Page 505 of 2643
ENGINE CONTROLS 1F – 259
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
10Replace the VSS.
Is the action complete?–Go to Step 12–
11Replace the ECM.
Is the action complete?–Go to Step 12–
121. 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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 13Go to Step 2
13Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK
Page 506 of 2643

1F – 260IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0510
THROTTLE POSITION SWITCH CIRCUIT FAULT
(1.4L 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 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
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.
Page 507 of 2643

ENGINE CONTROLS 1F – 261
DAEWOO V–121 BL4
DTC P0510 – Throttle Position Switch Circuit Fault (1.4L DOHC)
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition switch to LOCK.
2. Disconnect the MTIA connector.
3. Disconnect the ECM connector.
4. Check for a short to ground or open in the wire
between the MTIA connector terminal 6 and
ECM connector terminal 55.
Is the problem found?–Go to Step 4Go to Step 3
3Check for a high voltage or open in the wire between
the MTIA connector terminal 6 and ECM connector
terminal 55.
Is the problem found?–Go to Step 4Go to Step 5
41. Turn the ignition switch to LOCK.
2. Repair the wire or the connector terminal as
needed.
3. Clear any DTCs from ECM.
4. Perform the diagnostic system check.(start en-
gine and turn LOCK).
Is the repair complete?–System OK–
51. Repair the short to battery voltage or ground in
the wire between the EVAP canister purge
valve connector terminal 2 and the ECM con-
nector terminal 79.
2. Clear any Diagnostic Trouble Codes (DTCs)
from the ECM.
3. Perform the diagnostic system check.
Is the repair complete?–Go to Step 6–
61. 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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 7Go to Step 2
7Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK
Page 508 of 2643

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.
Page 509 of 2643

ENGINE CONTROLS 1F – 263
DAEWOO V–121 BL4
DTC P0510 – Throttle Position Switch Circuit Fault (1.6L DOHC)
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition switch to LOCK.
2. Disconnect the MTIA connector.
3. Disconnect the ECM connector.
4. Check for a short to ground or open in the wire
between the MTIA connector terminal 6 and
ECM connector terminal 55.
Is the problem found?–Go to Step 4Go to Step 3
3Check for a high voltage or open in the wire between
the MTIA connector terminal 6 and ECM connector
terminal 55.
Is the problem found?–Go to Step 4Go to Step 5
41. Turn the ignition switch to LOCK.
2. Repair the wire or the connector terminal as
needed.
3. Clear any DTCs from ECM.
4. Perform the diagnostic system check.(start en-
gine and turn LOCK).
Is the repair complete?–System OK–
51. Repair the short to battery voltage or ground in
the wire between the EVAP canister purge
valve connector terminal 2 and the ECM con-
nector terminal 79.
2. Clear any Diagnostic Trouble Codes (DTCs)
from the ECM.
3. Perform the diagnostic system check.
Is the repair complete?–Go to Step 6–
61. 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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 7Go to Step 2
7Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK
Page 510 of 2643

1F – 264IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0532
A/C PRESSURE SENSOR LOW VOLTAGE
Circuit Description
The Air Conditioning (A/C) system uses an A/C refrigerant
pressure sensor mounted in the high pressure side of the
A/C refrigerant system to monitor A/C refrigerant pres-
sure. The Engine Control Module (ECM) uses this infor-
mation to turn ON the engine coolant fans when the A/C
refrigerant pressure is high and to keep the compressor
disengaged when A/C refrigerant pressure is excessively
high or low.
The Air Conditioning Pressure (ACP) sensor operates like
other 3–wire sensors. The ECM applies a 5.0 volt refer-
ence and a sensor ground to the sensor. Changes in the
A/C refrigerant pressure will cause the ACP sensor input
to the ECM to vary. The ECM monitors the ACP sensor
signal circuit and can determine when the signal is outside
of the possible range of the sensor. When the signal is out
of range for a prolonged period of time, the ECM will not
allow the A/C compressor clutch to engage. This is done
to protect the compressor.
Conditions for Setting the DTC
S A/C pressure is less than 12.16 kpa.
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.
S The A/C compressor operation will be disabled
while the low voltage indication exists.
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
Inspect harness connectors for backed–out terminals, im-
proper mating, broken locks, improperly formed or dam-
aged terminals, and poor terminal–to–wire connection at
the ECM.
Inspect the wiring harness for damage. If the harness ap-
pears to be OK, observe the A/C pressure display on the
scan tool while moving the connectors and wiring har-
nesses related to the A/C Pressure sensor. A change in
the A/C pressure display will indicate the location of the
fault.
If DTC P0532 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 set occurs. This may assist in diagnosing the
condition.
Page 511 of 2643

ENGINE CONTROLS 1F – 265
DAEWOO V–121 BL4
DTC P0532 – A/C Pressure Sensor Low Voltage
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. Idle the engine.
Does the scan tool display Air Conditioning Pressure
(ACP) sensor voltage below the specified value?0.06 VGo to Step 3Go to Step 4
31. Turn the ignition OFF.
2. Disconnect the ACP sensor connector.
3. Jumper the ACP signal circuit, terminal 2 to the
5 volt reference circuit, terminal 1.
4. Turn the ignition switch on.
Does the ACP voltage read more than the specified
value?4.9 VGo to Step 5Go to Step 6
41. Turn the ignition ON, with the engine OFF.
2. Operate the vehicle within the Failure Record
conditions and Conditions For Setting the DTC
as noted.
Does the scan tool display ACP voltage below the
specified value?0.06 VGo to Step 3Go to
”Diagnostic
Aids”
5Inspect the ACP sensor harness connector termi-
nals for the following conditions:
S Poor connections
S Proper contact tension
S Poor terminal–to–wire connection
Is a problem found?–Go to Step 8Go to Step 9
61. Turn the ignition OFF.
2. Remove the jumper wire.
3. Probe the ACP sensor signal circuit terminal 2
with a test light to B+.
4. Turn the ignition ON.
Does the scan tool read over the specified value?4 VGo to Step 7Go to Step 11
7Check the ACP sensor 5 volt reference circuit for an
open or short to ground and repair as needed.
Is the repair complete?–Go to Step 13Go to Step 10
8Repair the connection terminals as necessary.
Is the repair complete?–Go to Step 13–
91. Turn the ignition OFF.
2. Replace the ACP sensor.
Is the repair complete?–Go to Step 13–
101. Turn the ignition OFF.
2. Replace the engine control module (ECM).
Is the repair complete?–Go to Step 13–
Page 512 of 2643
1F – 266IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
11Check the ACP sensor signal circuit for the following
conditions:
S Open
S Short to ground
S Short to sensor ground
Is a problem found?–Go to Step 12Go to Step 10
12Repair the A/C Pressure sensor signal circuit.
Is the repair complete?–Go to Step 13–
131. 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 14Go to Step 2
14Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK