Hello. New member. And problem with the battery

Hello, my son got to third grade, and I got a used IQ Super Kit to start playing with it, even though it looks like he’s not ready for it yet.
We’ve been doing blocky programming with a Lego WeDo robotic set and a Dash robot, so I wanted to have the IQ set for when he’s ready for it.

As said, the set is used, and the battery seems to be dead. When I put it on the charger, I get the blinking red light and it doesn’t get charged.
I tested the charger it with a multimeter and it reads 800mV DC so the charger seems to be good.

So I couldn’t test yet the brain, motors, sensors, ecc.

Looking forward to start building.


First, the battery is a 6-cell NiMH battery, so 800 mV for the entire battery is very badly discharged. Normally, you don’t want to see much below 1 volt per cell, so under 6 volts is really dead.

Try following the instructions in https://kb.vex.com/hc/en-us/articles/360035590652-Battery-Troubleshoot-Electronics-VEX-IQ. Worst case, you can buy another battery at https://www.vexrobotics.com/228-2604.html.

Best of luck and hope your son enjoys it.


Amazing! I had kept the battery on the charger for several hours just in case, but the red light kept blinking and the battery wouldn’t turn on the brain.

The trick of the wheel brought it back to life. While twisting the wheel, the screen on the brain would do some blinks.
After a minute or two, I put the battery right away on the charger, and this time the red light was solid. In a couple of hours it turned green. Now the brain shows the battery status at 8V and 92% of charging capacity.

The person that sold me the kit said that her son used it once or twice and then it sat on the closet for two years before she decided to sell it. So the battery is supposed to have some years of shelf life but not really many charge cycles. So hopefully it has some life left.

I wonder what the wheel twisting do to bring the battery back to life like that.

Anyways, thanks again @teresajude


A DC motor is reversable to act as a generator. The “smart” circuitry in the charger won’t respond to a battery with too low a voltage, so you make a dumb charger with the generator to bring it to a voltage level the smart charger will recognize.


No wonder why the screen would light up when I turned the motors super quickly

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Happy fathers day!‎‎‎‎‎


Thanks! :slight_smile:

We built the base of the clawbot today and tested all the sensor and motors. Everything works fine.

The battery charge didn’t last long. I guess it’s not in the best shape possible, but it’s good for the moment. Eventually will get a new one.

A better organizer seems to be a must too.

Good thing is the boys like it so far, so they may have robotic side in them. My 8 years old got into the robotic program at school, and they use the VEX IQ system, so I wanted to have it at home to give him an extra motivation.



Here’s a Superkit organizer: