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De'Longhi KG79 grinder problems

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My dads KG79 grinder is having problems and we are wondering if anyone knows how we could fix it?

It has lost power in the first stage of grinding and takes a while to get enough power to grind coffee, even the light goes off after a second.

I have uploaded a video with my KG79 for comparision.

On the same setting the machines ground 14.6g (mine) and 9.4g (dads) of coffee.

We took it apart to see if anything looked off and gave it a clean.

He does not drink enough coffee to want a new grinder so a fixing it would be great.

My first thought was maybe there is a problem with one of the capacitors but I really do not know much about electronics.


The grinder on the left is my one (the working one) and the one on the right is the faulty one.

Iberital MC2, Gaggia Classic, Aeropress, v60

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The one we have at work died recently. We changed out the large yellow capacitor on the power board (can't remember what spec, but you can't miss it.) That brought the machine back to life and it's been fine ever since. Different problem to yours I know, but maybe worth a punt - the caps are cheap. It could also be the timer circuit. You could always 'hot wire' the timer and use it in manual mode. There are also two micro switches, one on the lid, one on the grind box. If these are not 100%, they may be cutting the machine out early. Good luck with your investigation.

Edited by lake_m

GS3 MP, Ceado E92 and E37s, Feldgrind. Niche.





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Yea, I was thinking about replacing the yellow capacitor, its worth a try I guess. I dont think it has anything to do with the timer or the microswitches because it is not cutting out early.

Iberital MC2, Gaggia Classic, Aeropress, v60

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I was experiencing the same problem on a 2 year old KG79 but with much worse effect.

I'd have to switch the grinder on and off multiple times before it would continue grinding for more than a second.

The button light would only be illuminated for this second (even when eventually it continued to grind)


On replacing the big yellow capacitor (X2, 275V, 0.47UF) the grinder functioned flawlessly.


When ordering your replacement capacitor can i recommend you check the lead length.

The one i ordered had a picture of a cap with long leads but was sent a different "footprint" cap with very short leads

A bit of creative soldering later and it was up and running though.

Due to its positioning on the circuit board the "footprint" doesn't really matter although the lead length will


If you go for the Panasonic one can i recommend a ECQUAAF474M rather than the short leaded ECQUAAF474MA

Hope this helps someone fix their grinder too!




P.S. As there may be multiple versions of this grinder with different internal components. Make sure you check the values on the cap before replacing!

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Hello, i have KG79 since 2 years and i have the same issue. The led stop after 1 seconds and the grinder not have too enough power for destroy coffee.


My Big yellow capacitor return value when i try with multimeter but the small yellow capacitor return nothing. (0.1uF) I bought new one. I am waiting for shipping and when i receive it i can write here if my problem is solved.


If the small capacitor change nothing i will try with the big

Edited by louit

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The small yellow capacitor changed nothing (near the power).


The big yellow capacitor on the motherboard fix the issue. Now the led stay on and the motor have. Enough power for destroy coffee. Be careful when you remove the original capacitor because the mother board is not good quality. For 8€ my grinder is fixed :) (I bougjt bad capacitor the first time and the shipping price is more than the capacity price )

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just to share that i was also having the same problem (not enough power to grind coffee, even though the grinder would work without coffee in it). 

i changed the big yellow capacitor on the motherboard and its working again. the leg distance was different than the previous one so i just used the old capacitor's legs to make an extension for the new one. i did realise though that there is an extra hole beside the right leg — has anyone tried using this one instead for the wider capacitors? they are connected on the board... 

i feel very saddened to think that this is still the practice among big companies. initially i brought my machine for repair at delonghi they said that 1. they didnt know what the problem was and investigating would cost minimum €70 (+ the repair) and 2. that i'd better buy a new one because it would be cheaper anyway. hope this thread can reach as many users as possible!! 

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