Daewoo MATIZ Service Manual page 198

1F – 100 ENGINE CONTROLS
DIAGNOSTIC TROUBLE CODE (DTC) – P0140 HEATED OXYGEN SENSOR NO
Circuit Description
The engine control module (ECM) supplies a voltage of
about 450mm volts between the ECM terminals 64 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 The engine controls system is in closed loop.
D Engine Coolant Temperature is higher than 70°C
(140°F).
D The mass air flow(MAF) is between 25kg/h and
50kg/h.
D The engine speed is between 2,400rpm and 300rpm.
D The vehicle speed is between 64km/h(12.4mph) and
80km/h(24.9mph).
D The manifold air pressure is higher than 70kPa.
D The ignition is at 10 volts.
D No transition from rich side to lean side or lean side to
rich side during 7.8 seconds even with a forcing of O
sensor controller.
D DTCs P0107, P0108, P0112, P0113, P0117, P0118,
P0122, P0123, P0137, P0138, P0137, P0138,
ACTIVITY
sensor is like
2
sensor circuit or a cold O
2
P0137, P0138, P1671, P0300, P0335, P0336,
P0341, P0400, P0404, P0405, P0644, P0645 are
NOT SET.
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.
2
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).
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 10 seconds.
Diagnostic Aids
2
D Normal scan tool voltage varies between 0.15 to
8.5mV while in Closed Loop. If DTC P0140 is inter-
mittent, refer to "Intermittent" in this Section.
MAA1F140
DAEWOO M-150 BL2