Cruise Control Master Switch: Input/Output

The input from the cruise control master switch to the cruise control ECU is either a 12 Volts ignition feed or an open circuit. 12 Volts indicates that the cruise control master switch is on and the system can be activated. An open circuit indicates that the cruise control master switch is off and cruise control cannot be activated.

Textbook/T4 will not communicate with the cruise control ECU if the cruise control master switch is off.