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 ...
Inspection procedure
Hand–held tester:
1 Perform active test by hand–held tester(operation of circuit
opening relay)
Connect the hand–held tester to the dlc3.
turn the ignition switch on and push the hand–held tester main
switch on.
select the item ”diagnosis / enhanced obd ii / active ...
Circuit description
The ignition switch provides circuit power and the ecm provides the circuit
ground that illuminates the mil.
Mil operation is checked visually:
it should be illuminated when the ignition is first turned on. If the mil is off
all of the time or on all of the time,
use the procedure below to ...


