If Vehicle Is Equipped With Mobile Communication System

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

For vehicles with mobile communication systems such as two-way radios and cellular telephones, observe the following precautions:

Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic system.
Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the vehicle's electronic systems. For details about ECU and sensors locations, refer to the section on the applicable component.
Avoid winding the antenna feeder together with other wiring as much as possible, and also avoid running the antenna feeder parallel with other wire harness.
Check that the antenna and feeder are correctly adjusted.
Do not install powerful mobile communications system.