I have a 1990 bmw 525i. once i put in a aftermarket radio,(sony explod). my windsheild wipers, windows, sunroof, dont work,

There's trapped air in the cooling system.

• You need to remove the bleeder screw on top of the radiator when adding water to the expansion tank.
• With the engine running, pour water into the expansion tank till you see air go out through the bleeder screw's hole.
• Just keep adding water until no more air bubbles come out then just put the screw back in place.
• Then fill the expansion tank to it's normal level/line.

Have you found the fuse box, under the bonnet on LHS of vehicle?
In the lid of the fuse box it will outline which fuse controls the function.

ignition switch needs replacement

may be problem on the electronic control board

Here is a thread I found that has a few suggestions that appear relevant:

http://www.bimmerfest.com/forums/showthread.php?t=533112

If you find a solution there post it here for the next BMW owner with the same issue!

New vehicles now have a CPU that controls everything. Removing a component like the radio will result in a confusing side effect of another.
If you put an after market radio in it's place it might not reconnect all the components needed for the CPU. You need to ask if there is a installation kit that goes with your specific make, model of vehicle when installing a aftermarket radio.

I HAD THE SAME PROBLEM, AND IT TURNED OUT TO BE THE WIPER RELAY , LOCATED UNDER THE FRONT WINDSHEILD IN ENGINE BAY, REPLACE THE RELAY.

There should be a fuse box under the dash on passenger side. There are fuses to these and this is probably the issue. It may also be a wiring issue inside the fuse box.

The best thing to do is tuen the key on and teat all the fuses with a 12 volt test light. Replace any fuse that test bad.