Thermistor for Z603S bed : replacement?

Tesla Dominico

Does anyone have a wiring diagram and replacement notes for the thermistor on the bed?  Mine is stuck at 17C regardless of how much the bed is heated up.   Any hints on what to replace here?

Stephen Todd

You could use a multimeter between the thermistor plug pins - you should get a reading of about 100K ohms at room temperature of 70c - if the reading is OK, then its usually the controller board gone faulty

Samuel Pinches

It’s a 100k thermistor would should read 100k at 25C not 70C. 

Measuring resistance is the best way to check.

Any idea when or how it started?

I don’t have a wiring diagram but I’m familiar with how to answer questions about it.

Stephen Todd

Yes, 25C - the "authorities" use metric here in UK, but the population don't like it and get confused between F and C, as a lot of people still use fahrenheit, miles, feet, inches, etc.

Stephen Todd

Unless the Z603S is different to just about every other 3D printer, it will be a standard 100K NTC glass bead thermistor - which you can get from Amazon, eBay, gearbest, aliexpress, etc.

It will be soldered directly to pads on the underside of the bed, or taped to the bed with kapton tape (polyimide adhesive tape)

I buy bare lead thermistors and solder them to existing wiring, or direct to solder pads - they are not polarity sensitive, being a simple heat sensitive resistor