# MH-Z19C Timeout?

**URL:** <https://discourse.nodered.org/t/mh-z19c-timeout/45330>\
**Category:** General\
**Created:** [7 May 2021 10:09 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330 "2021-05-07T10:09:42Z")\
**Posts on this page:** 19\
**Page:** 1

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**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [7 May 2021 10:09 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/1 "2021-05-07T10:09:43Z")

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Hello !  
I have a small problem with my co2 sensor, the mh-z19c.  
When I first connected it, it worked just fine.  
But now i have the problem, that below the mh-z19 node the report "timeout" shows, with small red dot infront of it.

Has someone the same problem and could help? I don't know what to do.

Thanks and best regards.

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**Author:** ![edje11](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/edje11/32/572_2.png) [@edje11](https://discourse.nodered.org/u/edje11)\
**Post date:** [8 May 2021 10:01 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/2 "2021-05-08T10:01:41Z")

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You have to supply us some more info.  
Post the relevant part of your flow here.

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**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [9 May 2021 12:27 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/3 "2021-05-09T12:27:41Z")

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Thanks for your answer.  
Like I said, at first everything worked fine, but suddenly, without any changes, this "timeout" report appeared. I researched it but couldn't find anything. I hope to find help here.  
 ![Screenshot 2021-05-09 142618](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/3/630bd7a9deb0893e45cd4dd80b78f6f308aca89e.jpeg)

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [9 May 2021 14:30 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/4 "2021-05-09T14:30:11Z")

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What is the full name (nodered-contrib-????) of the node you are using?

add a `catch` node connected to a `debug` node (set to show the complete msg object) to the tab you flow is on.

Also check the node-red log to see if there is anymore information.

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**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [10 May 2021 09:50 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/5 "2021-05-10T09:50:54Z")

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The full name is : node-red-contrib-easybotics-air-quality.

I did connect a catch node like so :  
 ![Screenshot 2021-05-10 114841](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/0/50d3e7d949b598e6f5bfcdb6a18f8cfd3b7609c5.jpeg)

But nothing happened, i got no reports at all and the debug tab on the right side remains empty.

I set the catch node to "all nodes" and also just for the mh-z node. both times no reports.

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [10 May 2021 09:56 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/6 "2021-05-10T09:56:04Z")

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You said it use to work, what has changed? Did you do any upgrades?  
Can you stop Node-RED and then in a terminal start it up and copy the log and paste it to a reply. I want to see if anything shows up in the log.

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**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [10 May 2021 11:37 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/7 "2021-05-10T11:37:28Z")

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I didn't change anything, thats why I'm so clueless.  
This is my first time using node red, how do i do that what you said?

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [10 May 2021 12:22 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/8 "2021-05-10T12:22:49Z")

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What device are you running NR on?

How did you install NR?

If it is a pi, open a terminal and enter ‘node-red-stop’  
Then  
‘Node-red’

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<div class="post-metadata">

**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [10 May 2021 14:00 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/10 "2021-05-10T14:00:32Z")

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I get this report. I know that the bme has an remote error I accidently damaged a wire.

But i don't know why MH-Z19 switches to passive mode.

 ![Screenshot 2021-05-10 155736](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/d/dd178af6199f7eb4c422c16058c1d7bad236a92b.jpeg)

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [10 May 2021 15:18 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/11 "2021-05-10T15:18:05Z")

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Can you answer all my questions and show the full startup log and do a copy paste of it to a reply. Thanks

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<div class="post-metadata">

**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [11 May 2021 07:48 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/12 "2021-05-11T07:48:18Z")

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I Use node red on a RaspberryPi 4B.  
I installed it as discribed here:

[https://nodered.org/docs/getting-started/raspberrypi](https://nodered.org/docs/getting-started/raspberrypi)

I also enabled autostart.

The full startup log is here.

 ![Screenshot 2021-05-11 094650](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/2/92953cb69929d4897feb469e208fb0cbd60503c2.jpeg)

I Hope this time I replied all of your questions.

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<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [11 May 2021 08:38 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/13 "2021-05-11T08:38:12Z")

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What happens if you disable the bme280 nodes?

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<div class="post-metadata">

**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [11 May 2021 08:43 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/14 "2021-05-11T08:43:19Z")

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Everything stays the same.

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<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [11 May 2021 09:38 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/15 "2021-05-11T09:38:29Z")

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did you start/stop nr and check that the bme error messages were gone?

You said that it was all working and then you accidently damaged a wire. Did this happen about the same time as the MH-Z19 node issue occurred?

Which node are you using to read the BME280? Is it using I2c and could there be an issue with I2c.

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<div class="post-metadata">

**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [11 May 2021 10:21 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/16 "2021-05-11T10:21:34Z")

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The BME has nothing to do with it, the mh-z went into timeout way before this thing with the wire's happened. I also disconnected the bme and rebooted everything but the mh-z is still in timeout or passive mode. I also disconnected the mh-z and changed wires but still n passive mode.  
I use the node " node-red-contrib-bme280 : Bme280" for the bme.

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<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [11 May 2021 12:13 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/17 "2021-05-11T12:13:07Z")

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Have you tried checking it outside node-red? Could the sensor be bad?

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<div class="post-metadata">

**Author:** ![Beginner96](https://avatars.discourse-cdn.com/v4/letter/b/48db29/32.png) [@Beginner96](https://discourse.nodered.org/u/Beginner96)\
**Post date:** [11 May 2021 12:21 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/18 "2021-05-11T12:21:38Z")

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Yes i did that to. For CO2 measure it is one of the most reliable sensors.

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<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [11 May 2021 15:00 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/19 "2021-05-11T15:00:58Z")

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I think you should open an issue on the nodes GitHub page.

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [10 July 2021 15:01 UTC](https://discourse.nodered.org/t/mh-z19c-timeout/45330/20 "2021-07-10T15:01:45Z")

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