Daewoo MATIZ Service Manual page 202

1F – 104 ENGINE CONTROLS
DIAGNOSTIC TROUBLE CODE (DTC) – P0141 HEATED OXYGEN SENSOR
Circuit Description
The engine control module (ECM) supplies a voltage of
about 450mm volts between the ECM terminals 44 and
13. The oxygen (O ) sensor varies the voltage within a
2
range of about 1volt if the exhaust is rich, down to about
100mm volts if the exhaust is lean. The O
an open circuit and produces no voltage when it is below
360°C(600°F). An open O
sensor causes "open loop" operation.
Conditions for Setting the DTC
D Heated oxygen sensor 5V reference voltage supply
circuit high voltage or ground.
D Heated oxygen sensor 5V reference voltage supply
circuit open.
Action Taken when the DTC Sets
D Emission related.
D "Armed" after two trip with a fail.
D "Disarmed" after one trip with a pass.
D MIL on if failure is detected in three consecutive trips.
D Stores a History DTC on the third consecutive with a
fail (The DTC will be armed after the second fail).
D Stores a Freeze Frame on the third consecutive trip
with a fail (if empty).
HEATER MALFUNCTION
sensor is like
2
sensor circuit or a cold O
2
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
2
D Normal scan tool voltage varies between 0.1volts and
0.9 volts while in closed loop.
D Inspect the oxygen (O
may be positioned incorrectly and contacting the ex-
haust manifold.
D Check for an intermittent ground in the wire between
the O sensor and the engine control module.
2
D Perform an injector 2alance test to determine if a re-
stricted fuel injector may be causing the lean condi-
tion.
D Vacuum of crankcase leaks will cause a lean running
condition.
D An exhaust manifold gasket leak of a cracked ex-
haust manifold may cause outside air to be pulled into
the exhaust and past the sensor.
MAA1F140
) sensor wire. The O sensor
2 2
DAEWOO M-150 BL2