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:
Diagnostic trouble code chart
Hint:
as for the vehicle for mexico, refer to repair manual 2003 corolla (pub. No.
Rm938u).
Parameters listed in the chart may not be exactly the same as your readings due
to the type of instrument
or other factors.
If a malfunction code is displayed during the dtc check in the check mod ...
Communication system
Horn system
Location
Problem symptoms table
Inspection
1. Inspect low pitched horn assy
Connect the positive (+) lead from the battery to the terminal
and the negative (–) lead to the horn body, and check
that the horn blows.
If the result is not as specified, replace the ...
Antenna cord sub–assy
Replacement
Hint: components:
1. Remove instrument panel sub–assy upper
Hint:
refer to the procedure until the step, ”remove instrument panel sub–assy
upper” of
instrument panel sub–assy lower.
Remove the related parts as long as the antenna cord sub–assy can be
removed ...


