Circuit Description
WARNING: This page is about a different car, the 2005 Lexus RX 330. However, it is still accessible from the selected car via links, so may be relevant.
This circuit sends an operation signal from the steering pad switch assy to the radio receiver assy. If there is an open in the circuit, the Lexus navigation system cannot be operated by the steering pad switch assy.
If there is a short in the circuit, the resulting condition is the same as if the switch were continuously depressed. Therefore, the radio receiver assy cannot be operated by the steering pad switch assy, and the radio receiver assy itself cannot function.