Some Moto Monster help

I am currently testing out how a 2 DOF setup could work for me. Therefore a bought 2 wiper motors and a "Moto Monster Shield". The Arduino parts I had already, as I am doing other stuff with it.

After putting the peaces tohether I have the following situation.

The chip of Motor 1 on the MM is getting really hot, very quickly but the motor is not moving. The second motor is moving as expected. I first used a sample code (from SparkFun) which just moves the motor in one direction and then it is changing. As I said motor 2 is working, but motor 1 not. The chip for motor 1 is getting directly hot and the little lamps indicating the direction are not lighning. For Motor 2 everyting looks ok.

Does anybody know what could be the reason?

try to swap motors and tell us

Hi, I tried this already. The same motor works fine on A2/B2 but nothing on A1/B1. Nevertheless I would expect the little lights to change if the chip is switching direction, what he is doing for A2/B2. The chip for A1/B1 is just getting hot.

I also removed the arduino and just put power to MM (so no controlling via arduino). Again chip 1 gets hot, but not chip 2.

hi Christoph, I can't help you, wish I could, but I can't. I was wondering where you got the mm from. Is it a spark4fun or a cheaper one? I need to order a couple, and I'm trying to justify the price difference vs quality. I'm sure it's been talked about on here, but since this is a new thread I would like to follow the updates. thank you

@noorbeast: I will check this, thanks for the hint. But as A2/B2 works fine with the motor, I am not sure if this is the reason. Also as the situation doesn't change if I haven't any motor connected to it.

@dberg1: I bought it in GB via eBay. On the backside it is written Sparkfun. The price was something like 20 GBP.

share some pictures!

what's about your pots?
because for example if only one pot is wired, the MM doesn't work properly.

Uups. And here it comes the noob question: I haven't put any pot until now. I just wanted to test the MM
and thought the pot I will only need for positioning the motors. So do I have to add them always?

P.S. I will make some pictures as soon as I had a look with my brother. He far more experienced with this kind
of eletronik stuff

I would say that without them, the state of the pins is fluctuating...

for example, if you wire only one pot: both motors are turning accordingly.

hi guys i have some questions, i bought motoshield from Ebay.com and i connected to Arduino Uno and motoshield was heating when it connected power not connect load (motor). i put aliminum heat sink.
i think may be motomonster broken. this motoshield was working just 0ne direction and too much heating. how i check operation that motoshield

@Christoph Grund Sounds like you have fried your moto monster. Not connecting pot to shaft of motor or not connecting pot at all = dead motomonster. The chip heating up but not doing anything generally means that the chip has fried, gone short circuit and is now a small space heater. If there is no PWM signal on the line to the motor driver chip, the chip will fully turn on and draw maximum current from your power supply. It does this because whilst the motor is not moving it is considered and electrical short circuit. PWM sort of "soft starts" the motor and reduces the current draw of the motor. If your power supply is able to supply more current than the chip can handle then say bye bye to the chip.

Source: Me blowing up my motomonster doing the exact same thing as described.

Edit
For the above: Isn't the pot meant to be connected to the arduino? Using the shield in unintended ways could damage the unit and thus is hard to troubleshoot because damage could have been done to the unit because of incorrect connections rather than a faulty unit. Could you sketch up a circuit diagram of all of the connections including what code you are using?