1st get yourself a multimeter, or a test lamp (or even make a test lamp with some wire and a 12volt light globe). That way you can tell if you are getting voltage at the faulty item. Note: Washer/wiper probably only works when the ignition is switched to on. Problem 1. : Firslty I'd plug in the old washer bottle/pump and see if it still works. If it does, the switch isnt the problem, its the new washer bottle, or how you have connected it. To test for power at the washer bottle, connect the test lamp to the wires where the washer pump is (disconnect the pump). Press the washer button in the on the dash. Light should light up. If there is no light, you'll need a multi meter to test if the switch is working. Do this by switching the mutlimeter to measure resistance.Then plug both ends into the unplugged washer switch. It should read as an open circuit. Then press the button. It should read close to 0 ohms resistance. If it does, then the switch is working. If it still reads as open circuit then thats the problem. Also you will need a wiring diagram to work out which is the positive feed to the switch. Change the multimeter to measure volts DC 12 volt range should do it, and check if there is a positive feed going to the switch. As for the defroster, check that you have volatge at the rear window. clip the test lamp to the positive feed and the other to earth, and switch it on and see if the light lights up. You can also measure the resistance across the heater grid on the back screen. once again, open circuit means the heater grid is stuffed. It might sound stupid but a simple analogy to understaing how electrics work is to think of it like you would think of water in a pipe. (its electrons flowing in a wire, so its not too different). So for the washer to work power has to flow form the +ve battery terminal to the fuse, then to the dash switch, (which is like a stop valve to use the water analogy). When you press the switch it continues to flow to the pump motor then to ground (-ve terminal). If there are any breaks in the wires, or plug connections have corroded enough to block the flow it wont work. (The electrons acatually flow from the negative to the positive terminal, but forget that, its not important to know). You can clean up plug connections with a piece of dry wet & dry paper.