Hardened exruder temperature over run

So my newly installed left hardened .4mm extruder failed during an 2 hour print with PLA
It first failed with “temperare control abnormal”
Then it would show -30C
I removed, measured resistance of temperature probe (107 ohms) reinstalled, was able to heat to 220C to remove fillament then it flashed “unsafe heating in left extruder, turning off heating).
I removed again, not the resistance is 119 ohms.

I emailed support throughout, they keep babbling about me filing plastic parts, adding spacers. the extruder looks identical with the stock .4mm, and it goes all the way in.

To me this stinks as an defective pre-amp on the extruder.

Oh and the ribbon is slightly bent, and support says will only send me another ribbon cable once i try their useless spacers/ filing. It’s not the contacts, ppl.

I cannot replace with original extruder, that one does have a broken thermistor cable bc of a pla mess all over it.

Waiting for replacement stock extruders now to test, they say ordered fullfilled but has not left warehouse in 3 days.

Should have listened and get the Bambu, rhe J1 built quality is horror

@alintolea I had exactly the same problem after changing one of the nozzles. In my case it was to much strain on the heating block cables. Once i let them loose, the problem went away…

well, it seems that the ribbon cable IS the culprit. I bent the ribbon cable and the temperature went to ambient. I let it go, back to -30C.

This is a manufacturing defect of the ribbon cable and snapmaker needs to resolve this ASAP, send people ribbon cables, and actually, find BETTER ribbon cables and send them to everyone, asap.

well, it’s the ribbon cable and this needs a fix and a recall.
snapmaker j1 extruder ribbon cable failure

This is a repeatable failure point for this machine and needs a fix - I have had luck (so far) with lighter, ‘concertina’ third-party cables - but they jangle around and don’t look great. Snapmaker just keeps blaming their shipping partners for damaging them in handling, and shipping the same design. They aren’t damaged on arrival, but get so pretty quickly - especially printing full beds. Very poor form.

In case anyone gets an exact specification or a place to order these cables: please share! I guess affected users might be happy to have an alternative to waiting for replacement from Snapmaker.