Bosch is a high end manufacturer of appliances. Occasionally things can go wrong, such as fluctuations in temperature. Bosch's policy is to charge for calls to customer service advice, even when the appliance is still under warranty, so it's worth trying these troubleshooting steps before making the call. Bosch refrigerators also have an appliance self-test which you can run.
Check that the plug is inserted into the household power outlet at the wall. If there's no text displayed on the display panel, it is because there is no power to the fridge.
Make sure that the door hasn't been left open if the warning signal sounds. The warning signal means the temperature is rising, and frozen food can be at risk. Visually inspect that the ventilation openings aren't covered by household objects, debris or dirt. Press the "Alarm Off" button to switch off the alarm.
Ensure that the temperature controls are set correctly if the fridge or freezer compartments get too cold.
Check that the water supply is on if the icemaker isn't producing ice. Test the water supply by using the water dispenser on the door. If "IWD Off" is displayed on the panel, the ice and water are supplies are off and need to be turned on again.
Press the "Condensation Heating" switch near the ice dispenser and water outlet on the door if condensation forms on the outside of the refrigerator. If the environment around the refrigerator is too humid, the appliance can compensate for that.
Run the self-test program to identify major faults. Switch the refrigerator off and wait five minutes. Switch the refrigerator on again. Press the "Select" and "Options" buttons at the same time for five seconds. The self-test will commence. Keep an eye on the display. "E" indicates a fault which needs reporting to customer service. The number in the US is 1-800-944-2904.