Navigation system (Navigation Computer): Description and operation (page 2 of 6)

Inputs and Outputs In addition to the vehicle sensor and the antenna inputs, the navigation computer also receives the following: l A permanent battery feed from the passenger compartment fusebox, to power the navigation function. l An ignition switched battery feed from the passenger compartment fusebox, to power the navigation, radio and CD functions when the ignition switch is in positions I and II. l An illumination power feed for switch illumination and LCD backlighting when the exterior lights are on.

Navigation computer outputs consist of those for the ICE system speakers and to the auxiliary CD autochanger, where fitted.

Security Code The navigation computer is programmed with a five digit security code selected from numbers 1 to 7. If the battery or the navigation computer are disconnected, the code is requested on the LCD the first time the navigation computer is switched on after reconnection; this also occurs if a different removable panel is fitted.

The code is entered using the appropriate multifunction buttons. The navigation computer automatically starts to operate when the fifth digit of the correct code is entered. If an incorrect code is entered, CODE is displayed on the LCD to prompt another entry attempt. If an incorrect code is entered three times in succession, WAIT is displayed on the LCD and the unit is disabled for approximately 60 minutes. If the navigation computer is switched off, the remaining disabled time will resume when the power is restored.

Automatic Volume Control (AVC) The AVC feature automatically increases and decreases the audio volume with increases and decreases of vehicle road speed. The AVC feature, also known as the GAL setting, uses the vehicle speed signal from the ABS ECU and can be turned off or adjusted to start at a different vehicle speed. The GAL setting is accessed through the User Menu and can be set to between 0 and +15, where 0 is off and +1 to +15 progressively increase the vehicle speed at which AVC starts to operate.