How to Troubleshoot & Replace Whirlpool AP4135653 / D8547912 Capacitor

The unit is a Jenn-Air oven/microwave combo. The oven still had power, so I knew it wasn't the circuit breaker in the house. Found the Owner's manual to see if it had info on a fuse & location. Found No info in the manual. Checked the internet for common problems for this model. Found that they do blow fuses, capacitors & sometimes the magnatrons. Disassembled the oven/microwave combo to remove microwave. I forgot that I had read about the TWO Tamper-Proof Torx screws on the back cover. Found the Fuse was Blown & the Capacitor was Shorted with my digital volt/ohm meter. Tried to find parts locally, but failed to find anything in the Santa Barbara area stores. Went back to the internet to find this site with GOOD prices, but ships same day only till 2pm Pacific Time out of a westcoast wherehouse. Who would think. Order was processed and shipped on Wednesday, I had the part on Thursday afternoon. Installed the Capacitor & the Fuse I bought from Radio Shack. Four Fuses for the price of One here. Set the cover back on & plugged the unit in. Put some ice cubes in a bowl & cooked them for a minute. Everything works as before. Screwed down the cover with all the hardware. I was now ready to install it back into the combo cabinet. That takes Two people, One to slide out & hold the oven/microwave combo & one to plug the microwave into the back of the oven. Pushed the assembly back into the wall. The Microwave was DEAD with NO power. Removed the Microwave unit again from the wall unit to look at the A/C power plug at the back of the oven. NO power at the plug. Found a small square looking item with markings of 20 amp Fuse. Pushed on it a few times, but didn't know if it was a Fuse Holder or Circuit Breaker. Removed sheet metal bracket & metal from top of electronics bay to get access to the Fuse/Circuit Breaker. It is a Resetable Circuit Breaker, but mine didn't Reset. Called the same parts places when looking for the Capacitor with NO luck. It was after 2pm on Thursday, So NO part would be shipped till Friday, So I went to my local Electronics parts store to look for a Breaker. No Luck, but did get a 20 amp Fuse Holder to replace the Breaker. Used one of the same Fuses that went into the Microwave oven. $25 Breaker or a $3.75 Fuse Holder. Fuse Holder!!! I wanted to get it up & working again without ordering another part. Now had A/C power at the plug socket. Plugged the unit in & she worked. Reassembled all of the breakets, cover plates, even cleaned all 3 pieces of glass in the Oven door since it was removed for better Oven access. Been working GREAT for 4 days & should work for several more years, I hope. 

I have a Jenn-Air microwave that didn't turn on and had no lights. It just stopped working completely. I unplugged the unit and had to remove the rear cover using a *security screw kit* that prevents people from opening the rear panel. Once opened, I removed the fuse and testing it with an OHM reader to determine that the fuse went bad. But I also had to determine why the fuse blew and noticed a sticky oily substance under the Capacitor. I used a rubber glove and needle nose pliers to remove the leads to the capacitor and then used the rubber glove and 2 screw drivers to see if the Capacitor was still holding a charge by shorting it and it wasn't. So I ordered a replacement capacitor and fuse. Once installed, I assembled the microwave and turned it on and it worked perfectly. I recommend being very caution when working with the capacitor because I read online that it could hold a very powerful charge, even though it was unplugged. So I was careful to use rubber gloves and tried shorting it to discharge the capacitor before working on the microwave. 

I checked the fuse and found it was bad. I bought a capacitor, but it looked OK so I did not replace.I turned on power and the display turned on and then I heated a glass of water and it works fine. This is my first time I attempted an appliance repair. 

I got my son to fix it, I`am happy and my wife is really happy, thinks. 

After removing the unit from a wall cabinet, dismantling cover plate (tamper resistant T15 Torx required for 2 rear panel screws), I found the fuse blown when measured with ohm meter. Additionally, I noticed that there was a small amount of fluid leakage on the bottom plate under the high voltage capacitor. After ensuring that the capacitor was fully discharged, an ohm meter was again used to test the capacitor finding it shorted. A new part was ordered by 2:00p that afternoon. AppliancePartsPros shipped a replacement immediately and it was at my front door by 10:30a the next day!!! Outstanding responsiveness. The new capacitor was inserted in the microwave. A 20 amp fuse was inserted. The cover was then reinstalled on the microwave. After powering up the unit, everything worked as designed. In closing, outstanding help with a replacement high voltage capacitor received in less than 24 hours from ApplancePartsPros. Way to go guys!!!! 

Troubleshooted panel brkr ok. Oven still dead. Opened cover & chk. Blown fuse. Went bought from radioshack 20a fuse & blow fuse again. Used ohm meter to chk short circuit found high voltage capacitor is shorted on high volt transformer side. Shop around online app has it. Ordered one Instal ordered parts & retest w/ ohm meter chk ok Plug it in working fine.(: fix.