Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Oxygen sensor circuit no activity
detected / Circuit description
Toyota Corolla (E120): Circuit description
Refer to dtc p0130
Dtc no. |
Dtc detecting condition |
Trouble area |
P0134 | After engine is warmed up, heated oxygen sensor (bank 1
sensor 1) output does not indicate rich (greater than 0.45 V)
even once when conditions (a), (b), (c), (d) and (e) continue for
more than 65 seconds (1 trip detection logic) :
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Hint
: after confirming dtc p0134, check the output voltage of the heated oxygen sensor (bank 1 sensor 1) in the ”diagnosis / enhanced obd ii / data list / all” using the hand-held tester or the obd ii scan tool.
If the output voltage of the heated oxygen sensor is always less than 0.1 V, the sensor circuit may be open or short.
Monitor description
The ecm uses the heated oxygen sensor to optimize the air–fuel mixture in the closed–loop fuel control.
This control helps decrease exhaust emissions by providing the catalyst with a nearly stoichiometric mixture.
The sensor detects the oxygen level in the exhaust gas and the ecm uses this data to control the air–fuel ratio. The sensor output voltage ranges from 0 v to 1 v. If the signal voltage is less than 0.4 V, the air–fuel ratio is lean. If the signal voltage is more than 0.5 V, the air–fuel ratio is rich. If the sensor does not indicate rich even once despite the conditions for the closed–loop fuel control being met and a specified time period has passed, the ecm will conclude that the closed–loop fuel control is malfunctioning. The ecm will illuminate the mil and a dtc is set.
Monitor strategy
Typical enabling condition
Typical malfunction thresholds
Component operating range
Wiring diagram
Refer to dtc p0130
Other materials:
Inspection procedure
Hint:
hand–held tester only:
narrowing down the trouble area is possible by performing ”a/f control” active
test (heated oxygen
sensor or other trouble areas can be distinguished).
Perform active test using hand–held tester (a/f control).
Hint:
”a/f control” is the active te ...
Problem symptoms table
Hint:
proceed with troubleshooting of each circuit in the table below.
Symptom
Suspect area
When the ignition switch is in the on position, the srs warning
light sometimes comes on after approximately 6 seconds.
Srs warning light ci ...
Inspection procedure
Hint
Advanced timing over
(valve timing is out of specified range)
P0011
Retarded timing over
(valve timing is out of specified range)
P0012
If dtc p0011 or p0012 is displayed, check the vvt system circuit.
Read freeze frame data using the hand–held tester o ...