# GPIO not control External Relè
**URL:** https://discourse.nodered.org/t/gpio-not-control-external-rele/32795
**Category:** General
**Created:** [12 September 2020 21:36 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795 "2020-09-12T21:36:34Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@sjpagan](https://discourse.nodered.org/u/sjpagan)
#### Post date: [12 September 2020 21:36 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/1 "2020-09-12T21:36:34Z")
Hi all, i have little problem with nodered, i think the problem is the configuration i am using.
i have a relay that activates with 0V, and even using a BC337 i can't get it energized.
it seems to go the loop regardless of the command I issue from Google Home.
This is my configuration images.
[https://postimg.cc/gallery/XNdYzHd](https://postimg.cc/gallery/XNdYzHd)
reading the docs, i read that the GPIOs only give 3.3V and was using a BC337 to ground everything.
Is there anyone who can help me?
also connecting a simple LED I have the same problem, it seems that the voltage does not come out from the GPIO pins
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### Author:  [@ristomatti](https://discourse.nodered.org/u/ristomatti)
#### Post date: [12 September 2020 23:04 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/2 "2020-09-12T23:04:11Z")
I assume you're running NR on a Raspberry Pi as you did not specify this. Have you tried if you can get the relay of LED toggled using some Python code based on Raspberry documentation or tutorials?
Unless you have, it will be difficult to guess if this is a hardware issue or Node-RED related.
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### Author:  [@sjpagan](https://discourse.nodered.org/u/sjpagan)
#### Post date: [13 September 2020 00:00 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/3 "2020-09-13T00:00:54Z")
Yes I have Node Red.
yes i did a test following this tutorial [https://medium.com/coinmonks/controlling-raspberry-pi-gpio-pins-from-bash-scripts-traffic-lights-7ea0057c6a90](https://medium.com/coinmonks/controlling-raspberry-pi-gpio-pins-from-bash-scripts-traffic-lights-7ea0057c6a90) to set it from bash using GPIO09 -\> PIN 21 and it works fine from bash.
if I use the same PIN from NODE RED, it doesn't work
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### Author:  [@sjpagan](https://discourse.nodered.org/u/sjpagan)
#### Post date: [13 September 2020 01:00 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/4 "2020-09-13T01:00:34Z")
This is very disaster ☹ bat work....
[https://postimg.cc/JHZwdcZ4](https://postimg.cc/JHZwdcZ4)
have another solution to exec some action to turn on GPIO pin ?
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### Author:  [@Colin](https://discourse.nodered.org/u/Colin)
#### Post date: [13 September 2020 08:51 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/5 "2020-09-13T08:51:16Z")
Please note that you can paste images directly in here, there is no need to use an external site.
Add a debug node showing what you are sending to the gpio node and show us what it gives. Also show us how you have configured the gpio node (screenshot is the best way).
Do you see any errors in the debug window when you try to drive the output?
Also I presume this is on a pi, did you install node-red using the recommended method in the node-red docs? [https://nodered.org/docs/getting-started/raspberrypi](https://nodered.org/docs/getting-started/raspberrypi).
Finally stop and restart node-red in a terminal and copy/paste the terminal output here please, right up to the point you attempt to drive the output. Use the `` button above this box and paste it in.
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### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [12 November 2020 08:51 UTC](https://discourse.nodered.org/t/gpio-not-control-external-rele/32795/6 "2020-11-12T08:51:20Z")
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