Partner Headlight and Wiper system malfunction

Hello to everyone ,
I would like to summarize my problem briefly. When I told the problem that I could not find a solution in the repairmen, it does not come to me to say change, maybe it can be repaired so I would like to get your opinion.
I have a 2007 Model Partner long Chassis vehicle. Since the remote control lock did not open last night, I opened the door manually and turned the ignition and the headlights turned on spontaneously. The vehicle worked, the headlights remained on, although it was off. When it turns on and then turns off, it goes out but then turns on again. Sometimes he never does that, sometimes he repeats. When the door is closed while the ignition is off, the warning sound starts to sound even though the headlights are off. When the headlights are turned on, the horn does not work when it turns on, but when I turn it on, it does not work when it turns on or when it passes. Sometimes it goes out depending on this

Also, the rear cover wiper works from time to time in closed position. I saw him working in the park the other day. Then I did not come across. It turns on when it turns on and off in both problems, then repeats.
I would appreciate if there will be an assistant for the solution, because repairers said this arm is broken, but now I want to get an idea because the repairers I went to for other reasons have changed parts without understanding.
For example, the battery is low, but the man wants a starter replacement. It is hard to find qualified repairers in this period.

If the wiper works in rainy weather, it may be taking water from somewhere and making chassis.

I came across except rainy weather. The headlight problem is more troublesome than that.