2004 DAEWOO LACETTI Throttle body

1F – 262IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0510
THROTTLE POSITION SWITCH CIRCUIT FAULT
(1.6L DOHC)
Circuit Description
The aim of the MTIA(Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (05, 195). The charac-
teristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TP sensor is lower for small
angles that permits to be more precise during the idle
speed control. Out of idle speed the throttle is actuated
mechanically by a classical bowdencable.
This switch indicates throttle plate in idle position when
contact closed. This switch is fixed at the DC–motor drive
and the throttle plate closes the contact in dependence to
the actual motor drive position.
Conditions for Setting the DTC
S The engine stopped and ignition switch turned ON.
S DTCs P0122, P0123, P0222 and P0223 are not
set.
S MTIA output signal is highter than throttle position +
2.5° and throttle position is open at least 0.2 sec-
onds.
Or
S DTCs P0122, P0123, P0222, and P0223 are not
set.
S The throttle position output signal is greater than
30° and throttle position is closed at least 2 sec-
onds.
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.
S Coolant fan turns on.
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 Using the scan tool can clear DTC(s).
S Disconnecting the ECM battery feed for 10 sec-
onds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
VSS signal circuit 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
Ensure the VSS is correctly torqued to the trnasaxle hous-
ing.
Refer to ”Intermittents” in this section.

1F – 316IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1511
IDLE CHARGE ACTUATOR CIRCUIT FAULT
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (0°, 19°). The charac-
teristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical accelcable.
The DC–motor commands the actuator for idle
Conditions for Setting the DTC
S The engine is running.
S The throttle position is set between 0.25 and 5.65.
S DTCs P0222 and P0223 are not set.
S The reference range of MTIA higher than 59.5% or
less than –70% for longer than 5 seconds.
(1.4L DOHC)
S The reference range of MTIA higher than 35% or
less than –35% at least 5 seconds. (1.6L DOHC)
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.S The ECM will record operating conditions at the
time the diagnostic fail. This information will be
stored in the Freeze Frame and Failure Records
buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
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

ENGINE CONTROLS 1F – 317
DAEWOO V–121 BL4
DTC P1511 – Idle Charge Actuator Circuit Fault
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
2Turn the Turn the ignition switch to ON.
Is the Malfunction Indicator Lamp(MIL) on steady?–Go to Step 4Go to Step 3
31. Connect the scan tool the DLC.
2. Turn the Turn the ignition switch to ON.
Does the scan tool display serial data?–Go to Step 4Try with
another scan
tool
4Start the engine.
Does the engine start?–Go to Step 5Go to
”Engine Cranks
But Will Not
Run”
51. Turn the ignition switch to LOCK.
2. Connect the scan tool to the DLC.
3. Turn the Turn the ignition switch to ON.
Are any Diagnostic Trouble Codes (DTCs) dis-
played?–Go to Step 6Try with
another scan
tool
6Refer to the applicable DTC table.
Is only one DTC identified as valid trouble code
P1511?–Go to Step 7Go to Applica-
ble DTC Table
and Go to
”Multiple DTC”
71. Turn the ignition switch to LOCK.
2. Disconnect the MTIA connector.
3. Disconnect the ECM connector.
4. Measure resistance between MTIA connector
terminal 4 and ECM connector terminal 43.
Does the resistance measure with the value speci-
fied?0WGo to Step 8Go to Step 9
8Measure resistance between MTIA connector termi-
nal 8 and ECM connector terminal 19.
Does the resistance measure within the value speci-
fied?0WGo to Step 10Go to Step 11
91. Repair the wire or the connector terminal as
needed.
S Clear any DTCs from ECM.
S Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 8
101. Repair the wire or the connector terminal as
needed.
S Clear any DTCs from ECM.
S Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 11
111. Turn the ignition switch to LOCK.
2. Replace the throttle body assembly.
S Clear any DTCs from ECM.
S Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 12

ENGINE CONTROLS 1F – 319
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1512
IDLE CHARGE ACTUATOR MECHANICAL ERROR
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (0°, 19°). The charac-
teristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical accelcable.
The DC–motor commands the actuator for idle
Conditions for Setting the DTC
S The engine is running.
S The MTIA set point is between 0.25 and 5.65.
S DTCs P0222 and P0223 are not set.
S The reference range of MTIA higher than 59.5% or
less than –70% for longer than 10 seconds.
(1.4L DOHC)
S The reference range of MTIA higher than 35% or
less than –35% at least 10seconds. (1.6L DOHC)
S Mechanical problems exists.
– problem of accel cable hose
– problem inside MTIA : seizing by friction,
snooted, fouling.
Action Taken When the DTC SetsS The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.
S The ECM will record operating conditions at the
time the diagnostic fail. This information will be
stored in the Freeze Frame and Failure Records
buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.
S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
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

1F – 320IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P1512 – Idle Charge Actuator Mechanical Error
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
2Turn the Turn the ignition switch to ON.
Is the Malfunction Indicator Lamp(MIL) on steady?–Go to Step 4Go to Step 3
31. Connect the scan tool the DLC.
2. Turn the Turn the ignition switch to ON.
Does the scan tool display serial data?–Go to Step 4Try with
another scan
tool
4Start the engine.
Does the engine start?–Go to Step 5Go to
”Engine Cranks
But Will Not
Run”
51. Turn the ignition switch to LOCK.
2. Connect the scan tool to the DLC.
3. Turn the Turn the ignition switch to ON.
Are any Diagnostic Trouble Codes (DTCs) dis-
played?–Go to Step 6Try with
another scan
tool
6Refer to the applicable DTC table.
Is only one DTC identified as valid trouble code
P1512?–Go to Step 7Go to Applica-
ble DTC Table
and Go to
”Multiple DTC”
7Check if the accel cable of MTIA is not on accel cable
stop repair the accel cable as necessary.
Is it necessary?–Go to Step 9Go to Step 8
81. Turn the ignition switch to LOCK.
2. Replace the throttle body assembly.
3. Clear any DTCs from ECM.
4. Perform the diagnostic system check.
Is the repair complete?–Go to Step 10–
91. Using the scan tool, clear the Diagnostic
Trouble Codes (DTCs).
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the Conditions for
setting this DTC as specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 10Go to Step 2
10Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 321
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1513
IDLE CHARGE ACTUATOR FUNCTIONAL ERROR
Circuit Description
The aim of the MTIA (Main Throttle Idle Actuator) is to con-
trol the idle speed with the throttle body itself. The throttle
is motorized for low opening angle (0°, 19°). The charac-
teristics of the air flow are not the same for low and high
opening angles. As a matter of fact, the gradient of the
mass air flow function of TPS is lower for small angles that
permits to be more precise during the idle speed control.
Out of idle speed the throttle is actuated mechanically by
a classical accelcable.
The DC–motor commands the actuator for idle
Conditions for Setting the DTC
S Mechanical problems exists.
– problem of accel cable hose
– problem inside MTIA : seizing by friction,
snooted, fouling.
S Absolute adaptation or relative is not correct after
16 attemps.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
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

1F – 322IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P1513 – Idle Charge Actuator Functional Error
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
2Turn the Turn the ignition switch to ON.
Is the Malfunction Indicator Lamp(MIL) on steady?–Go to Step 4Go to Step 3
31. Connect the scan tool the DLC.
2. Turn the Turn the ignition switch to ON.
Does the scan tool display serial data?–Go to Step 4Try with
another scan
tool
4Start the engine.
Does the engine start?–Go to Step 5Go to
”Engine Cranks
But Will Not
Run”
51. Turn the ignition switch to LOCK.
2. Connect the scan tool to the DLC.
Turn the Turn the ignition switch to ON.
Are any Diagnostic Trouble Codes (DTCs) dis-
played?–Go to Step 6Try with
another scan
tool
6Refer to the applicable DTC table.
Is only one DTC identified as valid trouble code
P1513?–Go to Step 7Go to Applica-
ble DTC Table
and Go to
”Multiple DTC”
71. Turn the ignition switch to LOCK.
2. Disconnect the MTIA connector.
3. Disconnect the ECM connector.
4. Measure resistance between MTIA connector
terminal 4 and ECM connector terminal 43.
Does the resistance measure with the value speci-
fied?0WGo to Step 8Go to Step 9
8Measure resistance between MTIA connector termi-
nal 8 and ECM connector terminal 19.
Does the resistance measure within the value speci-
fied?0WGo to Step 10Go to Step 11
91. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 8
101. Repair the wire or the connector terminal as
needed.
2. Clear any DTCs from ECM.
3. Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 11
111. Turn the ignition switch to LOCK.
2. Replace the throttle body assembly.
S Clear any DTCs from ECM.
S Perform the diagnostic system check.
Is the repair complete?–System OKGo to Step 12

1F – 402IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
61. Disconnect the Manifold Absolute Pressure
(MAP) sensor electrical connector.
2. Operate the vehicle in Closed Loop while moni-
toring the Long Term Fuel Trim value.
Is the Long Term Fuel Trim value below the specified
value?25%Go to Step 15Go to Step 9
71. Repair the malfunction found in Step 5.
2. Recheck the Long Term Fuel Trim value while
operating the engine.
Is the Long Term Fuel Trim value below the specified
value?25%Go to Step 8Go to Step 9
8Lean condition is not present.
Does a driveability problem exist?–Go to
”Symptom
Diagnosis”Go to Step 16
91. Visually/physically inspect the following items
for vacuum leaks:
S Intake manifold.
S Throttle body.
S Injector O–rings.
2. Repair any leaks found as necessary.
Is the repair complete?–Go to Step 16Go to Step 10
10Allow the engine to idle.
Are the Idle Air Control (IAC) counts above the spe-
cified value?5Go to Step 11Go to Step 12
11Check the fuel for excessive water, alcohol, or other
contaminants and correct the contaminated fuel
condition if present.
Is the repair complete?–Go to Step 16Go to Step 13
12Check the IAC valve performance. Refer to ”DTC
P0506 Idle Speed RPM Lower Than Desired Idle
Speed” or ”DTC P0507 Idle Speed RPM Higher
Than Desired Idle Speed” in this section and repair
as necessary.
Is the repair complete?–Go to Step 16Go to Step 13
131. Connect a fuel pressure gauge to the fuel sys-
tem.
2. Turn the ignition OFF for at least 10 seconds.
3. Turn the ignition ON, with the engine OFF. The
fuel pump will run for approximately 2–3 sec-
onds. It may be necessary to cycle the ignition
switch ON more than once to obtain maximum
fuel pressure.
4. Note the fuel pressure with the fuel pump run-
ning. The pressure should be within the speci-
fied value. When the fuel pump stops, the pres-
sure may vary slightly then hold steady.
Is the fuel pressure steady and does the fuel pres-
sure hold?241–276 kPa
(35–40 psi)Go to Step 14Go to
”Fuel System
Diagnosis”