Lulzbot Mini 2 hotend

Have been using Mini 2 for a while all of a sudden hot end will not heat up. Swapped out with other hot end that i know works. Using m175 v2 with mosquito hotend. Dont have a muliti meter will be delivered tomorrow. Please need help I’m using these printers for my business cant afford for them to be down

Did you get a low temperature reading, or no temperature reading?

No temperature reading ( 0c ) you probably have a broken wire or bad thermistor.
Low temperature reading (never gets over 30c) and you probably have a bad heater cartridge.

If you’re relying on 3D printers for your business, you should definitely have at least 1-2 more complete 3D printers than you need (never rely on 100% uptime to meet a deadline) and spare parts for any single point of failure so you can always return one to service.

I keep spare:
Nema motors
Thermistors
Heater cartridges
Nozzles
Duplicates of any printhead (to swap while I fix any down printhead)
Filament that can’t be used for anything but repairs
Endstop switches
Wire
Control board
Screen

Sticking to a single model printer and toolhead definitely cuts down on spares, but if you have an equivalent printhead, you can get by as well.

I actually have 7 of them all lulzbots 2 taz6 3 mini 2 and 2 sidekicks 747…I swapped with a print head that I know works. Wondering if wire might be broken after the connection too motherboard

The wires off the thermistors are extremely weak, and sometimes the insulation breaks right where it meets the thermistor, so it grounds out. Once the multimeter gets there, doing continuity tests are easy so you’ll be able to figure out where the break is.