Heating issues

ive been working on this for a while and figured there was a issue with thermistor. I replaced that but have the same issue of it not even attempting to heat up the block.
The screen reads -15 temp and no matter what I do i cant get it to change back.

When I put the stock mainboard firmware on there with the advii lcd board, it read 0 correctly but obviously didnt work.

This is the “temperature” corresponding to an analog input of 0. In other terms, your thermistor is giving ~0V to the mainboard.

How can 0 be correct?

It looks like you have a hardware issue. Maybe, it is simply the cable that is disconnected in the back of the printer.

By correctly i just meant that 0 is what i expected it to read before attempting to heat.

By disconnected cable you’re referring to the cables on the back side of the extruder, right?
If so, I’ve tried to mess with that and am honestly unsure why whether that’s the issue. That was my first assumption.

Is there a diagram somewhere of where each cord goes? (Fans, thermistor, etc)

I do not know where you are but I doubt that your environment is at 0°C. You should read the current temperature of your extruder, i.e. more of less the temperature of the room. So something around 20°C, isn’t it?

I mean the small board in the back of the printer.

If you have plugged the thermistor in the wrong socket, you have probably burned your mainboard because some of the sockets (for the fan for example) are at 24V! The thermistor pin expects 5V.

Sorry, i made that sound more reckless than it was.
I meant I’ve tried wiggling the cords and such… but otherwise put them into their labeled slots.
What i was asking as a long shot is if the labels are somehow wrong.

Room temperature is 21 Celsius.
Also the bed is heating properly.

20200714_111406 20200714_111410 20200714_111437 20200714_111458

Just wondering. Where is the flat-cable?

I found difficult to follow you and understand what you mean.

I do not understand. Which labels? The ones printed on the board?

Sorry I’m not sure what cord you mean?

The ones here

Does it make better sense what I’m asking about?
Basically i can’t do a thing because my extruder won’t heat. Replaced thermistor and problem persists.

I did also try flashing back to stock firmware but couldn’t get the LCD flash to work for some reason.

There should be a flat-cable connected on that board connecting it to the mainboard in the base of the printer. On your pictures to see a 2-3 cm wide connector on the back where nothing is connected. That is where the flat-cable should be.


I’m headed home now, I’ll look.

No. It is written Heater, it is the socket for the heater. Sorry, but I do not understand what you are looking for. The marking on this board is correct. There is no error.

Gosh I’m an idiot. Brain is burned out i guess. I never plugged the main board ribbon back in.

While I’m here though, i do recall coming across something a while back concerning temperature calibration.
Basically ever since i started using this firmware i have had to set temp 20 degrees below target. I figured this out after plastic kept burning.

In other words, if i want 205 temp, i set it at 185.
I understand this can be calibrated in a config file but have no idea how to.