I have purchased the undermentioned robot chassis with DC motors supported with plastic gears from a local store. There is a 3A battery holder and when I connect robot to that and put it on the ground both the motors working fine and smooth. But when I connect the L298N motor controller which was made by myself and tested with proteus, only one motor is working. When I switch the wires of both motors, still the motor which worked before is working and the other motor never runs unless I manually give a little rotation to the wheel.
I use a PIC18F4431 to control the motor controller and tried USB power and a 5V regulator created by myself and the result is the same in both occasions. What could be the issue here? If I tried oiling the malfunctioning motor will it work? I heard one of my friends having the same issue, one motor is not working. But both motors work with just two pen torch batteries and can't think of a valid reason that the motor is faulty. May be my motor controller? But when I swap the wires from faulty to the working one, the working one still works as I've mentioned above.