Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Oxygen sensor heater control
circuit... / Inspection procedure
Toyota Corolla (E120): 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.
1 Inspect heated oxygen sensor(heater resistance)
- Disconnect the h5 or h8 heated oxygen sensor connector.
- measure the resistance between the terminals of the heated oxygen sensor connector.

Standard:

- Reconnect the heated oxygen sensor connector.


2 Inspect efi relay
- Remove the efi relay from the engine room r/b.
- check for continuity in the efi relay.

Standard:

- Reinstall the efi relay.


3 Inspect ecm(ht1a or ht1b voltage)
- Turn the ignition switch on.
- measure the voltage between the applicable terminals of the e4 and e5 ecm connectors.

Standard:



4 Check harness and connector(heated oxygen sensor – ecm, heated oxygen sensor – efi relay)
- Check the harness and connector between the ecm and heated oxygen sensor connectors.
- Disconnect the h5 or h8 heated oxygen sensor connector.
- Disconnect the e4 or e5 ecm connector.
- Check the resistance between the wire harness side connectors.

Standard (check for open):

Standard (check for short):


- Reconnect the heated oxygen sensor connector.
- Reconnect the ecm connector.
- check the harness and connector between the heated oxygen sensor connector and efi relay.
- Disconnect the h5 or h8 heated oxygen sensor connector.
- Remove the efi relay from the engine room r/b.
- Check the resistance between the wire harness side connectors.

Standard (check for open):

Standard (check for short):

- Reconnect the heated oxygen sensor connector.
- Reinstall the efi relay.


Replace ecm
Other materials:
Adjustment
1. Inspect park/neutral position switch assy
apply the parking brake and turn the ignition switch on.
depress the brake pedal and check that the engine starts only when
the shift lever is set in n or p position
and it does not start in the other position.
check that th ...
Inspection procedure
1 Check voltage at ig2 of airbag sensor assy center
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connector of the airbag sensor assy center.
connect the negative (–) terminal cable to the battery,
and wa ...
Maintenance data (fuel, oil level,
etc.)
Dimensions and weight
*1:Unladen vehicles
*2:Vehicles without 18-inch tires
*3:Vehicles with 18-inch tires for Guam and Saipan
*4:Vehicles with 18-inch tires except for Guam and Saipan
*5:For Guam and Saipan
Seating capacity
Vehicle identification
■ Vehicle identification number
The vehicle iden ...


