Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Stop light switch circuit / Circuit description
Toyota Corolla (E120): Circuit description
This signal is used to detect that the brakes have been applied. The stp signal voltage is the same as the one supplied to the stop lights.
The stp signal is used mainly to control the fuel cut–off engine speed (the fuel cut–off engine speed is reduced slightly when the vehicle is braking.).
Wiring diagram

Other materials:
Inspection procedure
1 Check side squib(rh) circuit(airbag sensor assy center – front
seat airbag assy rh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the front seat airbag
assy (rh) and the airbag sensor assy center. ...
Inspection procedure
1 Inspect dlc3 terminal voltage
Turn the ignition switch to on.
measure voltage between terminals 13 (tc) and 4 (cg) of
dlc3.
Ok:
voltage: 10 – 16 v
2 Check harness and connector(between cruise control ecu assy
and dlc3)
Check for open and short circuit in harness ...
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 ...


