1F – 242IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0463 – Fuel Level Sensor High Voltage (1.6L DOHC Only)
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 ON.
2. Install a scan tool.
3. Operate the vehicle within Freeze Frame con-
ditions as noted.
Is the Diagnostic Trouble Code (DTC) P0463 set?–Go to Step 3Go to
”Diagnostic
Aids”
31. Disconnect the fuel sender electircal connector
from the fuel pump.
2. Using a digital voltmeter (DVM), measure the
voltage in the signal circuit at terminal 1.
Is the voltage within the specified value?0.2–4.8VGo to Step 4Go to Step 6
4Check for a proper ground connection at the fuel
tank and repair as necessary.
Is a repair necessary?–Go to Step 11Go to Step 5
51. Remove the fuel sender from the fuel tank.
2. Reconnect the fuel pump electrical connector.
3. Monitor the Fuel Level Sensor parameter on
the scan tool while moving the Fuel Level Sen-
sor float from the empty position to the full
position.
4. Repeat the procedure several times.
Does the Fuel Level Sensor value on the scan tool
increase and then decrease steadily when the float
is moved?–Go to
”Diagnostic
Aids”Go to Step 8
6Check for an open or short to battery voltage in the
Fuel Level Sensor circuit and repair as necessary.
Is the repair necessary?–Go to Step 11Go to Step 9
7Repair the open or short to battery voltage in the
Fuel Level Sensor circuit between the Fuel Level
Sensor harness connector and the Fuel Level Sen-
sor.
Is the repair complete?–Go to Step 11–
8Replace the fuel sender assembly.
Is the replacement complete?–Go to Step 11–
91. Connect the fuel sender electrical connector.
2. Disconnect the engine control module(ECM)
connector.
3. Using a digital voltmeter (DVM) measure the
voltage in the signal circuit, at terminal 46.
Does the DVM read within the specified value?0.2–4.8VGo to Step 10Go to
Section 9E, In-
strumentation/
Driver Informa-
tion
10Replace the ECM.
Is the repair complete?–Go to Step 11–
ENGINE CONTROLS 1F – 245
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0480
LOW SPEED COOLING FAN RELAY CIRCUIT FAULT
(1.4L DOHC)
Circuit Description
Ignition voltage is supplied directly to the cooling fan relay
coil. The engine control module(ECM) controls the relay
by grounding the control circuit via an internal switch called
a driver. The primary function of the driver is supply the
ground for the component being controlled. Each driver
has a fault line which is monitored by the ECM. When the
ECM is commanding a component ON, the voltage of the
control circuit should be low (near 0volts). When the ECM
is commanding the control circuit to a component OFF, the
voltage potential of the circuit should be high(near battery
voltage). If the fault detection circuit senses a voltage oth-
er than what is expected, the fault line status will change
causing the DTC to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the relay.
Conditions for Setting the DTC
S The low speed cooling fan control circuit is an open
or a short to battery to ground condition exist.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate after three consecutive trip with a fail.S The ECM will record operating conditions ant 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 10 sec-
onds.
Diagnostic Aids
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot be
duplicated, the information included in the Freeze Frame
and/or failure records data can be useful in determining
how many miles since the DTC set. The fail counter and
Pass Counter can also be used to determine how many
ignition cycles the diagnostics reported a Freeze Frame
conditions (rpm, load, vehicle speed, temperature, etc.)
that .are noted. This will isolate when the DTC failed.
DTC P0480 – Low Speed Cooling Fan Relay 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 ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when command-
ed?–Go to Step 3Go to Step 5
31. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in low speed relay control circuit, at ter-
minal 10 to ground for 2 minutes.
Does the amperage measure less than the specified
value?0.75 ampsGo to
”Diagnostic
Aids”Go to Step 6
1F – 248IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0480
LOW SPEED COOLING FAN RELAY CIRCUIT FAULT
(1.6L DOHC)
Circuit Description
Ignition voltage is supplied directly to the cooling fan relay
coil. The engine control module(ECM) controls the relay
by grounding the control circuit via an internal switch called
a driver. The primary function of the driver is supply the
ground for the component being controlled. Each driver
has a fault line which is monitored by the ECM. When the
ECM is commanding a component ON, the voltage of the
control circuit should be low (near 0volts). When the ECM
is commanding the control circuit to a component OFF, the
voltage potential of the circuit should be high(near battery
voltage). If the fault detection circuit senses a voltage oth-
er than what is expected, the fault line status will change
causing the DTC to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the relay.
Conditions for Setting the DTC
S The low speed cooling fan control circuit is an open
or a short to battery or a short to ground condition
exist.
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
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot be
duplicated, the information included in the Freeze Frame
and/or failure records data can be useful in determining
how many miles since the DTC set. The fail counter and
Pass Counter can also be used to determine how many
ignition cycles the diagnostics reported a Freeze Frame
conditions (rpm, load, vehicle speed, temperature, etc.)
that .are noted. This will isolate when the DTC failed.
DTC P0480 – Low Speed Cooling Fan Relay 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 ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when command-
ed?–Go to Step 3Go to Step 5
31. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in low speed relay control circuit, at ter-
minal 10 to ground for 2 minutes.
Does the amperage measure less than the specified
value?0.75 ampsGo to
”Diagnostic
Aids”Go to Step 6
ENGINE CONTROLS 1F – 251
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0481
HIGH SPEED COOLING FAN RELAY CIRCUIT FAULT
(1.4L DOHC)
Circuit Description
Ignition voltage is supplied directly to the cooling fan relay
coil. The engine control module(ECM) controls the relay
by grounding the control circuit via an internal switch called
a driver. The primary function of the driver is supply the
ground for the component being controlled. Each driver
has a fault line which is monitored by the ECM. When the
ECM is commanding a component ON, the voltage of the
control circuit should be low (near 0volts). When the ECM
is commanding the control circuit to a component OFF, the
voltage potential of the circuit should be high(near battery
voltage). If the fault detection circuit senses a voltage oth-
er than what is expected, the fault line status will change
causing the DTC to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the relay.
Conditions for Setting the DTC
S The high speed cooling fan control circuit is an
open or a short to battery or a short to ground con-
dition exist.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate after three consecutive trip with a fail.S The ECM will record operating conditions ant 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 10 sec-
onds.
Diagnostic Aids
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot be
duplicated, the information included in the Freeze Frame
and/or failure records data can be useful in determining
how many miles since the DTC set. The fail counter and
Pass Counter can also be used to determine how many
ignition cycles the diagnostics reported a Freeze Frame
conditions (rpm, load, vehicle speed, temperature, etc.)
that .are noted. This will isolate when the DTC failed.
DTC P0481 – High Speed Cooling Fan Relay 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 ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when command-
ed?–Go to Step 3Go to Step 5
31. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in high speed relay control circuit, at
terminal 9 to ground for 2 minutes.
Does the amperage measure less than the specified
value?0.75 ampsGo to
”Diagnostic
Aids”Go to Step 6
1F – 254IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0481
HIGH SPEED COOLING FAN RELAY CIRCUIT FAULT
(1.6L DOHC)
Circuit Description
Ignition voltage is supplied directly to the cooling fan relay
coil. The engine control module(ECM) controls the relay
by grounding the control circuit via an internal switch called
a driver. The primary function of the driver is supply the
ground for the component being controlled. Each driver
has a fault line which is monitored by the ECM. When the
ECM is commanding a component ON, the voltage of the
control circuit should be low (near 0volts). When the ECM
is commanding the control circuit to a component OFF, the
voltage potential of the circuit should be high(near battery
voltage). If the fault detection circuit senses a voltage oth-
er than what is expected, the fault line status will change
causing the DTC to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the relay.
Conditions for Setting the DTC
S The high speed cooling fan control circuit is an
open or a short to battery or a short to ground con-
dition exist.
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
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot be
duplicated, the information included in the Freeze Frame
and/or failure records data can be useful in determining
how many miles since the DTC set. The fail counter and
Pass Counter can also be used to determine how many
ignition cycles the diagnostics reported a Freeze Frame
conditions (rpm, load, vehicle speed, temperature, etc.)
that .are noted. This will isolate when the DTC failed.
DTC P0481 – High Speed Cooling Fan Relay 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 ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when command-
ed?–Go to Step 3Go to Step 5
31. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in high speed relay control circuit, at
terminal 9 to ground for 2 minutes.
Does the amperage measure less than the specified
value?0.75 ampsGo to
”Diagnostic
Aids”Go to Step 6
ENGINE CONTROLS 1F – 257
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0501
VEHICLE SPEED NO SIGNAL (M/T ONLY)
Circuit Description
Vehicle speed information is provided to the engine control
module (ECM) by the voltage speed sensor (VSS) is a per-
manent magnet generator that is mounted in the transaxle
and produces a pulsing voltage whenever vehicle speed
is over 3 mph (5km/h). The A/C voltage level and the num-
ber of pulses increase with vehicle speed. The ECM con-
verts the pulsing voltage into mph (km/h) and than sup-
plies the necessary signal to the instrument panel for
speedometer/ odometer operation and to the cruise con-
trol module and multi–function alarm module operation.
The Diagnostic Trouble Code (DTC) will detect if vehicle
speed is reasonable according to engine rpm and load.
Conditions for Setting the DTC
S Vehicle speed is not change at least 25 seconds.
S Engine speed is greater than 2,500rpm.
S MAF is greater than 180mg/tdc.
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
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.
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