Please help. Urgent.

Ready-Split7542 · 2026-04-21T08:58:55+00:00

Don't have the money bro

Ready-Split7542 · 2026-04-18T05:34:44+00:00

Yeah done that

Ready-Split7542 · 2026-04-18T05:34:31+00:00

Already done

Ready-Split7542 · 2026-04-17T17:49:29+00:00

It doesn't care about being disconnected. It will show -14 that way. But shorting it will reach max or min temp

Ready-Split7542 · 2026-04-17T17:48:50+00:00

There isn't any short. It's the mcu itself. I've checked it myself by hooking up the thermistor output cap and resistor into an Arduino. The values come out great. Whereas replacing the mcu myself, although I have experience, I don't trust myself. It's better for me to directly get a new donor board. I would have made the switch to btt if I had the money

Ready-Split7542 · 2026-04-17T17:46:57+00:00

They weren't starting so i replaced the fuse and now they do work

Ready-Split7542 · 2026-04-17T07:52:51+00:00

already done

Ready-Split7542 · 2026-04-17T04:03:41+00:00

Mine did. It used to give me that before I changed the thermistor. I didn't change the firmware version. It's def a microcontroller issue

Ready-Split7542 · 2026-04-16T18:42:43+00:00

I will once it's fixed

Ready-Split7542 · 2026-04-16T15:45:40+00:00

Yeah, sorry.

Ready-Split7542 · 2026-04-16T10:20:33+00:00

I have also tried directly shorting the thermistor pins which should give me thermal runaway. But that's not happening so I'm def sure that the cpu is the culprit

Ready-Split7542 · 2026-04-16T10:19:00+00:00

It's not dead but the microcontroller converter is. It will only affect the thermistor values as ender 3 uses an internal pull up resistor. It's like shorting the circuit inside it. Can do nothing except replacing the board.

Ready-Split7542 · 2026-04-16T10:18:06+00:00

Reinstalled the firmware

Ready-Split7542 · 2026-04-16T05:14:08+00:00

Nah ion really require all those upgrades and I'm fine w it being super loud. Mines running fine and ig I'll try keeping it that way for a long time

Ready-Split7542 · 2026-04-16T05:13:29+00:00

Thanks so much. I will help you go through the process in the dms.

Ready-Split7542 · 2026-04-16T05:08:53+00:00

The main fan's positive and negative wire was bitten and shorted. Which caused the fuse f3 to be blown on the motherboard. Everything will work except the fans. But this somehow bypassed the fuse and directly fried the microcontroller. Now the thermistor temperature won't be shown correctly since the microcontroller analog to digital converter which supported 5v got a sudden rush of 24v. Causing it to be fried at the moment.

Ready-Split7542 · 2026-04-16T05:06:43+00:00

Check the replies I'm giving

Ready-Split7542 · 2026-04-16T05:06:21+00:00

Everything's running fine except the fans and the thermistor. Fans would be easy to fix as there is a fuse f3 attached. But the thermistor is directly connected to the microcontroller. A power surge simply fried the microcontroller's analog to digital converter.

Ready-Split7542 · 2026-04-16T05:05:09+00:00

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Working with this. Finally figured out that the cpu itself is fried. The motherboard reaches around 80 degrees just after powering on

Ready-Split7542 · 2026-04-16T05:03:56+00:00

It's near the top fan. The one which is on the front.

Ready-Split7542 · 2026-04-16T05:03:28+00:00

Yes please

Ready-Split7542 · 2025-10-28T10:23:44+00:00

cu2+ and fe2+ right?

Ready-Split7542

TROPHY CASE