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 p/t squib(rh) circuit(airbag sensor assy center – front
seat outer belt assy rh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the seat belt pretensio ...
If your vehicle overheats
The following may indicate
that your vehicle is overheating.
The engine coolant temperature
gauge is in the red zone or a loss
of engine power is experienced.
(For example, the
vehicle speed does not
increase.)
"Engine Coolant Temp High
Stop in a Safe Place See
Owner's Manual" is shown
on ...
Circuit description
A flat type knock sensor (non–resonant type) has the structure that can
detect the vibration in a wider band
of frequency from about 6 khz to 15 khz and has the following features.
Knock sensors are fitted on the cylinder block to detect the engine knocking.
The sensor contains a piezoele ...


