Toyota Corolla Repair Manual: Inspection procedure
Hint
:
- if different dtcs related to different systems that have terminal e2
as the ground terminal are output
simultaneously, terminal e2 may be open.
- Read freeze frame data using the hand-held tester or the obd ii scan
tool. Freeze frame data records
the engine conditions when a malfunction is detected. When troubleshooting,
it is useful for determining
whether the vehicle was running or stopped, the engine was warmed up or not,
the air–fuel ratio
was lean or rich, etc. At the time of the malfunction.
Hand–held tester:
1 Read value of hand–held tester(throttle valve opening
percentage)

- Connect the hand–held tester to the dlc3.
- turn the ignition switch on.
- select the item ”diagnosis / enhanced obd ii /
data list / etcs / throttle pos” and read its value
displayed on the hand–held tester.
Result:



2 Inspect throttle position sensor

- Disconnect the t1 throttle position sensor connector.
- measure the resistance between the terminals of the
throttle position sensor.
Standard

- Reconnect the throttle position sensor connector.


3 Check harness and connector(ecm – throttle position sensor)

- Disconnect the e3 ecm connector.
- measure the resistance between the terminals of the e3
ecm connector.
Standard:

- Check the resistance between the terminals of the e3
ecm connector.
Standard (check for short):

- Reconnect the ecm connector.


Replace ecm
4 Inspect throttle position sensor

- Disconnect the t1 throttle position sensor connector.
- measure the resistance between the terminals of the
throttle position sensor.
Standard:

- Reconnect the throttle position sensor connector.


5 Check harness and connector(ecm – throttle position sensor)

- Disconnect the e3 ecm connector.
- disconnect the t1 throttle position sensor connector.
- check the resistance between the wire harness side connectors.
Standard (check for open):

Standard (check for short):

- Reconnect the throttle position sensor connector.
- reconnect the ecm connector.



Replace ecm
Obd ii scan tool (excluding hand–held tester):
1 Inspect throttle position sensor

- Disconnect the t1 throttle position sensor connector.
- measure the resistance between the terminals of the
throttle position sensor.
Standard:

- Reconnect the throttle position sensor connector.


2 Check harness and connector(throttle position sensor – ecm)

- Disconnect the e3 ecm connector.
- measure the resistance between the terminals of the e3
ecm connector.
Standard:

- Check the resistance between the terminals of the e3
ecm connector.
Standard (check for short):

- Reconnect the ecm connector.


The throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately
0.3 To 1.0 V is ...
Dtc p0121 throttle/pedal position
sensor/switch ”a” circuit
range/performance problem
Hint:
this is the purpose of the ”throttle position sensor”. ...
Other materials:
How to use this manual
General information
1. General description
This manual is made in accordance with sae j2008.
generally, repair operations can be separated in the following 3
main processes:
Diagnosis
Removing/installing, replacing, disassembling/reassembling,
checking and adju ...
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 test which cha ...
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 ...