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Daewoo Matiz (2003 year). Manual - part 43

1F – 82 ENGINE CONTROLS

DTC P0123 – Throttle Position Sensor High Voltage (Cont’d)

Step

Action

Value(s)

Yes

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 – 83

BLANK

1F – 84 ENGINE CONTROLS

MAA1F130

DIAGNOSTIC TROUBLE CODE (DTC) – P0131 OXYGEN SENSOR LOW

VOLTAGE

Circuit Description

The engine control module (ECM) supplies a voltage of
about 450m volts between the ECM terminals 44 and
13. The oxygen (O

) sensor varies the voltage within a

range of about 1volt if the exhaust is rich, down to about
100mm volts if the exhaust is lean. The O

sensor is like

an open circuit and produces no voltage when it is below
350

C(600

F). An open O

sensor circuit or a cold O

sensor causes “open loop” operation.

Conditions for Setting the DTC

(Case A)

The engine controls system is in closed loop.

Engine speed is less than 6,000rpm.

The oxygen sensor voltage is below 0.07V for at least
40seconds.

DTCs P0107, P0108, P0117, P0118, P0122, P0123,
P0335, P0336, P0341, P0342, P0400, P0404,
P0405, P0406, P0445, P0444 are NOT SET.

(Case B)

The engine controls system is in closed loop.

Engine speed is less than 6,000rpm.

The oxygen sensor voltage is between 0.352 and
0.499 at least 10seconds.

Action Taken when the DTC Sets

The Malfunction Indicator Lamp (MIL) will illuminate.

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.

A history DTC is stored.

Conditions for Clearing the MIL/DTC

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

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

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

Disconnecting the ECM battery feed for more than 10
seconds.

Diagnostic Aids

Normal scan tool voltage varies between 0.1volts and
0.9 volts while in closed loop.

Inspect the oxygen (O

) sensor wire. The O

sensor

may be positioned incorrectly and contacting the ex-
haust manifold.

Check for an intermittent ground in the wire between the
O

sensor and the engine control module.

Perform an injector 2alance test to determine if a re-
stricted fuel injector may be causing the lean condition.

Vacuum of crankcase leaks will cause a lean running
condition.

An exhaust manifold gasket leak of a cracked exhaust
manifold may cause outside air to be pulled into the ex-
haust and past the sensor.

ENGINE CONTROLS 1F – 85

DTC P0131 – Oxygen Sensor Low Voltage

Step

Action

Value(s)

Yes

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”

1. Connect the scan tool to the data link

connector(DLC).

2. Run the engine until it reaches operating

temperature.

3. Check for closed loop operation.
Does the engine control module(ECM) go into
closed loop?

–

Go to Step 3

Go to Step 9

1. Run the until until it reaches operating

temperature?

2. Run the engine at 1,200rpm.
Does the scan tool read the upstream oxygen(O

)

sensor signal voltage between the valve specified?

0.15~0.7V

Go to Step 5

Go to Step 4

Does the scan tool read the Oxygen sensor signal
voltage fixed below the valve specified?

0.01V

Go to Step 7

Go To

“Diagnostic

Aids”

1. Disconnect the Oxygen sensor connector.
2. Run the warm engine at idle.
Does the scan tool read the Oxygen sensor signal
voltage between the valve specified?

0.15~0.7V

Go To

“Diagnostic

Aids”

Go to Step 6

1. Turn the ignition switch to LOCK.
2. Check the Oxygen sensor wire between the

Oxygen sensor and the ECM connector terminal
77 and 13 is open.

Is the problem found?

–

Go to Step 8

Go to Step 11

1. Turn the ignition switch to LOCK.
2. Check the Oxygen sensor wire between the
Oxygen sensor and the ECM connector terminal 77
for a short to ground.
Is the problem found?

–

Go to Step 8

Go to Step 11

1. Repair the wire or the connector terminal as

needed.

2. Clear the any DTCs from the ECM.
3. Road tests the vehicle.
4. Perform the diagnostic system check.
Is the repair complete?

–

System OK

–

1. Turn the ignition switch to LOCK.
2. Disconnect the Oxygen sensor connector.
3. Turn the ignition switch to ON.
Does the scan tool the Oxygen sensor signal voltage
between the valve specified?

0.15~0.7V

Go to Step 11

Go to Step 10

1. Replace the Oxygen sensor.
2. Clear the DTCs from the ECM.
3. Perform the diagnostic system check.
Is the repair complete?

–

System OK

–

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

–

Go to Step 12

–

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