The first detent is the interval wiper.........not the low speed. If that's your issue, the combination relay might be the culprit.

The combination switch is the turn signal "stalk". It does the turn signals, high beams, and washers.........hence the term, "combination switch".

Wow... I am learning... Too bad I don't have manual for reference basis...
Btw, can you tell me where to look for combination relay? Not in the fuse box??
Thanks

__________________
1987 300SDL 314K mi, counting; #22 Head
1999 E300Turbo 405K original miles
1997 E320 180K mi (Son's)
2002 ML320 (Son's)
1998 S320 140K mi (Son's) sold
1985 300SD 311K mi
1984 300D 324K mi (killed by a hit-n-run turd)
*************************************

.........is this deja-vu?

This thread gets me close to troubleshooting my problem with an 82 300SD that is new to me. On the combo switch, first wiper detent is fast, second is normal and third does nothing! Is this a combo switch issue or a relay issue? If combo switch, any help out there for how to remove the switch and either clean it up or replace it? Thanks very much.