Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Toyota vehicle intrusion protection system / Horn relay circuit / Circuit description
Toyota Corolla (E120): Circuit description
When the tvip system is transferred from the armed state to the alarm sounding state, the tvip ecu switches on the horn relay so that it can sound the horns. The horn sounds in 0.4 Seconds interval.
Wiring diagram

Other materials:
Circuit description
In the diagram below, when the engine is cranked, current flows from terminal
st2 of the ignition switch to
the starter relay coil and also current flows to terminal sta of the ecm (sta
signal).
When the sta signal and ne signal are input to the ecm, tr is turned on, current
flows to the c ...
Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the
table below. Use this table to
troubleshoot the problem when a normal code is displayed in the diagnostic
trouble code chart but the problem
is still occurring. Numbers in the table indicate the order in which the
circ ...
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 ...


