Motors and batteries going bad

We have the first Vex 5 super kits that were available and they have been used five semesters. About 8 motors have quit working in the last month (won’t turn when programmed, run by controller, or tested on brain) and four batteries won’t charge or allow reset/updating. When the power test button is pushed, four green lights will illuminate and immediately a red light will start blinking afterward. Are there known issues?

I know about the motor issues and my school has just purchased more motors. As for the battery issue, we have not had that problem.

Two of my school’s motors are dead, and one makes a grinding sound. One brain port is dead. Once we let a battery charge for months and it was weird, we just reset it.

We bought our first set of V5’s pretty early too. We have had similar battery issues. Every so often, some of the batteries will display the “Blinking Light 'O Death.”
When it does so, put a paperclip or similar into the hole on the battery to reset it. It will usually work again (albeit sometimes temporarily until you get the light again)

We have only a few motors that have failed over the years since the V5 came out. Less than 5-6 motors out of our clubs at least 30-40 motors. The larger issue we have had is that of Brain ports dying. The motor ports can blow out due to field static
Make sure you buy anti-static spray for your fields

Also, the Micro USB port on the brains, especially the early ones is garbage. I know this isn’t what you originally posted about, but I’m guessing you aren’t doing these if the V5’s haven’t been used in 2 years. There are a number of things you can do to mitigate the risk, however. I would strongly recommend doing all of the following:

1. Use wireless downloading. Connect your programming computer to the controller, rather than the brain. Make sure the brain and controller are connected (wirelessly via the radio) and you should be able to download code to the brain. (I have only done this with VEXcode.)
2. Use magnetic cables at all times. Buy micro USB cables with a magnetic end that you leave in the brain and/or controller. These are (similar to) the ones my team uses. I would recommend getting ones in which the small connector that you leave in the brain has no recesses or concavities. In a VRC robot, these will get clogged with metal shavings very quickly which will prevent the port from working properly. The ones I linked above are fully convex.
3. NEVER PLUG ANYTHING INTO THE BRAIN Protect the brain’s micro USB port at all costs. I’m assuming from your post that you are a teacher or coach, so never let students remove the magnetic pieces if at all possible. These ports are incredibly cheaply made and break very easily. If you have used the brains at all, they are very likely already on their way out, especially being so old.
4. RMA Brains and/or motors Most of our original brains had several (sometimes up to 10) dead ports each. We sent the worst ones back to Vex. The recently purchased ones were free and the older ones cost $60. That is well worth it for a $250 Brain that is out of stock.
Hope this helps. Feel free to respond to this with any questions.


I was onboard (and bought a dozen high-quality sets for our teams) with this one until metal shavings from robot construction shorted them out. Now, I would highly recommend the Robosource adapter:

You leave the short adapter connected at all times, and just use the big USB port.


While I can see that could be an issue, I have never had anything like that happen. I actually never use the brain port. I always download code wirelessly.

Depending on how much cutting and fab (especially grinding) the team(s) do, it might not be a problem. Our U-team caught it first (they do the most custom fab, but the metal dust ends up all over the shop), and I immediately recalled all the cables from the other teams so as to not have the issue spread.