Mack Trucks include a simple, digital clock as part of the truck's audio system. Setting the time on your Mack Truck radio takes just minutes. You can also set the clock to display permanently on the audio systems panel.
Press the "Menu" button, located in the lower-right corner of the audio systems panel in your truck.
Press the "Up" or "Down" arrow buttons until the "Clock" message shows on the digital display screen. Press the "OK" button to access the "Clock" sub-menu.
Press the "Up" or "Down" arrow buttons until the "Set Time" option is shown. Press the "OK" button to access the "Set Time" sub-menu.
Adjust the hours' digits to the correct time. Press the "Up" arrow button to increase the number value; press the "Down" arrow button to decrease it. Press the "OK" button to save your changes to the hours' digits. Shift the flashing to the minutes' digits.
Set the minutes' digits to the desired time. Press the "Up" arrow button to increase the digits; press the "Down" arrow button to decrease them.
Press the "OK" button to save your changes and exit the setting process.
