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I have a DHT11 module that looks exactly like the image below. I also have raspberry pi zero wh.

  • I have connected 3.3V (pin1) to the + on the module.
  • GND (pin6) to the - on the module.
  • I was carefull never to connect anything to 5V

Unfortunately this stops my raspberry from turning on. It doesn't matter if I connect the data cable or not. As soon as those two are connected the power led does turn off. If I try to connect them while the raspberry is on it immediately shuts off. (power led goes off, ssh connection is lost) Am I doing something wrong, or do I maybe have a faulty sensor module here? How do I even start to check for that?

enter image description here

Other side of the module: back of module

enter image description here

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    I didn't look at your picture (I am not about to download ANY file) - but this is unlikely to help. Paste any info ito your Question.Tell us WHAT module and HOW YOU connected it. Your description is unclear. PS try writing in paragraphs.
    – Milliways
    Mar 17, 2020 at 0:27
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    @Milliways thank you for the comment. I have tried to make my question clearer. Is there anything that is still unclear? I don't know if the module has any specific name. The store that I have this from only labels it as "dht11 module" and doesn't provide any datasheets unfortunately.
    – blues
    Mar 17, 2020 at 8:24
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    @tlfong01 I am aware of this and I was very careful to never even touch any of the 5V pins while setting this up. When you say there is "a couple of fatal newbie traps", what others are there that could cause these symptoms?
    – blues
    Mar 17, 2020 at 8:25
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    You need to provide a clear photo showing the connections you have made between the Pi and the device.
    – joan
    Mar 17, 2020 at 9:56
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    It looks like you have a faulty DHT. It seems likely the + pin is shorting to the - pin which will cause a short and cause the Pi to try to reboot. Get a new DHT.
    – joan
    Mar 17, 2020 at 11:12

1 Answer 1

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Answer

As per the comments of @joan and @theashwwanisingla I tested the module/sensor and there is 0 resistance between the + and - pins. So this is simply a broken piece of hardware.


References

(1) DHT11 Temperature and Humidity Sensor User Manual - Components 101 2018jan05

(2) DHT11 Temperature and Humidity Module Datasheet - AoSong

(3) DHT11 Setup Tutorial - Circuit Basics


Appendices

Appendix A - Internal circuit of DHT11

dht11 internal circuit

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  • Sorry to hear the bad news. The short is usually due to bad workmanship. You might like to check to see if the short circuit is caused by bad soldering. Sometimes you can use a hobby knife to fix it. By the way, the following product advert has a DHT11 datasheet a the end. Reference: (1) "DHT11–Temperature and Humidity Sensor - Components 101 2018jan05": components101.com/dht11-temperature-sensor. Good luck and cheers.
    – tlfong01
    Mar 17, 2020 at 12:01
  • Hi @blues, I have taken liberty to add to your answer a reference list and the internal circuit of DHT11. As suggested above, you might like to use a multi-meter to check out any short circuit due to bad soldering. BTW, other newbie traps or mistakes are just careless mistakes, like wrong polarity of power supply, wrong pin outs etc. To avoid careless wiring, I almost always colour code the connecting wires, eg. black for ground, red for +5V, white for +3V3, yellow for signal input to device, orange for output signal from device etc.
    – tlfong01
    Mar 17, 2020 at 14:03
  • And I might have misled you by saying that there are a couple of "fatal" newbie errors. Actually I did not meant those errors also kill the DHT11. Rather they "kills" the projects, or at least stalls the project. For example, it is a bad idea to order just one DHT11 for testing or prototyping. Since the device is only one or two dollars, and the express delivery cost for me is four dollars, so I always order at least two, to (1) To spread the express delivery cost, / to continue, ...
    – tlfong01
    Mar 19, 2020 at 4:10
  • (2) To use the extra devices as spares for pair/swap troubleshooting, cross calibration, etc. R&D guys usually order extras from different vendors to guarantee a "second source" etc. Cheers.
    – tlfong01
    Mar 19, 2020 at 4:10
  • Please accept your own answer with a click on the tick on its left side. Only this will finish the question and it will not pop up again year for year.
    – Ingo
    Mar 20, 2020 at 16:29

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