2009 Toyota Matrix Owners Manual - Page 174

3-3. Using the hands-free phone system (for cellular phone) n Steering wheel Volume The voice guidance volume cannot be adjusted by using this button. Hands-free phone system on/starts a call (off-hook switch) Hands-free phone system off/ends a call/refuses a call (on-hook switch) Press: Voice command system on Press and hold: Voice command system off (talk switch) 204