Cooling fan turns on and off when wiggling main wire bundle
Hi all,
This printer has been great for years with very little problems. Recently, the printer was jarred hard and has developed the following problem.
The cooling fan cycles on and off while printing. I discovered this is due to a loose wire somewhere since wiggling the main wire bundle from the extruder assembly will cause the fan to cycle on and off. I suspect a loose wire. The printer appears to function normally otherwise.
Can I get some instructions on how to troubleshoot further? Does this sound like a loose fan wire? Or could there be a problem with a heat sensor? Any help or guidance would be greatly appreciated. I'm fairly comfortable tinkering, but don't like to do so blindly. Thank you!
RE: Cooling fan turns on and off when wiggling main wire bundle
If the cooling fan turns off while printing when it should otherwise be on, I’d suspect an intermittent/ broken fan wire. I’d diagnose by first verifying this as follows:
Because it was jarred hard, I’d initially check that the fan connector was not partially knocked loose on the Einsy board.
First I’d make sure that it is not a bad thermistor (temperature sensor) by checking on the LCD screen for an expected and consistent hot end temperature.
Second I’d separate the fan wires from the bundle of wires between the Einsy and the hotend up to the zip ties on the hot end. I wouldn’t cut the zip ties just yet.
Third I’d start the fan from the control panel and then wiggle the fan wires attempting to get the fan to stutter or stop entirely. If it does, we’ve found the problem: bad fan wires. You can then either splice in new wires as a temporary fix or just wait until you obtain a replacement fan.
If the fan runs smoothly even as you wiggle the wires then we’re back to square one having [most likely] eliminated the fan wires as cause. At this point more brainstorming would be needed to suggest another possible failure mode to test. Let us know what you find out.
DJ
RE: Cooling fan turns on and off when wiggling main wire bundle
Sorry, I meant Rambo board as this is the MK2 we’re talking about.
DJ