Toyota Celica 2005 Repair Manual page 1269

DI−1068
Stop Light Switch Circuit
CIRCUIT DESCRIPTION
When the brake pedal is depressed, the stop light switch sends a signal to ECU. When ECU receives this
signal, it cancels the cruise control.
A fail−safe function is provided so that the cruise control is canceled normally when there is a malfunction
in the stop light signal circuit.
The cancellation occurs when the battery positive voltage is applied to terminal STP−.
When the brake is ON, battery positive voltage is applied to terminal STP− of the ECU via the stop fuse and
the stop light switch, and then the ECU turns the cruise control OFF.
Even if the harness connected to terminal STP− has an open circuit, the cruise control will be turned OFF.
Also, when the brake is ON, the magnetic clutch circuit is cut mechanically by the stop light switch, turning
the cruise control OFF (See page DI−1052 for operation of the magnetic clutch).
2005 CELICA (RM1131U)
DIAGNOSTICS − CRUISE CONTROL SYSTEM (1ZZ−FE)
1268
DI08T−36