Sonoff not turning the lights off

Hello everyonte,
juts flashed tasmota on my sonoff and it´s working fine when I plugged the sonoff in the the AC it appears on my hassio and I can toggle him, but when I putt the lamp to test his keeps the lamps always on, when I toggle I can here the sound and the led turns off but my lamps continues to be on, anyone could help me on this?


May you test the toggle from the tasmota device webpage? After i upgraded my devices i got the same behaviour. I found that in the last firmware the single devices use “POWER1” topic instead of just “POWER”. Oddly enough, “POWER” works to turn on, but not off.

Tried also not working, also tried from the phisical button and nothings happens ligts keeps on all the time

ahh… are you sure that the live and neutral are on the right positions (not inverted)?

tried the both an it keeps the same, something strange ist that when I used the wires from my switch box the lights didnt stop to blink but it kept on always, when I test with only one lamp they keept on always doesent matter the neutral/hot, neither output or input

@ArisSaraiva It should still work if the L and N are reversed for AC current. If you can hear the relay click when you turn on and off then the relay contacts may be stuck in the power on state. Can you do a continuity test on the contacts.

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I tried all the ways, indeed I had a problem during my tests I had a short circuit due to the wire be exposed, still the sonoff is working and is truning on but I don´t know if there´s any other test I could do to see if the relay is the problem, do you know?

You would need a multimeter to test the relay contacts for continuity.

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I have one in my house never tested relays before any tips?

If you turn off the sonoff, the N in is permanently connected to the N out so if you set your multimeter to measure ohms or beep when you join the probes together then you will here a beep or measure close to 0 ohms when you test between N in and N out. You should not get the beep when you measure L in to L out. If you look at the PCB underneath you will see 2 large tracks made of solder. The N is the one that just goes straight through and the L has a gap in it. The gap is where the relay is so when the sonoff has no power it stays open but when the power is on and the relay switched to on, it bridges this gap.


ok great tks I´ll try today, I also ordered a new one and will test this time with no short circuits.

Ok, make sure you test with no power connected.

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yes sir will do apreaciate your concern and help

indeed I´ve just tested and when I touch my multimeter on the line input and on the line output it beeps

That’s not right, it is likely to be just the relay though so you could replace if you want to tackle the soldering. Try hitting it to see if you can free it off, may not be a reliable fix though but worth a try. The relay is the large cube component that goes across the gap I mentioned in the other post.

I´ve ordered another one since I would need two anyway, I´m not keen on soldering anything I´ll try to hit gently and give a try and post the feedback here. Tks once again

received my new one and with ewelink it worked on my test bulb, problem is the firmware is 1.6 and I couldnt flash sonota, and the pin holes are closed with solder and I don´t have the tools to sold this through serial. I think I would have to start soldering everything. Any tips?

I have had a few sonoffs with the solder holes filled. You need an solder sucker on one side of of the hole and your iron on the other. If you don’t want to solder you could try making a programming lead with pins that you can just hold onto the soldered up holes. Maybe glue some jumper cables together. The ones with pins on.

sorry if im too newbie I´m still learning a lot here with all of you, but how I do this programing lead? just hold the cables with the contact, or I just glue some jumpers of my arduino?

Just hold them onto the sonoff contact while you flash. You need 4 wires.