2004 DAEWOO LACETTI Resistance vs temperature

ENGINE CONTROLS 1F – 125
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0117
ENGINE COOLANT TEMPERATURE SENSOR LOW
VOLTAGE
Circuit Description
The Engine Coolant Temperature sensor (ECT) uses a
thermistor to control the signal voltage to the engine con-
trol module (ECM).
The ECM supplies a voltage on the signal circuit to the
sensor. When the engine coolant is cold, the resistance is
high; therefore the ECT signal voltage will be high.
As the engine warms, the sensor resistance becomes
less, and the voltage drops. At normal engine operating
temperature, the voltage will be between 1.5 and 2.0 volts
at the ECT signal terminal.
The ECT sensor is used to the following items:
S Fuel delivery.
S Lock Up Clutch (LUC).
S Ignition.
S Evaporative Emission (EVAP) Canister Purge
Valve.
S Electric cooling fan.
Conditions for Setting the DTC
S ECT voltage is less than 0.03V.
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 The coolant fan turns ON.
S The ECM will default to 20°C (68°F) for the first 60
seconds of the engine run time, and then 92 °C
(198 °F).
S The scan tool will not show the 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
After the engine has started, the ECT should rise steadily
to about 90°C (194°F) then stabilize when the thermostat
opens.
Use the temperature vs. Resistance values table to evalu-
ate the possibility of a skewed sensor. Refer to ”Tempera-
ture vs. Resistance” in this section.

1F – 128IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0118
ENGINE COOLANT TEMPERATURE SENSOR HIGH
VOLTAGE
Circuit Description
The coolant temperature sensor (ECT) uses a thermistor
to control the signal voltage to the engine control module
(ECM).
he ECM supplies a voltage on the signal circuit to the sen-
sor. When the air is cold, the resistance is high; therefore
the ECT sensor signal voltage will be high.
As the engine warms, the sensor resistance becomes
less, and the voltage drops. At normal engine operating
temperature, the voltage will be between 1.5 and 2.0 volts
at the ECT sensor signal terminal.
The ECT sensor is used to the following items:
S Fuel delivery.
S Lock Up Clutch (LUC).
S Ignition.
S Evaporative Emission (EVAP) Canister Purge
Valve.
S Electric cooling fan.
Conditions for Setting the DTC
S ECT voltage is greater than 4.98V.
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 The coolant fan turns ON.
S The ECM will substitutes a fixed MAP value and
use TP to control the fuel delivery (the scan tool will
not show defaulted)
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
After the engine has started, the ECT should rise steadily
to about 90°C (194°F) then stabilize when the thermostat
opens.
Use the temperature vs. Resistance values table to evalu-
ate the possibility of a skewed sensor. Refer to ”Tempera-
ture vs. Resistance” in this section.

1F – 190IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
19Repair the open ignition feed circuit between the fuel
injector harness connector and the fuel injector con-
nector.
Is the repair complete?–Go to Step 27–
20Measure the resistance of the spark plug cable that
the spark plug tester did not spark.
Is the resistance of the spark plug cable less than the
specified value?30000WGo to Step 21Go to Step 25
21Inspect the Engine Control Module (ECM) connec-
tor and connections.
Are the connections OK?–Go to Step 22Go to Step 23
22Check the affected cylinders ignition control circuit
for an open or short and repair as necessary.
Is the repair complete?–Go to Step 27Go to Step 26
23Repair the connector or connections.
Is the repair complete?–Go to Step 27–
241. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 27–
25Replace the spark plug cable.
Is the repair complete?–Go to Step 27–
26Replace the faulty ignition coil.
Is the repair complete?–Go to Step 27Go to Step 24
271. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 28Go to Step 2
28Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK

1F – 194IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
19Repair the open ignition feed circuit between the fuel
injector harness connector and the fuel injector con-
nector.
Is the repair complete?–Go to Step 27–
20Measure the resistance of the spark plug cable that
the spark plug tester did not spark.
Is the resistance of the spark plug cable less than the
specified value?30000WGo to Step 21Go to Step 25
21Inspect the Engine Control Module (ECM) connec-
tor and connections.
Are the connections OK?–Go to Step 22Go to Step 23
22Check the affected cylinders ignition control circuit
for an open or short and repair as necessary.
Is the repair complete?–Go to Step 27Go to Step 26
23Repair the connector or connections.
Is the repair complete?–Go to Step 27–
241. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 27–
25Replace the spark plug cable.
Is the repair complete?–Go to Step 27–
26Replace the faulty ignition coil.
Is the repair complete?–Go to Step 27Go to Step 24
271. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 28Go to Step 2
28Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK

1F – 246IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
41. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Using a DVM, measure the resistance between
terminals 85 and 10 in the relay control circuit
in the ECM harness connector to ground.
Does the DVM display infinite resistance?–Go to Step 12Go to Step 10
51. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Connect a test light between the relay coil ter-
minals 86 and 85 in the relay harness connec-
tor.
4. Turn the Turn the ignition switch to ON.
5. Using the scan tool, command the relay ON
and OFF.
Does the test light turn ON and OFF with each com-
manded?–Go to Step 8Go to Step 6
6With the test light connected to ground, probe the
ignition feed circuit in the relay harness connector.
Does the test light illuminate?–Go to Step 7Go to Step 11
71. Turn the ignition switch to LOCK.
2. Reconnect the relay.
3. Disconnect the ECM connector containing the
relay control circuit.
4. Turn the Turn the ignition switch to ON.
5. With a fused jumper wire connected to ground,
probe the relay control circuit at terminal 10 in
the ECM harness connector.
Does the relay operate?–Go to Step 9Go to Step 10
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12
9Check the connection at the ECM.
Is a problem found and corrected?–Go to Step 11Go to Step 13
10Repair the faulty relay control circuit.
Is the repair complete?–Go to Step 14–
11Repair the faulty relay ignition feed circuit.
Is the repair complete?–Go to Step 14–
12Replace the relay.
Is the replacement complete?–Go to Step 14–
13Replace the ECM.
Is the replacement complete?–Go to Step 14–
141. 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 15Go to Step 2
15Check 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 – 249
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
41. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Using a DVM, measure the resistance between
terminals 85 and 10 in the relay control circuit
in the ECM harness connector to ground.
Does the DVM display infinite resistance?–Go to Step 12Go to Step 10
51. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Connect a test light between the relay coil ter-
minals 86 and 85 in the relay harness connec-
tor.
4. Turn the Turn the ignition switch to ON.
5. Using the scan tool, command the relay ON
and OFF.
Does the test light turn ON and OFF with each com-
manded?–Go to Step 8Go to Step 6
6With the test light connected to ground, probe the
ignition feed circuit in the relay harness connector.
Does the test light illuminate?–Go to Step 7Go to Step 11
71. Turn the ignition switch to LOCK.
2. Reconnect the relay.
3. Disconnect the ECM connector containing the
relay control circuit.
4. Turn the Turn the ignition switch to ON.
5. With a fused jumper wire connected to ground,
probe the relay control circuit at terminal 10 in
the ECM harness connector.
Does the relay operate?–Go to Step 9Go to Step 10
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12
9Check the connection at the ECM.
Is a problem found and corrected?–Go to Step 11Go to Step 13
10Repair the faulty relay control circuit.
Is the repair complete?–Go to Step 14–
11Repair the faulty relay ignition feed circuit.
Is the repair complete?–Go to Step 14–
12Replace the relay.
Is the replacement complete?–Go to Step 14–
13Replace the ECM.
Is the replacement complete?–Go to Step 14–
141. 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 15Go to Step 2
15Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK

1F – 252IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
41. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Using a DVM, measure the resistance between
terminals 85 and 9 in the relay control circuit in
the ECM harness connector to ground.
Does the DVM display infinite resistance?–Go to Step 12Go to Step 10
51. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Connect a test light between the relay coil ter-
minals 86 and 85 in the relay harness connec-
tor.
4. Turn the Turn the ignition switch to ON.
5. Using the scan tool, command the relay ON
and OFF.
Does the test light turn ON and OFF with each com-
manded?–Go to Step 8Go to Step 6
6With the test light connected to ground, probe the
ignition feed circuit in the relay harness connector.
Does the test light illuminate?–Go to Step 7Go to Step 11
71. Turn the ignition switch to LOCK.
2. Reconnect the relay.
3. Disconnect the ECM connector containing the
relay control circuit.
4. Turn the Turn the ignition switch to ON.
5. With a fused jumper wire connected to ground,
probe the relay control circuit at terminal 9 in
the ECM harness connector.
Does the relay operate?–Go to Step 9Go to Step 10
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12
9Check the connection at the ECM.
Is a problem found and corrected?–Go to Step 11Go to Step 13
10Repair the faulty relay control circuit.
Is the repair complete?–Go to Step 14–
11Repair the faulty relay ignition feed circuit.
Is the repair complete?–Go to Step 14–
12Replace the relay.
Is the replacement complete?–Go to Step 14–
13Replace the ECM.
Is the replacement complete?–Go to Step 14–
141. 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 15Go to Step 2
15Check 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 – 271
DAEWOO V–121 BL4
DTC P0562 – System Voltage(Engine Side) Too Low
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”
21. Install a scan tool and clear the Diagnostic
Trouble Codes (DTCs).
2. Start the engine and raise the engine speed to
the specified value.
3. Load the electrical system by turning on the
headlights, high blower motor, etc.
Is the ignition voltage less than the specified value?1,400rpm 10VGo to Step 3Go to Step 8
31. With the engine still running at the specified
value.
2. Using a digital voltmeter(DVM), measure the
battery voltage at the battery.
Is the battery voltage greater than the specified val-
ue?1,400rpm 12VGo to Step 4Go to
”Diagnostic
Aids”
41. Turn the ignition switch to LOCK.
2. Disconnect the engine control module(ECM)
connector at the ECM.
3. Turn the Turn the ignition switch to ON with the
engine OFF.
4. Using a DVM, measure the ignition voltage at
the ignition feed circuit, terminal 29.
Is the ignition voltage greater than the specified val-
ue?10VGo to Step 5Go to Step 6
5Check for a malfunctioning connection at the ECM
harness terminals and repair as necessary.
Is a repair necessary?–Go to Step 8Go to Step 7
6Repair the poor connection (high resistance) in the
ignition feed circuit.
Is the repair complete?–Go to Step 8–
7Replace the ECM.
Is the replacement complete?–Go to Step 8–
81. Using the scan tool, clear the 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 9Go to Step 2
9Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK