Overnight my printer crashed with a thermal runaway. I've had this issue many times. Different things cause a hotend thermal runaway.
1. First Check to see if you are getting temps from the Thermistor
2. Make sure the thermistor and heater cartridge are tight in the heater block
2. Check the thermistor connector at the hotend and make sure its not loose (Your printer might not have one)
3. Check the connections and the mainboard
4. Grab a multimeter and start testing the wires going from the hotend to the main board. This is the most difficult to troubleshoot because its usually intermittent. Move the hotend around and check for breaks in the wires.
E3D Thermistorwww.amazon.com/gp/product/B07...
Beside Multimeter I use
www.amazon.com/gp/product/B07...
My Multimeter Stand on Thingiverse
www.thingiverse.com/thing:450... If you found this video helpful or would like help fund future experiments. please donate below.
Patreon
/ fintechrepairshop
Paypal
www.paypal.me/fintechrepairshop
Sponsors:
www.oc3dtech.com
cinderclaus.com
www.fintechcommunications.com
www.ocdatacabling.com
www.ocdatasystems.com
www.bloodlinefishing.com