No heat at hot end

[skyjuice]

I searched the threads and found a similar thread where someone had this issue and found the resistor to be bad. My problem is this, I go to preheat my hot end and bed, bed heats up just fine, but the hot end just stays the same temp and then both temps say DEF, then heater decoupled. I JUST cleaned out a jam in the tip and reassembled FYI. Also, the thermistor seems to be functioning perfectly, it's just that the hot end is not heating at all. Any ideas? I appreciate your input!

[geneb]

Check your wiring carefully. If the hot end isn't heating, it's because it's not getting power.

g.

[skyjuice]

Could it be a fuse? All wires check out ok. This is a brand new hot end, factory assembled and they do GREAT work!

[skyjuice]

Reading 3.3 0hm at resistor, is that ok?

[skyjuice]

Found the problem. Bad thermal fuse. I found out by snipping the actual fuse and temporarily joining the wires and voila (spelling?). I'll see if radio shack has them in stock. Will any thermal safety fuse work within the range of (98C/208F)?

https://www.radioshack.com/products/rad ... 0332263557

[geneb]

Get yourself a multi-meter so you can check things like that without having to cut wires.

g.

[Xenocrates]

Get yourself a multi-meter so you can check things like that without having to cut wires.

g.

Unless he has a specific ohm meter, he has one. It's just he hasn't got much experience with electrical troubleshooting.

Now, on that thread, to find an open in the circuit:

Set meter to voltage mode
Attach one lead to the supply/voltage source.
Use other lead to progressively trace the circuit, touching at each point.
When you see the voltage drop which is around system voltage, your open exists between your previous probe point and the new one. In some cases you want to narrow it further (Using test points built into a board/wiring harness and now need to find faulty trace/component), you can move your probe from the supply to your last test point and slowly advance it along each component, trace, or via until you no longer see voltage drop. Replace whatever comes immediately before that point, and see if it works.

[skyjuice]

Get yourself a multi-meter so you can check things like that without having to cut wires.

g.

Unless he has a specific ohm meter, he has one. It's just he hasn't got much experience with electrical troubleshooting.

Now, on that thread, to find an open in the circuit:

Set meter to voltage mode
Attach one lead to the supply/voltage source.
Use other lead to progressively trace the circuit, touching at each point.
When you see the voltage drop which is around system voltage, your open exists between your previous probe point and the new one. In some cases you want to narrow it further (Using test points built into a board/wiring harness and now need to find faulty trace/component), you can move your probe from the supply to your last test point and slowly advance it along each component, trace, or via until you no longer see voltage drop. Replace whatever comes immediately before that point, and see if it works.

Thanks Xenocrates! You took the words right out of my mouth. I have very little experience with electrical troubleshooting, but I am a fast learner. I am going to follow the steps you provided and see what I can find out.