Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Toyota vehicle intrusion protection system / Ignition switch circuit / Circuit description
Toyota Corolla (E120): Circuit description
If the ignition switch is turned to the on position, battery positive voltage is applied to the switches, such as terminal ig of the ecu.
Wiring diagram

Other materials:
Circuit description
The fuel trim is related to the feedback compensation value, not to the basic
injection time. The fuel trim includes
the short–term fuel trim and the long–term fuel trim.
The short–term fuel trim is the short–term fuel compensation used to maintain
the air–fuel ratio at stoichiomet ...
Components
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Monitor description
The battery supplies electricity to the ecm even when the ignition switch is
off. This electricity allows the
ecm store data such as dtc history, freeze frame data, fuel trim values, and
other data. If the battery voltage
falls below a minimum level, the ecm will conclude that there is a fault ...


