3D printer hotend thermistor troubleshooting testing repair no reading

I deal with this issue a lot. Either on my printers or customers printers I repair. If your hot end is not giving your a temp reading its usually two things. Its either the thermistor or the wire leading back the main board. The easies thing to do is test with a multimeter. Most 3D printers use a 100K thermistors. Depending the ambient temp you multimeter should read between 85K-95K ohms.
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