# LCD 20x4 not working

**URL:** <https://discourse.nodered.org/t/lcd-20x4-not-working/62313>\
**Category:** General\
**Created:** [6 May 2022 20:39 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313 "2022-05-06T20:39:03Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Henrys320](https://avatars.discourse-cdn.com/v4/letter/h/b5e925/32.png) [@Henrys320](https://discourse.nodered.org/u/Henrys320)\
**Post date:** [6 May 2022 20:39 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313/1 "2022-05-06T20:39:03Z")

</div>

I am a newbi and having trouble with lcd20x4-i2c node.

The exported flow:  
[  
{  
"id": "56644a5d047f6885",  
"type": "tab",  
"label": "Flow LCD",  
"disabled": false,  
"info": "",  
"env":   
},  
{  
"id": "31aeed2d21508759",  
"type": "inject",  
"z": "56644a5d047f6885",  
"name": "click",  
"props": [  
{  
"p": "payload"  
},  
{  
"p": "topic",  
"vt": "str"  
}  
],  
"repeat": "",  
"crontab": "",  
"once": false,  
"onceDelay": 0.1,  
"topic": "",  
"payload": "123",  
"payloadType": "msg",  
"x": 90,  
"y": 140,  
"wires": [  
[  
"b6e694397fdc3f8f"  
]  
]  
},  
{  
"id": "b6e694397fdc3f8f",  
"type": "function",  
"z": "56644a5d047f6885",  
"name": "",  
"func": "msg.payload={msgs:[\n {msg:"Hello from"},\n {msg:"MY LCD"}\n]};\nreturn msg;",  
"outputs": 1,  
"noerr": 0,  
"initialize": "",  
"finalize": "",  
"libs": ,  
"x": 280,  
"y": 140,  
"wires": [  
[  
"29e0a6b98f135fe8",  
"48ddc78d65409fe1"  
]  
]  
},  
{  
"id": "48ddc78d65409fe1",  
"type": "LCD20x4-I2C",  
"z": "56644a5d047f6885",  
"name": "lcd",  
"speed": "3",  
"size": "20x4",  
"address": "0x27",  
"x": 470,  
"y": 260,  
"wires":   
},  
{  
"id": "29e0a6b98f135fe8",  
"type": "debug",  
"z": "56644a5d047f6885",  
"name": "",  
"active": true,  
"tosidebar": true,  
"console": false,  
"tostatus": false,  
"complete": "false",  
"statusVal": "",  
"statusType": "auto",  
"x": 450,  
"y": 120,  
"wires":   
}  
]

No errors are received when I run this flow but the lcd shows nothing.  
Any help will be appreciated.

---

<div class="post-metadata">

**Author:** ![MecatronicaMADE](https://avatars.discourse-cdn.com/v4/letter/m/ce7236/32.png) [@MecatronicaMADE](https://discourse.nodered.org/u/MecatronicaMADE)\
**Post date:** [6 May 2022 21:28 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313/2 "2022-05-06T21:28:23Z")

</div>

Hi @Henrys320 First to all welcome to Node-RED Forum, second, before that you share your flow, you should see how to share your flows, with a correct format.  
 ![Screenshot from 2022-05-06 16-27-14](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/c/1c389734365c9b0c758bbee70c86e4cef1da3767.png)  
 ![Screenshot from 2022-05-06 16-26-47](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/2/72f2548dbfee0eec15ae85ed402a0bb7bb6a4501.png)

What hardware are you using?  
What Node-RED Library are you using?  
If you are using a Raspberry Pi, you enabled the I2C communication?

---

<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:** [6 May 2022 23:45 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313/3 "2022-05-06T23:45:08Z")

</div>

Do you have the dependencies installed? (see [node-red-contrib-lcd20x4-i2c (node) - Node-RED](https://flows.nodered.org/node/node-red-contrib-lcd20x4-i2c))

Also it is a good idea - when you have an issue with a node - to check it's GitHub [issues](https://github.com/atsage/node-red-contrib-LCD20x4-I2C/issues) section to see if something matches your issue.

---

<div class="post-metadata">

**Author:** ![Henrys320](https://avatars.discourse-cdn.com/v4/letter/h/b5e925/32.png) [@Henrys320](https://discourse.nodered.org/u/Henrys320)\
**Post date:** [7 May 2022 15:44 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313/4 "2022-05-07T15:44:24Z")

</div>

I am using a Rpi-4 running Ubuntu.  
I have installed all the dependencies.I have tested the lcd with a python script on I2C and it is working.  
i2cdetect -y 1 indicates the lcd address is 0x27.  
Any help will be appreciated.

---

<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:** [6 July 2022 15:44 UTC](https://discourse.nodered.org/t/lcd-20x4-not-working/62313/5 "2022-07-06T15:44:37Z")

</div>

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