Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Cruise control system / Stop light switch circuit / Circuit description
Toyota Corolla (E120): Circuit description
When the brake pedal is depressed, the stop lamp switch assy sends a signal to the cruise control ecu assy.
When the cruise control ecu assy receives this signal, it cancels the cruise control.
A fail–safe function is provided so that cancel functions normally, even if there is a malfunction in the stop light switch circuit.
The cancel conditions are: battery positive voltage at terminal stp–.
When the brake pedal is depressed, normal battery positive voltage normally is applied through the stop fuse and stop lamp switch assy to terminal stp– of the cruise control ecu assy, and the cruise control ecu assy turns the cruise control to off.
If the harness connected to terminal stp– has an open circuit, terminal stp– will have battery positive voltage and the cruise control will be turned off.
Also, when the brake pedal is depressed, the magnetic clutch circuit is cut mechanically by the stop lamp switch assy, turning the cruise control off.
Wiring diagram

Other materials:
Problem symptoms table
Hint:
if a normal code is displayed during the dtc check but the trouble still occurs,
check the circuits for each
symptom in the order given in the charts on the following pages and proceed to
the page given for troubleshooting.
The matrix chart is divided into 3 chapters.
If the instruc ...
Steering wheel audio switches
Some audio features can be controlled using the switches on the steering wheel.
Operation may differ depending on the type of audio system or navigation system.
For details, refer to the manual provided with the audio system or navigation system.
Operating the audio system using the steering whe ...
On–vehicle inspection
1. Inspect cooling system for leaks
Caution:
to avoid the danger of being burned, do not remove the radiator
cap while the engine and radiator are still hot, as fluid
and steam can be blown out under pressure.
fill the radiator with coolant and attach a radiator cap tester.
  ...


