Out of the blue, Voron 2.4 Part Fan turns on at startup.

[nickpeck47]

I have been using my Voron 2.4 rev c (LDO) kit for a week now and it has been great.  Then today, I turned it on and the part fan is going full bore, even before Klipper is loaded up.  It hasn't done this before so I'm kinda stumped as I have made NO changes to the printer.cfg file.  I tried moving it from one pin to another on the Octopus 1.1 and it doesn't matter as it just stays on.

I haven't made any changes at all to the printer wiring wise as it's been running great (like I said).  In the slicer when I print, I have it off for the first layer, so I tried a print just now and that fan is just on solid no matter what.  The dashboard shows it off once klipper loads up, but it is going.  Any idea what else I can check?  Everything else is working as it should.

**All of the software is completely up to date as well**

Edited May 18, 2023 by nickpeck47

[mvdveer]

1 hour ago, nickpeck47 said:

Any idea what else I can check? 

I have had this happen before with a loose thermistor connection. Might be worth checking. What happens when you heat the hotend - does Klipper throw an error?

[nickpeck47]

Just now, mvdveer said:

I have had this happen before with a loose thermistor connection. Might be worth checking. What happens when you heat the hotend - does Klipper throw an error?

Nope, I threw it a print and it printed, even though I have no part cooling for the first layer, it stayed on.  Basically, the fan just turns on after I hit the power button and just stays on the whole time.  I'll check the connectors on the SB PCB again.  The bed and hot end heated up just fine.

Thanks

[PFarm]

@nickpeck47 Switch your parts' cooling fan with the exhaust filter fan and see if it is fan circuitry or an issue with the wiring. If the exhaust filter fan duplicates the issue then there is something wrong with the Octopus fan circuit. 

@mvdveer correct me if I'm wrong a ground sent to the fan is what turns it on, correct? If so could be a ground source in the tool head PCB.

[mvdveer]

10 minutes ago, PFarm said:

round sent to the fan is what turns it on, correct?

That is my understanding as well. If I remember correctly it should be connected to AGND which offers fan control. 

[mvdveer]

Looking at the LDO diagram the fan automatically selects 24V - can be set to 5V. I assume your fan is 24 V.

[nickpeck47]

49 minutes ago, mvdveer said:

Looking at the LDO diagram the fan automatically selects 24V - can be set to 5V. I assume your fan is 24 V.

Yes, it's 24v.  I have gone over all the wiring, and it all looks fine, I haven't touched it since I started printing on it regularly for the past week or two.  I haven't changed anything in the printer.cfg recently either, just strange it's been fine until today.  I don't have the back filter installed, just the nevermore, which works fine.

Undoing the Part Fan cable completely (from LDO PCB to the Octopus), it's still turning on and running (I'm guessing from the larger cable cluster coming from the SB PCB).  All of the cables in the cable chains look good, nothing is pinched or anything like that, I did my best to keep it tied down but not super tight as to cause any issues.  Trying to think of anything else to rule out.  
 

Edited May 19, 2023 by nickpeck47

[nickpeck47]

13 hours ago, PFarm said:

@nickpeck47 Switch your parts' cooling fan with the exhaust filter fan and see if it is fan circuitry or an issue with the wiring. If the exhaust filter fan duplicates the issue then there is something wrong with the Octopus fan circuit. 

@mvdveer correct me if I'm wrong a ground sent to the fan is what turns it on, correct? If so could be a ground source in the tool head PCB.

Sounds good, I'll give that a shot today once I get home.  I have had a few people mention it could be the Octopus board, but I hate to buy another one and that's not it.. but then again getting it from Amazon would be helpful.  I'll post back later today.  Just odd everything worked great up until this, but then again it's just like working with PC's, sometimes random crap happens

[mvdveer]

8 hours ago, nickpeck47 said:

I have had a few people mention it could be the Octopus board

would be strange, as you have already tried a different fan input if I read your first post correctly. Just make sure your polarity is correct on the octopus side

[nickpeck47]

Yes, it's plugged in correctly.  I removed the PCF cable underskirt from the LDO PCB to the Octopus and the fan still turns on and stays on...  Everything on the SB works fine, the LEDS light up, the hot end fan only turns on when it's supposed to, everything heats ok...  No wires are pinched, I rechecked all ground and connections and everything looks fine.  

I was wondering if the Octopus has a problem, but I don't even have the fan plugged into anything underskirt and it's still turning on.  Think the fan is screwed up?  But something has to be turning it on, right?  I don't have an extra blower fan, so I guess I can order one to test it (won't hurt to have extras anyways).

I have around 60hrs printing on it the past week perfectly, then the other day I turned it on to start printing and the part fan started doing this.  The only thing I did was update some of the software packages from the dashboard, but I'm pretty sure it was doing this before updating, and before that I made no changes as it was printing fine.

So odd lol.

3 hours ago, mvdveer said:

would be strange, as you have already tried a different fan input if I read your first post correctly. Just make sure your polarity is correct on the octopus side

 

Edited May 20, 2023 by nickpeck47

[nickpeck47]

17 hours ago, mvdveer said:

would be strange, as you have already tried a different fan input if I read your first post correctly. Just make sure your polarity is correct on the octopus side

I had someone mention that there is a possible short somewhere?  While everything looks ok, once it's done w/ a test print I'll unplug my TAP, maybe a crimp in there isn't solid or something, the TAP works perfectly fine, but maybe the fan isn't liking it possibly.

[nickpeck47]

Well, I looked everywhere and couldn't come with anything.  However, I decided to pull the fan out again and pull the sticker back and noticed this... Could be the issue possibly, I have to order another fan to know for sure.

[PFarm]

Do you have a multi-meter? If so check the fan port that your fan is plugged into on the Octopus board, if you can read 24V. on the meter then that port is defective

 

Edited May 21, 2023 by PFarm

[nickpeck47]

3 hours ago, PFarm said:

Do you have a multi-meter? If so check the fan port that your fan is plugged into on the Octopus board, if you can read 24V. on the meter then that port that port is defective

I ordered the new fans and I'll move it over to one of the open ports and dodge that one for now.  I may grab another Octopus board to sit on in case.  I'll update once the new fans show up.  Thanks for the help, its appreciated.

[nickpeck47]

Just a quick update.  So, since that fan didn't look great (even though it worked) I replaced it with a better one, but once I installed it, the same thing lol.  So, just by chance I'm building another SB tool head and I was able to find the LDO SB PCB kit, so I bought it and figured, let me swap the toolhead PCB and see....  Yup, that was it.  So thankfully it wasn't an issue anywhere else as it's now working properly.

Thanks for all the help you guys, much appreciated.