Toyota Corolla (E120): Circuit description

Hint:

Hint

: there is a case that hand–held tester cannot be used when ecu is abnormal.

Wiring diagram

Inspection procedure

    Share this page:

    Other materials:

    System description
    The ecm uses the signals from the throttle position sensor, air–flow meter and crankshaft position sensor to monitor the engagement condition of the lock–up clutch. Then the ecm compares the engagement condition of the lock–up clutch with the lock–up schedule in the ecm memory to de ...

    Circuit description
    When the ignition switch is turned on, battery positive voltage is applied to the coilwhich closes the contacts of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm. This signal causes current to flow to the coil, closing the contacts of the efi relay and supplyin ...

    Circuit description
    If the engine coolant temperature (ect) does not reach 75°c (167°f) despite sufficient warm – up time has elapsed. Dtc no Dtc detection condition Trouble area P0128 Condition (a), (b) and (c):  cold start  after engine is warmed up & ...