-
curring by comparing the signal level on the KS circuit with
the voltage level on the noise channel. The noise channel
allows the ECM to reject any false knock signal by knowing
the amount of normal engine mechanical noise present.
Normal engine noise varies depending on engine speed
and load. When the ECM determines that an abnormally
low noise channel voltage level is being experienced,
Diagnostic Trouble Code (DTC) P0325 will set.
Conditions for Setting the DTC
S DSNEF A/D reading is less than 1.0% or greater
than 80% any of the 4 cylinders.
S Vacuum is less than the predetermined value (10 to
50 kPa, based on rpm).
S The rpm is greater than 1600.
S DTC(s) P0106, P0107, P0108 are not set.
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 Failure Records buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTCS 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 and correct any abnormal engine noise before us-
ing the diagnostic table.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions:
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
S Physical damage to the wiring harness
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.
2. If the conditions for the test as described above are
met, a DTC P0325 will set and MIL will illuminate.
4. If the engine has an internal knock or audible noise
that causes a knocking type noise on the engine
block, the knock sensor may be responding to the
noise.
6. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.
DTC P0325 – Knock Sensor Internal Malfunction
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”
21. Install a scan tool to the Data Link Connector
(DLC).
2. Clear the Diagnostic Trouble Codes (DTCs).
3. Start the engine.
4. Operate the vehicle within the Conditions for
Setting the DTC as noted.
Is the DTC set again.–Go to Step 3Go to Step 6

ENGINE CONTROLS 1F – 449
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0327
KNOCK SENSOR CIRCUIT FAULT
System Description
The Knock Sensor (KS) system is used to detect engine
detonation, allowing the Engine Control Module (ECM) to
retard the ignition control spark timing based on the KS
signal being received. The KS produces an AC signal so
that under a no–knock condition the signal on the KS cir-
cuit measures about 0.007 volts AC. The KS signal’s am-
plitude and frequency depend upon the amount of knock
being experienced. The ECM monitors the KS signal and
can diagnose the KS and circuitry.
Conditions for Setting the DTC
S Minimum difference between cylinders is greater
than 0.4%.
S Vacuum is less than the predetermined value (10 to
50 kPa, based on rpm).
S The rpm is greater than 1600.
S DTC(s) P0106, P0107, P0108 are not set.
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 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 DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.Diagnostic Aids
Check and correct any abnormal engine noise before us-
ing the diagnostic table.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions:
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
S Physical damage to the wiring harness
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.
2. If the conditions for the test as described above are
met, a DTC P0327 will set and MIL will illuminate.
3. If the engine has an internal knock or audible noise
that causes a knocking type noise on the engine
block, the KS may be responding to the noise.
5. Checking the internal resistance of the KS or the
wiring to the KS is OK.
6. Any circuitry, that is suspected as causing the com-
plaint, should be thoroughly checked for backed–
out terminals, improper mating, broken locks, im-

1F – 484IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0420
CATALYST OXYGEN SENSOR LOW EFFICIENCY
Circuit Description
In order to control exhaust emissions of Hydrocarbons
(HC), Carbon Monoxide (CO) and Nitrogen Oxide (NOx),
a Three–Way Catalytic Converter (TWC) is used. The cat-
alyst within the converter promotes a chemical reaction
which oxidizes the HC and CO present in the exhaust gas,
converting them into harmless water vapor and carbon
dioxide, it also reduces NOx, converting it into nitrogen.
The catalytic converter also has the ability to store oxygen.
The Engine Control Module (ECM) has the capability to
monitor this process using a Heated
Rear Heated Oxygen Sensor (HO2S2) located in the ex-
haust stream past the TWC. The HO2S2 produces an out-
put signal which indicates the oxygen storage capacity of
the catalyst; this in turn indicates the catalyst’s ability to
convert exhaust emissions effectively. The ECM monitors
the catalyst efficiency by first allowing the catalyst to heat
up, waiting for a stabilization period while the engine is id-
ling, and then adding and removing fuel while monitoring
the reaction of the HO2S2. When the catalyst is function-
ing properly, the HO2S2 response to the extra fuel is slow
compared to the Front Heated Oxygen Sensor (HO2S1).
When the HO2S2 response is close to that of the HO2S1,
the Oxygen storage capability or efficiency of the catalyst
is considered to be bad, and the Malfunction Indicator
Lamp (MIL) will illuminate.
Conditions for Setting the DTC
S Oxygen storage capacity index time is less than 0.3
seconds.
S Before idle test, the vehicle needs to be driven for
at least:
S 15 seconds at airflow is greater than 9.2 g/sec.
for manual transaxle.
S 11 seconds at airflow is greater than 12 g/sec
for automatic transaxle.
S Oxygen Sensor Capacity test condition:
S Closed loop stoichiometry.
S Purge concentration learned.
S Engine is running more than 330 seconds.
S Airflow is between 2.5 and 7.25 g/sec.
S Throttle Position (TP) sensor is less than 1.5%.
S Intake Air Temperature (IAT) is between –7°C
(19.4°F) and 105°C (221°F).
S Barometric pressure (BARO) is greater than 72 kPa
(10.4 psi).
S Catalyst temperature is between 500°C (932°F)
and 850°C (1562°F) for automatic transaxle.
S Catalyst temperature is between 450°C (842°F)
and 850°C (1562°F) for automatic transaxle.
S Closed Loop integrator change is less than 0.03.
S Idle time is less than 1 minute.
S Vehicle speed is less than 3 km/h (1.9 mph).S Block Learn Mode is learned.
S Above condition is stabilized for 5 seconds.
Note : Test is aborted for this idle if:
S Change in engine speed is greater than 80 rpm.
S A/C status changed.
S Cooling fan status changed.
S Insufficient air/fuel shift.
S DTC(s) P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0131, P0132, P0133, P1133,
P0134, P0135, P0137, P0138, P0140, P0141,
P1167, P1171, P0171, P0172, P0201, P0202,
P0203, P0204, P0300, P0336, P0337, P0341,
P0342, P0351, P0352, P0402, P0404, P1404,
P0405, P0406, P0443, P0502, P0506, P0507, and
P0562 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
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
The catalyst test may abort due to a change in the engine
load. Do not change the engine load (i.e. A/C, coolant fan,
heater motor) while a catalyst test is in progress.
An intermittent problem may be caused by a poor connec-
tion, rubbed–through wire insulation, or a wire that is bro-
ken inside the insulation.
Any circuitry, that is suspected as causing the intermittent
complaint, should be thoroughly checked for the following
conditions:
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminal–to–wire connection
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Table.

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.

ENGINE CONTROLS 1F – 543
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1134
FRONT HEATED OXYGEN SENSOR (HO2S1)
TRANSITION RATIO
Circuit Description
The Engine Control Module (ECM) monitors the Front
Heated Oxygen Sensor (HO2S1) activity for 100 seconds
after closed loop and stoichiometric operation have been
established. During the monitoring period the ECM counts
the number of times that the HO2S1 responds from rich
to lean and adds the amount of time it took to complete all
transitions. With this information, an average time for all
transitions can be determined. The ECM then divides the
–to–lean average by the lean–to–rich average to obtain
the ratio. If the HO2S1 transition time ratio is not within the
range, Diagnostic Trouble Code (DTC) P1134 will be set,
indicating that the HO2S1 is not responding as expected
to changes in exhaust oxygen content.
Conditions for Setting the DTC
S HO2S1 rich–to–lean and lean–to rich transition ratio
is out of specification(between 0.375 and 3.5).
S Closed Loop stoichiometry.
S Engine Coolant Temperature (ECT) is greater than
70°C (158°F).
S System voltage is greater than 10 volts.
S Engine run time is greater than 60 seconds.
S Purge Duty Cycle (DC) is less than 20%.S Engine speed is between 1600 and 4300 rpm.
S Calculated airflow is between 9 and 40 g/sec.
S DTCs P0106, P0107, P0108, P0117, P0118,
P0122, P0123, P0131, P0132, P0134, P0135,
P1167, P0171, P1171, P0172, P0201, P0202,
P0203, P0204, P0300, P0336, P0337, P0351,
P0352, P0402, P0404, P1404, P0405, P0406,
P0506, P0507, and P0443 are not set.
S 2 second delay after conditions are met.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
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.
S The vehicle will operate in Open Loop.
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.