• ** REMEMBER! **The microwave can still shock you even unplugged!!

    ALWAYS discharge the high-voltage capacitor first if you even think your hands will come close to any HIGH VOLTAGE components.

    Jeff mentions this: Anything in the high voltage ( magnetron, capacitor, diode, wires to and from ):
    ...Use a metal ( not the shiny chrome type ) screw driver with a insulated handle to short across ( touch both at the same time ) the terminals of the high voltage capacitor to discharge it.

    From Jeff's site: http://www.applianceaid.com/component-testing.php

    Jake

FIXED HMV3051U Bosch Microwave Keeps Turning On and Off

BigKetchup

Premium Member
Joined
Aug 4, 2018
Messages
13
Location
Las Vegas
Model Number
HMV3051U
Brand
Bosch
Age
1-5 years
So we have this Bosch microwave that keeps turning itself on and off constantly. Sometimes it appears to work correctly for a few minutes when I plug it in after a long period of being unplugged but other symptoms have been that it constantly asks for the time or today when it was turning on, beeping, losing power, turning on, beeping, etc, in an endless cycle. I'm not sure where to go from here or if someone else had this problem and solved it.

I tested the magnetron and it appears to have continuity and testing the door switches and they seem OK as well (two have 0.04 ohms when closed and a third has the same when open).

What baffles me is why it's turning on and off repeatedly; it's getting power but losing it right away. Is there anything else I can test?


Thanks!
 

BigKetchup

Premium Member
Joined
Aug 4, 2018
Messages
13
Location
Las Vegas
Update: I fixed it. There are three capacitors on the main controller board, two of which were bulging. I removed all three with a soldering gun and replaced them with three new ones. Now it's working as normal.

Here's a photo:

IMG_20180819_202541840.jpg

What I'll also say is that some of the buttons weren't working properly at first. Re-attaching the green ribbon that goes to the touch pad fixed it.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
101,437
Location
McMullen Valley, Arizona
Excellent, good job.:)

Thanks for the update!

Jake
 
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