TSRM/MK4 Supra/Repair Manual
Repair ManualWiring Diagrams
p.181
BE/Body Electrical Systems182 / 203
p.183
Stop Light Switch Circuit — MK4 Supra Body Electrical Systems, page 182
100%
BE–182 BODY ELECTRICAL SYSTEM – CRUISE CONTROL SYSTEM Stop Light Switch Circuit CIRCUIT DESCRIPTION When the brake is on, battery voltage normally applies through the stop fuse and stop switch to terminal STP–of the ECU, and the ECU turns the cruise control off. A fail–safe function is provided so that cancel functions normally, even if there is a malfunction in the stop light signal circuit. (1) If the harness connected to terminal STP–has an open, terminal STP–will have battery positive voltage and the cruise control will be turned off, also SET not occurring. (2) If the stop fuse is open, terminal STP + becomes approx. 0 V when the brake is turned on, so the ECU performs cancel function normally. Also, when the brake is on, the magnetic clutch is cut mechanically by the stop light switch, turning the cruise control off. (See page BE–173 for operation of the magnetic clutch.) WIRING DIAGRAM Cruise Control ECU BR-B L- 26 12V BR-B W STP+ 1 12V Stop Light Switch 2 1 STP- 17 IB6 8 R-L 4 3 B-W 16 R-L IB6 L G-W 10 5 1H BR-B 10 1C 4 7 G-W R-W R-W 2 Light 3 3 Failure Sensor LH RH 5 W-B Stop Light 5 W-B NG8439