{"id":16,"date":"2025-11-12T22:44:44","date_gmt":"2025-11-12T22:44:44","guid":{"rendered":"https:\/\/www.fatcat-engineering.ovh\/?p=16"},"modified":"2026-07-16T08:19:13","modified_gmt":"2026-07-16T08:19:13","slug":"fix-my-dishwasher","status":"publish","type":"post","link":"https:\/\/www.fatcat-engineering.ovh\/index.php\/2025\/11\/12\/fix-my-dishwasher\/","title":{"rendered":"My lazy dishwasher"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

When a tiny component can force to do the dishes manually !<\/strong><\/p>\n\n\n\n

After a looooong<\/strong> period of procrastination, I finally decided to deal with my dishwasher. The soap dispenser wasn\u2019t opening properly, cleaning results were getting worse, and my solution had slowly drifted toward either recycling<\/em> dishes or running the machine in extreme 60 \u00b0C mode<\/em> like a barbarian.<\/p>\n\n\n\n

Before opening anything, I stumbled upon a video by Technology Connections explaining dishwasher cycles in absurdly great detail. Who would have guessed that the world of dishwashers could be that<\/em> fascinating?
Highly recommended if you want to look at your kitchen appliances with new respect:
\ud83d\udc49 https:\/\/www.youtube.com\/watch?v=DAX2_mPr9W8<\/a><\/p>\n\n\n\n

That video was the final push. Time to investigate.<\/p>\n\n\n\n

———– LET’S OPEN THE VICTIM ——–<\/p>\n\n\n\n

The soap dispenser was not closing anymore, it’s a very simple device: a small plastic enclosure, a spring-loaded trap, and a tiny actuator that releases the soap at a precise moment during the cycle. Simple, elegant, and usually very reliable.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

My dishwasher is an IKEA Reng\u00f6ra<\/strong> (Prod. No. 911 535 083 02).
No big surprise here: most European kitchens are full of IKEA cabinets \u2014 and no big mystery either, IKEA doesn\u2019t manufacture their own appliances.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

In this case, the unit is an Electrolux OEM<\/strong>, clearly visible on the identification sticker.<\/p>\n\n\n\n

———– Getting hands dirty ——–<\/p>\n\n\n\n

Opening the door panel was easy \u2014 just a few screws. As soon as it was open, the issue was obvious:
the mechanical actuator driving the soap dispenser was completely burned out<\/strong>.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n
\"\"<\/figure>\n\n\n\n

I removed it, cleaned everything, and ordered a replacement using the remaining markings and a bit of Google Image magic. 20 \u20ac<\/strong> later, a new actuator arrived. Luckily, the surrounding plastic parts were enough and still usable.<\/p>\n\n\n\n

Side note <\/strong><\/h3>\n\n\n\n

This actuator is not a solenoid<\/strong>.
It\u2019s a thermal actuator<\/strong>: a small heating element that slowly expands when powered, creating a linear motion that triggers the soap door. Slow, quiet, cheap, and perfect for this application.<\/p>\n\n\n\n

— End of side note <\/strong>—<\/p>\n\n\n\n

After installing the new actuator, I tested it \u2014 and immediately noticed something odd -> The actuator was constantly powered<\/strong>.<\/p>\n\n\n\n

That\u2019s not how it\u2019s supposed to work.
It should only receive power at a specific point in the wash cycle. Constant voltage means it can\u2019t reset properly\u2026 and it will eventually burn out again.<\/p>\n\n\n\n

So the actuator wasn\u2019t the root cause. Time to go deeper<\/mark><\/strong>.<\/p>\n\n\n\n

This meant pulling the dishwasher out of the cabinet (yes, hoses, water, fun stuff).
At the bottom, well hidden, sits the main control PCB<\/strong>, inside a white plastic enclosure.<\/p>\n\n\n\n

\u26a0\ufe0f Important note:<\/strong>
I of course<\/em> worked with the dishwasher completely disconnected from mains power.
This is not optional. This stuff can<\/em> kill you.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Tracing the wires from the soap dispenser led me to the PCB. There, I found a small triac<\/strong> controlling the actuator. 0103MN<\/p>\n\n\n\n

https:\/\/www.alldatasheet.com\/datasheet-pdf\/view\/293603\/NXP\/Z0103MN%2C135.html<\/a><\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Desoldered it. — Tested it. -> No issue. Triac was fine. <\/p>\n\n\n\n

Testing a Triac with a multimeter is suprisingly easy : https:\/\/hubbellheaters.com\/api\/media\/file\/How_to_Test_a_Hubbell_Triac_Component.pdf<\/a><\/p>\n\n\n\n

Then I noticed something else, Next to the triac was a tiny SMD capacitor<\/strong>, about the size of a grain of rice. After desoldering it, I noticed a microscopic hole in the casing \u2014 so small I only spotted it using my phone camera.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Measured it. -> Dead short.<\/strong><\/p>\n\n\n\n

Even more interesting: this capacitor didn\u2019t look like a proper X2-rated capacitor<\/strong>, which is normally required for mains-related filtering. Suspicious design choice.<\/p>\n\n\n\n

Luckily, the PCB had another identical circuit nearby<\/strong>, still intact. By measuring that one and checking the resistance of the thermal actuator\u2019s heating element, I could estimate the correct value.<\/p>\n\n\n\n

This circuit is a classic RC snubber network<\/strong> \u2014 used to:<\/p>\n\n\n\n

    \n
  • suppress voltage spikes<\/li>\n\n\n\n
  • reduce EMI<\/li>\n\n\n\n
  • protect the triac when switching inductive or thermal loads<\/li>\n<\/ul>\n\n\n\n

    It\u2019s extremely common in appliance electronics.<\/p>\n\n\n\n

    I found a suitable replacement capacitor locally. Not SMD, not the same package \u2014 but electrically compatible. This was revival surgery<\/strong>, not aesthetic surgery.<\/p>\n\n\n\n

    Some creative lead extensions, a bit of glue, proper insulation, and the PCB was ready to go back.<\/p>\n\n\n\n

    ——– DRUM ROLL ——-<\/p>\n\n\n\n

    Everything reassembled. Dishwasher back in place.
    First test: voltage across the actuator terminals.<\/p>\n\n\n\n

    \ud83d\udc49 0 V at idle<\/strong> \u2014 perfect.<\/p>\n\n\n\n

    Ran a full wash cycle.
    Soap dispenser opened exactly when it should.<\/p>\n\n\n\n

    Success.<\/p>\n\n\n\n

    <\/p>\n","protected":false},"excerpt":{"rendered":"

    Meet the dishwasher that decided to do the bare minimum.<\/p>\n","protected":false},"author":1,"featured_media":37,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-16","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/posts\/16","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/comments?post=16"}],"version-history":[{"count":4,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/posts\/16\/revisions"}],"predecessor-version":[{"id":57,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/posts\/16\/revisions\/57"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/media\/37"}],"wp:attachment":[{"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/media?parent=16"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/categories?post=16"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fatcat-engineering.ovh\/index.php\/wp-json\/wp\/v2\/tags?post=16"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}