While under normal operation (not a competition, just working on timing for autonomous programming) one of the joysticks stopped communicating and then the other;lots of connection problems, we turned it on and off, got it to work then it stopped and so on. We had recently changed the battery. Noticed a burning smell so we looked close and saw a wisp of smoke coming out of the USB area of the cortex. Unplugged everything, felt everything except the motor controllers (didn’t think to check those until later, looking through forum posts and I see that’s a common problem) nothing I felt was warm. Opened up the cortex, an integrated circuit next to the motor plugs (can’t see an id number on it but it is next to r19, r22, c27, c29) is black. Going to try to insert a photo below.
Questions : what to do next? Throw out the cortex, test the motor controllers (how does one test those or find out they are bad?) I’m scared to plug in another cortex and kill it, that’ll be the end of my budget. The cortex has been through 2 competition seasons, is there a lifetime to them? Any chance to salvage the cortex at least for a non-competition robot to use as a demo?
Thanks for taking the time to report this problem.
It looks like you overheated port# 1 in your Cortex, what kind of motor were you using on port# 1 at the time of the incident?
Please note that your Cortex should be fully functional, with the exception of that specific motor port. That means you can definitely use it for demo & practice purposes.
Warranty for our products can be found here. If you have a VEX order number we can schedule a return and analyse the unit in more detail, at that point we can let you know if the unit can be restored back to the original state (repair fee may apply).
Ah, good news, thanks! The motor in that port was a 269 connected with a brand new 2 wire 24" extension (so no motor controller). It powers a spinning intake. Didn’t think it was worked hard at all… any idea why that might’ve burnt out? The motor wasn’t hot at all.
Please inspect the motor for shorts, make sure the wire insulation is in good shape. Stalling the motor could also cause such problem.
Thanks, Eli - just a visual inspection for breaks, or is there something else I should be looking for or testing?
I recommend a visual inspection.
If the insulation is in good shape, then most likely the motor was being stalled.