Buy micro switch - Microwave Ovens

Most microwave ovens have up to 4 micro switches in the door latch, it's a safety interlock. These can go bad, and cause the oven to not function.
Micro switches are pretty inexpensive, and can be replaced. You need to open the oven, and then identify exactly which micro switches you need. Both my current microwave ovens have done this, and I've replaced the bad switches. They work fine now.

Well, it DOESN'T work.

I'd suggest that the magnetron has failed.

Weigh it in at a scrapyard and buy another. You can get one from an auction house for £5.00.

one or more of the door micro switches are open or shorted..the micro switches tell the unit the door is closed and safe to use.the micro switched are marked normally open or closed..take note when replaceing them..also their is a actuator lever that tells the switch to close or open..it is plastic and connected to the door latch..it can be broken off or bent from heat,,its plastic..make sure its in place and working the micro switch

This usually means that a micro switch is faulty, check the micro switch and replace if faulty, there should be two micro switches

Be-safe, Un-plug your microwave oven ,

Open the microwave cover ,
Close and open door few times to check the door latch(es) and switch(es).
Door switch assembly may has one or more micro switches.( Most switches are black or grey and about 1,25 in long X 3/4 in wide X 5/6 in thick with two or three wire connections).
Making sure door latch close and open these micro-switches.

You can hear the switch "clicks" when small switch pin or lever is pressed.

Sometime these door micro-switches pin or lever get stuck or broken.

You can take couple pictures before remove wires or micro switches

You can buy these switches for about 3-7 dollars online. Some web sites have video showing how to check them. (Using Volt-Ohm meter)

I have a r-1482 model so I don't know how close they will be. The biggest issue I found so far with my particular model, yours my be the same, is the door safety micro switches fail primarily from opening the door while the unit is in the process of cooking which causes them to arc and burn the contacts resulting in premature failure. With an ohm meter, check the resistance of the contacts of each switch individually with the COM terminal lug temporarily removed and ensure the closed resistance is 0 ohms and infinity when the contacts are open. Measure from the COM terminal to the terminal in use either N.O. or N.C., with the switch button NOT depressed the N.O. will be open while the N.C. will be closed and with the button depressed they will be opposite, in other words N.O. will be closed and N.C. will be open. Another thing to check is that the door hooks aren't broken (they activate the safety switches. Should you remove the switch bracket to replace the micro switches, make sure you wire the switches exactly the way they were COM to COM, NC to NC & NO to NO, mount them in the bracket the exact way they were and adjust the bracket so that the switch buttons are just to the point of being fully depressed and no more when the door is fully closed. The micro switches may be different in model numbers but you can sub with a micro switch that has all three COM, NC, NO terminals and only use the terminals in use for the given switch. I used Omron p/n: D3V-16G-1C25-K from Mouser Electronics (800) 346-6873. Since you didn't indicate the control panel was not operational I won't go into that area. I can't say if the timer will count down or not if the micro switches are bad, but it's a possibility, further pointing to the switches. If the control panel or MW tube is bad it's my recommendation to buy a new oven, though you can get new MW tubes, diode & capacitor, it's not worth the shocking experience to the human body, not to mention the MW radiation.
Good luck if you still have the oven and decide to take it one step further.

you mean it want power up or want work when you press the star buttom?
1. check the fuse if no power.

2. If it doesn't work when closing the door after setting timer it is the micro switch that the metal lach hits when the door close.

3. unpluge the micro wave unscew the scews to the cover of the microwave remove the cover. up front by the door you will see the micro switch maybe (brown,black,white,red/white ) what ever color it is disconet it take it to the hardware store buy a new one and replace it,themreasemble your micro wave.

ge over the range microwaves have this problem . for some reason the plastic sort of melts but not realy (please check hinge for wear and adjust if ness ) , it just gets out of shape from the heat and this makes the switches not work properly . most likely the micro is too close to the stovetop . see your manual about that and you can buy the slideing plastic parts where the switches are , its just big $$$$ if the micro is to close it will happen again GOOD LUCK

I can't help with the keypad, but a defective door safety switch can also cause this. They sometimes get out of alignment.

Geno

You are decribing a typical Door Safety Switch problem. The Door Safety Switches has Failed.The Door Safety Switch is designed to shut down the Micro in the event the Micro is still cooking when the door is being opened. The first "Click" of the switch cuts off the "Cook". If it does not cut off the "Cook", the second "Click" blows the power. Otherwise it would "Cook" with the door open, and I need not to tell you how DANGEROUS that could be. It first Tripped the Circuit Breaker which supplies power to the Microwave. After Re-Setting the Breaker the same thing happened except this time the Micro is DEAD- not even a light working. Yes, there is a line FUSE inside the Micro. You however need to address the Door Switch SHORT before replacing the fuse. If not, it will just Blow The Fuse Again, and Again, until the Short is corrected.
Call around, ask How much to replace a Door Safety Switch.
Good Luck!