Max temp error when extruder miswired

I was getting an error stating “Printer stopped due to errors. Extruder switch off Max Temp triggered.”

I tested the thermister at the connector, it read 120K at room temp. Tested the thermister at the connector for the Rambo board, it read as an open. Noticed the wiring colors were different, swapped connectors at extruder, all better.

TL;DR: When you switch the extruder stepper motor connector and the thermister/hotend heater connector you get a max temp error.

Taz 3

Yes, whenever the hotend thermistor pins on the RAMBo read an short circuit (or close to it – this is a setting you can change in marlin), you will see that MAX TEMP error. It’s written that way to prevent a user from accidentally setting the hotend to over9000 and melting it down or causing a fire. This is why you can get a MAX TEMP error when the nozzle is cool to the touch; in that case it just means there is an short in the circuit in the hotend thermistor.

Make sure all your cables are connected… Because I have made that mistake before. :unamused:

If your TAZ Flexystruder tool head is giving you a consistent maxtemp error after you install it, you can also try flipping the cable connector upside-down (i.e. the flip the block of pins that terminates the the bundle of wires coming from the hot end, fans and motor upside down). The 16-pin terminal on the end of flexystruder tool head wire bundle can unfortunately plug into the recieving socket on the cable going to your printer both ways (right side up OR upside down), and mine wasn’t labeled - if one orientation is giving you the maxtemp error, unplug the flexystruder tool head wire bundle, flip the wires upside down and plug it back in! :mrgreen: