Daewoo Matiz (2003 year). Manual - part 41

1F – 74  ENGINE CONTROLS

MAA1F110

DIAGNOSTIC TROUBLE CODE (DTC) – P0118 ENGINE COOLANT

TEMPERATURE SENSOR HIGH VOLTAGE

Circuit Description

The coolant temperature sensor (ECT) uses a thermis-
tor to control the signal voltage to the engine control
module (ECM).

The ECM supplies a voltage on the signal circuit to the
sensor. 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:

D

Fuel delivery.

D

Lock Up Clutch (LUC).

D

Ignition.

D

Evaporator Emission (EVAP) Canister Purge Valve.

D

Idle Air Control (IAC) valve.

D

Electric cooling fan.

Conditions for Setting the DTC

D

This DTC can be stored in “key-on” status.

D

The engine rum time is greater than 3 seconds.

D

The ECT sensor indicates that the engine coolant
temperature is less than –40

°

C(–40

°

F).

D

ECT voltage is greater than 4.98V.

D

A low voltage condition exits.

Action Taken when the DTC Sets

D

The Malfunction Indicator Lamp (MIL) will illuminate.

D

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.

D

A history DTC is stored.

D

The coolant fan turns ON.

D

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

D

The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.

D

A history DTC will clear after 40 consecutive warm-up
cycles without a fault.

D

DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

After the engine has started, the ECT should rise steadi-
ly to about 90

°

C(194

°

F) then stabilize when the thermo-

stat opens.

Use the temperature vs. resistance values table to eval-
uate the possibility of a skewed sensor. Refer to “Tem-
perature vs. Resistance” in this Section.

ENGINE CONTROLS  1F – 75

DTC P0118 – Engine Coolant Temperature Sensor High Voltage

Step

Action

Value(s)

Yes

No

1

Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Is the system check complete?

–

Go to Step 2

Go to

“On-Board
Diagnostic

System Check”

2

1. Connect the scan tool to the data link connector

(DLC).

2. Run the engine until it reaches operating

temperature.

Does the scan tool show the ECT sensor reading
within the value specified?

80~110

°

C

(176~230

°

F)

Go to

“Diagnostic

Aids”

Go to Step 3

3

1. Turn the ignition switch to LOCK.
2. Disconnect the ECT sensor connector.
3. Turn the ignition switch to ON.
Does the scan tool show the ECT sensor reading
within the value specified?

≥

-30

°

C

Go to Step 4

Go to Step 6

4

1. Jumper the ECT sensor signal circuits at terminal

B and A.

2. Turn the ignition switch to ON.
Does the scan tool show the ECT sensor reading
within the value specified?

≥

180

°

C

(356

°

F)

Go to Step 5

Go to Step 6

5

1. Replace the ECT sensor.
2. Clear any DTCs from the ECM.
3. Perform the diagnostic system check.
Is the replacement complete?

–

System OK

–

6

Measure the voltage between ECT terminal B and
ground.
Does the voltage measure within the value
specified?

4.5–5.0V

Go to Step 7

Go to Step 8

7

1. Turn the ignition switch to LOCK.
2. Disconnect the ECM wiring connector.
3. Check for a faulty connector or terminals at the

ECT sensor connector terminal A and the ECM
connector terminal 45 for an open or short to
battery voltage.

Is the problem found?

–

Go to Step 8

Go to Step 9

8

1. Turn the ignition switch to LOCK.
2. Repair the wire of the connector terminals as

needed.

3. Clear any DTCs from the ECM.
4. Run the engine until it reaches operating

temperature.

5. Perform the diagnostic system check.
Is the repair complete?

–

System OK

–

9

1. Replace the ECM.
2. Run the engine until it reaches operating

temperature.

3. Perform the diagnostic system check.
Is the repair complete?

–

Go to Step 10

–

10

Check if any additional DTCs are set.
Are any DTCs displaced that have not been
diagnosed?

–

Go to

applicable DTC

table

System OK

1F – 76  ENGINE CONTROLS

MAA1F120

DIAGNOSTIC TROUBLE CODE (DTC) P0122

THROTTLE POSITION SENSOR LOW VOLTAGE

Circuit Description

The Engine Control Module (ECM) supplies a 5 volt ref-
erence voltage signal and a ground to the Throttle Posi-
tion (TP) sensor. The TP sensor sends a voltage signal
back to the ECM relative to the throttle plate opening.
The voltage signal will vary from approximately 0.33
volts at closed throttle, to over 4.3 volts at Wide Open
Throttle (WOT).

The TP signal is used by the ECM for fuel control and for
most of the ECM controlled outputs. The TP signal is
one of the most important inputs used by the ECM for
fuel control and most of the ECM controlled outputs.

Conditions for Setting the DTC

D

TP sensor voltage indicates a throttle voltage less
than 0.14 volts.

Action Taken When the DTC Sets

D

The Malfunction Indicator Lamp (MIL) will illuminate.

D

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.

D

A history DTC is stored.

D

The TP angle will default to 0% when the vehicle
speed is less than 3 km/h (2 mph) and 10% when the
vehicle speed is greater than 3 km/h (2 mph). The
scan tool will not display the default value.

Conditions for Clearing the MIL/DTC

D

The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.

D

A history DTC will clear after 40 consecutive warm-up
cycles without a fault.

D

DTC(s) can be cleared by using the scan tool.

D

Disconnecting the ECM battery feed for more than 10
seconds.

Diagnostic Aids

If the DTC P0122 cannot be duplicated, the information
included in the Freeze Frame data can be useful. Use a
scan tool information data to determine the status of the
DTC. If the dc occurs intermittently, using the Diagnostic
table may help isolate the problem.

ENGINE CONTROLS  1F – 77

DTC P0122 – Throttle Position Sensor Low Voltage

Step

Action

Value(s)

Yes

No

1

Perform an On-Board Diagnostic (EOBD) System
Check.
Was the check performed?

–

Go to Step 2

Go to

“On-Board
Diagnostic

System Check”

2

1. Install a scan tool to the Data Link Connector

(DLC).

2. Turn the ignition ON.
Is the Throttle Position (TP) sensor voltage below
the specified value?

0.20 V

Go to Step 4

Go to Step 3

3

1. Turn the ignition ON.
2. Review the Freeze Frame data and note the

parameters.

3. Operate the vehicle within the Freeze Frame

conditions and Conditions for Setting the DTC as
noted.

Is the TP sensor voltage below the specified value?

0.20 V

Go to Step 4

Go to Step 12

4

1. Turn the ignition OFF.
2. Disconnect the TP sensor connector.
3. Turn the ignition ON.
4. Jump the 5 volt reference circuit terminal B and

the TP signal circuit terminal C at the TP sensor
connector.

Is the TP sensor voltage over the specified value?

4.0 V

Go to Step 10

Go to Step 5

5

Connect a test light between B+ and the TP sensor
signal circuit terminal C.
Is the TP sensor voltage greater than  the specified
value?

4.0 V

Go to Step 6

Go to Step 8

6

Check the TP sensor 5 volt reference circuit for an
open or short to ground and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 7

7

Check the 5 volt reference circuit for a poor
connection at terminal 75 of the Engine Control
Module (ECM) and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 11

8

Check the TP sensor signal circuit between terminal
C of the TP sensor and terminal 44 of the ECM for
an open or a short to ground and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 9

9

Check the TP sensor signal circuit, terminal 44 of
the ECM for a poor connection and repair as
needed.
Is the repair complete?

–

Go to Step 12

Go to Step 11

10

Replace the throttle body assembly.
Is the action complete?

–

Go to Step 12

–

11

1. Turn the ignition switch OFF.
2. Replace the ECM.
Is the action complete?

–

Go to Step 12

–