Pattern Select Switch Snow Mode Circuit: Wiring Diagram
WARNING: This page is about a different car, the 2010 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.
HINT:
(*) Pattern Select Switch (ECT SNOW Switch)
When the ECT SNOW switch is pushed, the switch contact is made and the ECT SNOW mode is selected.
To cancel the ECT SNOW mode, push the ECT SNOW switch once again.
The ECT SNOW mode is automatically cancelled out when the engine switch is turned "off".