Daewoo Matiz (2003 year). Manual - part 42

1F – 78  ENGINE CONTROLS

DTC P0122 – Throttle Position Sensor Low Voltage (Cont’d)

Step

Action

Value(s)

Yes

No

12

1. 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 13

Go to Step 2

13

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

–

Go to

Applicable DTC

Table

System OK

ENGINE CONTROLS  1F – 79

BLANK

1F – 80  ENGINE CONTROLS

MAA1F120

DIAGNOSTIC TROUBLE CODE (DTC) P0123

THROTTLE POSITION SENSOR HIGH 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 greater
than 4.9 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 P0123 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.

With ignition ON and the throttle at closed position, the
voltage should read between 0.2 and 0.90 volts and in-
crease steadily to over 4.3 volts at WOT.

DTCs P0123 and P0113 stored at the same time could
be result of an open sensor ground circuit.

ENGINE CONTROLS  1F – 81

DTC P0123 – Throttle Position Sensor High 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 greater
than the specified value?

1.0 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 greater than the specified
value?

3.9 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.
Is the TP sensor voltage less than the specified
value?

0.2 V

Go to Step 5

Go to Step 6

5

Probe the TP sensor ground circuit, terminal A at the
TP sensor connector with a test light connected to
B+.
Does the test light illuminate?

–

Go to Step 7

Go to Step 9

6

Check the TP sensor signal circuit for an short to
voltage and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 11

7

Check the 5 volt reference circuit for a short to B+
and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 8

8

Check the TP sensor electric connector for a poor
connection and repair as needed.
Is the repair complete?

–

Go to Step 12

Go to Step 10

9

Check the TP sensor ground circuit for an open 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 Engine Control Module (ECM).
Is the action complete?

–

Go to Step 12

–

12

1. 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 13

Go to Step 2