My pololu 3pi robot is not turning on

I am very new in robot making, and just started few months back. So, please forgive me if I am too vague explaining the problem.

First let me explain what I did,
I connected(soldered) wares to the “charge” port of my 3pi robot, so I can use the on-board charging mechanism to charge my DuraTrax AAA-750 NiMH 1.2V 750mAh battery using Tower Hobbies AC/DC digital peak charger. Every thing went perfectly fine, and I was able to charge the battery properly. But after charging when I was taking out the wares from the chargers on the body socket, accidentally the naked ends touched each other… Right away I saw some smoke come out from the robot circuit and I cant turn on the robot any more.

Can some one suggest me on which direction I should look for the problem? Or it is hopeless and go buy a new one :confused:

I used a multimeter to check continuity, and I can see power is coming from the battery and to the push button, except I am not registering anything against the power button. But then I am not sure thats the way I should approach the problem.

Thanks in advance,


You should be able to look at the PCB traces on the bottom side of the board. One of them probably melted when you shorted out the battery. Can you tell which one it is? If you can find it and post a picture, we can give you some suggestions for how to fix it.

- Jan

here are the screen shots…
apparently it looks like there is no trace of melting… is there?

Yeah, I don’t see anything there. Can you see the battery voltage on the battery charging port?

- Jan

Hey Jan, first thanks for helping me out here…

I am reading zero volt across the battery charging port and my battery is connected.


There aren’t that many traces between the battery holders and the charging port. Can you verify that you have about 3V across each battery holder, and then 6V across the two in series? If that checks out, see if the negative side is connected to ground, and see if the positive side (of the 6V) is connected to the charging port.

- Jan

guess what ? !!! :smiley:

the bat holder springs were loose… thanks for the diagnostics Jan