The attached picuture is of a dual slot fuse plug that is located just in front of the main fuse panel on a 1993 300D 2.5. One of the fuses was burned and when I replace it, it immediately burns again. There were two white fuses installed. I have been unable to figure out what they are for. A parts catalog that I have mentions that it might be for heated seats or a telephone but the car does not have heated seats or a factory phone.
Any ideas on what this is for and whether it does indeed need white fuses?