[SD ///M4]

I fixed the windshield washers on my Z4 M Roadster a couple of weeks ago.
After I checked the fuses and they were all good, I followed the instructions above and removed the reservoir. That was a mistake as it's a lot easier to remove than it is to get it back in position. It turns out that the filter was clogged a little bit, but the primary reason that the washers didn't work was that the windshield washer pump quit working.

I don't know if non-M Z4s also have this but my reservoir has two pumps, the main windshield washer pump on the outside (fender) side of the reservoir and another smaller pump on the front of the reservoir for the headlight washers.

It is totally not necessary to remove the reservoir to remove the pump and the filter. On the M there is plenty of space and the pump just pulls out after removing a plastic retainer bracket that is held in place by plastic tabs on the reservoir, no screws or bolts.

Edited to add: Note that you will lose all of your windshield washer fluid when you pull out the pump!

The filter and associated rubber grommet will also just pull out with a little twisting. It's even easier to re-install the filter and rubber grommet, and the windshield washer pump. When it turned out that the pump needed replacing, I just put the reservoir back in place and when the new pump and filter arrived I just went out and pushed them both into place, snapped the bracket into place, and plugged in the pump. That took maybe 2 minutes.

These pumps are used on a wide variety of auto makes and models, so they are super cheap. I bought mine on Amazon for about $8.00. The filter and grommet was less than $2.00. These are so cheap that if your washers aren't working and the fuses are good, just buy a new filter and pump and replace both of them in less than 5 minutes. Everything's working great now!