Error message 'Thermal runway E1'?

So I am printing my first articulated dragon and the printer has stopped twice now with a high pitched noise, what is going on? Er

error message ‘Thermal runway E1’?

It means the hotend is not heating like it should. Either the thermistor or the heater cartridge are at fault. Check the wiring to both to see if the wires are damaged, especially near the heat block. Check to make sure both the thermistor and heater cartridge are properly seated in their respective holes. If that does not show any issues, open up the mainboard housing and check if the thermistor or heater cartridge wires have become umplugged, or in the case of the heater cartridge, if the wires have become loose and slid out of the clamps that connect them to the mainboard.

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@MicroFarmModels is totally correct. My personal take is just replace one (thermistor usually in my estimation) and see if it fixes the issue if not replace the cartridge too. They are inexpensive consumable parts, it isn’t worth much effort troubleshooting IMO as it is almost certain you will replace one or both anyway.

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That’s a bit over my head! Are there any pics or videos to show me how? I don’t see why this has happened after only 5 months. Someone also mentioned unscrew the screw holding the hotend for the thermistor but I don’t know where to start and now my dragon print is ruined. Replacing the thermistor seems a big job.

Check YouTube, there probably will be videos on it. It really isn’t hard at all though. First thing to do would be inspect your hotend. You’ll probably need to take the hotend shroud off to get good access. There will be two pairs of wires running to the heat block. The thick pair is connected to the heater cartridge. The thin pair is for the thermistor. Like Kitedemon said, odds are it is the thermistor that is the issue. Although I personally have a heater cartridge wire fail once, thermistor failure is in my experience much more common. The thermistor is held inside the block with a small screw. Remove the screw and pull the thermistor out of the block. Chances are you will see that the wires to it are damaged in that area. Open up the main board housing, trace the wires to identify which set of wires goes to the hotend thermistor, then tie a new thermistor to the old one, and pull the wire through. Plug the new one into the board, and insert the thermistor into its hole in the heat block, then use the little screw to hold the thermistor wires back in place. Once you have done this, chances are the problem will be gone.

What I would do personally though, is, before routing the new thermistor wire, just plug it into the main board, and run it straight to the hotend to test first, just in case the thermistor isn’t the problem.

As to why it failed, it could be a few different things, inadequate strain relief, screw on heat block too tight, therefore pinching the wires and causing damage leading to premature failure( that screw does need to be snug though), product defect, or some other thing that I haven’t thought of.

It’s frustrating having these failures, but the reality is that it is part and parcel of owning a budget 3d printer. Failures like these will inevitably happen. How well you maintain your printer will to a large degree dictate how frequently failures happen, although some failures are simply unavoidable. My advice is to look on the bright side. This is one of the simpler repairs to diagnose and fix on a printer, and it is a good place to start getting comfortable with working on your printer. I guarantee that it is a skillset you will want to develop if you want to enjoy 3d printing.

Thamk you so much my friend I will have a look tomorrow.

FIXED! I just wanted to say a BIG Thank You to everyone with their suggestions. My Thermal Runaway E1 has been fixed. I never for one moment thought that loosening a tiny screw and retightening it would work but it did. The temps have stayed consistent throughout. I am so please with the end result. Thanks all!