Daewoo Matiz (2003 year). Manual — part 40

1F – 70 ENGINE CONTROLS

DTC P0113 – Intake Air Temperature Sensor High Voltage (Cont’d)

Step

Action

Value(s)

Yes

No

11

1. Replace the ECM
2. Perform the diagnostic system check.
Is the repair complete?

–

Go to Step 12

–

12

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

–

Go to applicable

DTC table

System OK

ENGINE CONTROLS 1F – 71

BLANK

1F – 72 ENGINE CONTROLS

MAA1F110

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
control 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:

D

Fuel delivery.

D

Lock Up Clutch (LUC).

D

Ignition.

D

Evaporator Emission (EVAP) Canister Purge 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

A low voltage condition exits.

D

ECT voltage is less than 0.03V.

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 default to 20

°

C(68

°

F)for the first 60

seconds of the engine run time, and then
92

°

C(198

°

F).

D

the scan ttol will not show the defaulted 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.

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 – 73

DTC P0117 – Engine Coolant Temperature Sensor Low 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 IAT sensor reading
within the value specified?

≥

-30

°

C(-22

°

F)

Go to Step 4

Go to Step 6

4

1. Jumper the ECT sensor signal circuits at terminal

A and B.

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

≥

120

°

C

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 A 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 connectors and ECM connectors for
short to ECM reference voltage.

Is the problem found?

–

Go to Step 9

Go to Step 8

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