Mercedes2016, if you do not have the fuse chart that came with your car (it is often wrapped around a tool in the spare tire well; some owners move it to the owners manual kit) then do the following: With your VIN (chassis serial number) in hand, please take a look at the first post at
http://www.benzworld.org/forums/w220-s-class/2028353-fuse-charts.html#post8947849. Open the pdf file titled "Fuse Chart Guide." You will use the guide to determine which of the four fuse chart pdf files ending in 1500 through 1800, applies to your car.
In the guide, go to the columns labeled "To Chassis Axxxxxx" and find where your chassis number fits. The chassis number follows the letter "A" in your VIN or serial number. You will likely need the fuse chart whose part number ends in 1600, or 1700; and you can crosscheck the result by the date of manufacture of your car using the date shown on the sticker in the driver's door jamb, just to make sure. Open the fuse chart pdf, also in the first post, that corresponds with the proper number.
That will get you into the fuse diagram that applies to your car.
Depending on your chassis number, the front cigarette lighter fuse is either number 11, or number 86. The fuse charts show the fuse with a number and its amperage - i.e., the chart will show the front cigarette lighter fuse as "f11/15A" or "f86/15A." That means "fuse 11" or "Fuse 86" - each being rated as 15 amp fuses. Fuses are color coded for their amperage rating; some brands use only the color code, others also print the rating on the plastic part of the fuse.
The fuse slots in the fuse box/panel itself have molded numbers in the plastic, where the fuse is inserted; take a close look.
If the applicable chart ends in 1600, the fuse is in the left hand fuse box under the hood; left being defined based on sitting in the car, facing forward. Its exact position is shown in the chart.
If the chart applicable to your car ends in 1700, fuse 86 will be found in a fuse panel at the end of your dashboard, either on the left or right side. Your owners manual tells you how to access the panel. If your car is left hand drive, the panel will be on the right end of the dashboard. If your car is right hand drive, it will be on the left end.