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)

  1. Disconnect the h5 or h8 heated oxygen sensor connector.
  2.  measure the resistance between the terminals of the heated oxygen sensor connector.

Standard:

Standard:

  1. Reconnect the heated oxygen sensor connector.

2 Inspect efi relay

2 Inspect efi relay

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

Standard:

Standard:

  1. Reinstall the efi relay.

3 Inspect ecm(ht1a or ht1b voltage)

3 Inspect ecm(ht1a or ht1b voltage)

  1. Turn the ignition switch on.
  2.  measure the voltage between the applicable terminals of the e4 and e5 ecm connectors.

Standard:

Standard:

4 Check harness and connector(heated oxygen sensor – ecm,

4 Check harness and connector(heated oxygen sensor – ecm, heated oxygen sensor – efi relay)

  1. Check the harness and connector between the ecm and heated oxygen sensor connectors.
  1.  Disconnect the h5 or h8 heated oxygen sensor connector.
  2.  Disconnect the e4 or e5 ecm connector.
  3.  Check the resistance between the wire harness side connectors.

Standard (check for open):

Standard (check for open):

Standard (check for short):

Standard (check for short):

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

Standard (check for open):

Standard (check for open):

Standard (check for short):

Standard (check for short):

  1. Reconnect the heated oxygen sensor connector.
  2.  Reinstall the efi relay.

Replace ecm

Replace ecm

    Share this page:

    Other materials:

    Circuit description
    The srs warning light is located on the combination meter. When the srs is normal, the srs warning light lights up for approx. 6 Seconds after the ignition switch is turned from the lock position to on position, and then turns off automatically. If there is a malfunction in the srs, the srs ...

    Wiring diagram
    1 Inspect terminal voltage(pi) (a) turn Turn the ignition switch to on.  measure voltage between terminal 5 (pi) of cruise control ecu assy and body ground, when the cruise control main switch button is on and off. Ok: 2 Inspect combination meter assy 3 Check harn ...

    Circuit description
    When driving uphill under cruise control, in order to reduce the number of shifting due to on–off overdrive operation and to provide smooth driving, when down shifting in the electronically controlled transmission occurs, a signal to prevent upshift until the end of the uphill slope is sent ...