Einleitung
Recently lightning struck near a friend's house and damaged a lot of their electrical appliances... she gave several to me and I've been enjoying fixing them.
She swears this is the best toaster oven ever, so I was excited to repair it... should be easy, right? Just order a replacement relay board online- ha! Discontinued.
After spending 2 hours trying to figure out how to open this thing up, I found others also had the issue and since another iFix it guide showed me how to open it, I'll show others how to fix the relay board for under $20!
The voltage spike cause the circuit board to literally vaporize some of the connections and components, the damaged ones were easy enough to spot, but the transistors were tricky and had to be individually tested.
Blue thingies: are evidently called Varsistors, I found nearly identical ones online at Mouser Electronics for $0.23 (MOV-07D271K)
Black tube thingies: are evidently called diodes, I found nearly identical ones online at Mouser Electronics for $0.13 (1N4004)
Other black thingies: this was the hardest part to get right, these transistors say "discontinued" on the spec sheets, but you can still buy them from other companies, they are C114 E___, you'll see them marked as C114 ES041 or C114 ESQ or etc, but it seems the ___ is not important, only that they are C114 type E, this is because they have built-in bias resistors of 10k & 10kOhms, so you can tell if they are good by using a diode tester (see photo) and then measuring 20kOhms between legs 1 & 3 and 1.3MOhms between 1 & 2 and open between 2 & 3. On my circuit board only transistor T203 was bad. All other transistors tested good. I bought my replacement ones on ebay for $1... but turns out Mouser also had them, but their customer service failed to find them.
Fixing the damaged wiring, I did this by simply connecting and soldering wire on to the board (see photo).
Conclusion, I was lucky the lightning strike did minimal damage and to only have lost one transistor, one diode and one varsistor, it took about two hours to figure out the circuit (and I'm NOT an electrical engineer) and about an hour to replace the broken parts. I purchased extra parts so if it breaks again, I'm ready!
P.S. Shipping cost much more than the parts!
Werkzeuge
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You can see here how the board was damaged by high voltage.
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You can see here how I replaced the missing circuit traces.
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C114 E is the important number when ordering replacements.
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There is another small transistor on this board, which is technically a triac.
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To reassemble your device, follow these instructions in reverse order.
