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:
Interior
SRS airbags
Floor mats
Front seats
Head restraints
Seat belts
Console box
Inside lock buttons
Cup holders
Rear seats
Rear seat heater switches*
*: If equipped
■Ceiling
Inside rear view mirror
Sun visors
Vanity mirrors
Vanity lights*
Interior lights/personal lights
Moon roof sw ...
Front passenger occupant classification system
Your vehicle is equipped with a front passenger occupant classification system.
This system detects the conditions of the front passenger seat and activates or
deactivates the devices for the front passenger.
1 SRS warning light
2 Seat belt reminder light
3 “AIR BAG OFF” indicator light ...
Calculation formula for your vehicle
1 Cargo capacity
2 Total load capacity (vehicle capacity weight)
When 2 people with the combined weight of A lb. (kg) are riding in your vehicle,
which has a total load capacity (vehicle capacity weight) of B lb. (kg), the available
amount of cargo and luggage load capacity will be C lb. (kg ...


