Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Mass or volume air flow circuit
range/performance problem / Circuit description
Toyota Corolla (E120): Circuit description
Refer to dtcs p0100
Dtc no. |
Dtc detection condition | Trouble area |
P0101 | After engine is warmed up, conditions (a) to (d) continue for
more than 10 seconds (2 trip detection logic):
|
|
Conditions (a) and (b) continue for more than 6 seconds: (2 trip
detection logic)
|
Monitor description
The maf (mass air flow) sensor helps the ecm calculates the amount of air flowing through the throttle valve. The ecm uses this information to determine the fuel injection time and provides a proper air–fuel ratio.
Inside the maf sensor, there is a heated platinum wire exposed to the flow of intake air. By applying a specific current to the wire, the ecm heats this wire to a given temperature. The flow of incoming air cools the wire and an internal thermister, changing their resistance. To maintain a constant current value, the ecm varies the voltage applied to these components in the maf sensor. The voltage level is proportional to the air flow through the sensor and the ecm interprets this voltage as the intake air amount. If there is a defect in the sensor or an open or short circuit, the voltage level will deviate outside the normal operating range. The ecm interprets this deviation as a defect in the maf sensor and sets a dtc.
Example: if the voltage is more than 2.2 V at idle, or less than 0.4 V at idle off, the ecm interprets this as a defect in the maf sensor and sets a dtc.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Wiring diagram
Refer to dtc p0100
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).
Perform active test using the hand–held ...
Inspection procedure
1 Check side air bag sensor assy rh
Sst 09843–18040
Connect the negative (–) terminal cable to the battery,
and wait at least for 2 seconds.
turn the ignition switch to on, and wait at least for 20 seconds.
clear the dtc stored in memory .
turn the ignition swi ...
How to proceed with troubleshooting
Troubleshoot in accordance with the procedure on the following pages.
1 Vehicle brought to workshop
2 Customer problem analysis check and symptom check
Without applicable symptoms, proceed to ”a”.
with applicable symptoms, proceed to ”b”.
3 Symptom simulation
4 Prob ...