Wiring Diagrams
WARNING: This page is about a different car, the 2002 Lexus GS 430 and 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
For GS 300 cruise control wiring diagram, see appropriate CRUISE CONTROL in SYSTEM WIRING DIAGRAMS article. For GS 430 cruise control wiring diagram, see appropriate CRUISE CONTROL under SYSTEM WIRING DIAGRAMS article in ELECTRICAL.