Odd windshield washer issue, 2011 XC90

[kamikazze]

Hello everybody!

I'm driving 2011 XC90 2.5T, European version. Recently I've started getting an odd issue with the windshield washer which wasn't present before. The thing is what when I've just started the car and pull the windshield washer lever to spray the windshield, it first sprays the rear window, but engaging the windshield wipers. If I then pull it again it might spray the rear window again one more time, then always spraying the windshield. What's interesting, if I then push the lever to spray the rear, it's always spraying the windshield instead without starting the wipers. So in short:

First one or two lever pulls after starting the car always spray the rear window, then after these, regardless of pull or push - it's always spraying the windshield only. So I can't spray the rear window at all after first pulls. I've connected VIDA and checked the error codes - there are none. Also tried activating the windshield washer from VIDA - it's activating for windshield but not engaging for rear (can't hear even relay clicking).

The windshield pump on my car is a two-way one, single pump for both windshield and rear window. It has two-contact connector and two tubes, and when you pull or push the lever, relay basically just switching polarity for the pump motor to spray windshield or rear. So at the moment it seems like first two pulls engaging the pump in reverse, then all subsequent ones engaging the pump in primary direction.

So the question is: can it be a defective pump (I've changed the pump recently shortly before the issue started as my old pump degraded), or it's most likely an issue with relay itself or wipers control lever? Where to start checking and how to check exactly?