At the top of the EPC net page is a search tab, or hit F11. Enter the part number and see what you get. It will list all the cars that have that part number.
You can then click on the car model and it will pull up the diagram. But for the car it is not descriptive as to where it is.
On a 123.123 it is on page, 54 electrical equipment and instruments, then 045 fusebox and relay. Item number 47. But I don't know if the diagram is helpful for finding it in the car.

Second to find item in the car. Your "interval wiper control". Go to the service manual. Open it to the Electrical Troubleshooting Manual. Then open the "Wiring Diagram" section. At the bottom of the page is a blue tab called "Component Locations" Click on the tab and open the PDF file. Scroll down to page 206 and under "interval wipe control" it shows it is located "behind LH side of instrument cluster" page 202-1 (figure 1 )
This is how you locate the components for your particular model that you selected from the CD.

Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car