I got a kit and assembled it. Printer did it job for a while and then i wanted to remove fan to assemble it another way, but forgot to unplug the cables so printer was on whet i tried to unsolder the wire. I touched the wire with soldering iron and saw little flash. I turned of all immediately. Then I put all together but repetier host now tells on connection try only - The port com3 does not exist.
I checked the usb in front of the pc where it was plugged and seams they are dead. So I plugged the wire in another usb ports directly on mother borad. Now I see the two led lights are on one green and one red constantly. I checked the power supply with multimeter and it seems like working. However repetier is still telling the same error. What can I do in this situation? and what it means - two constant led lights?
check the Hardware Manager - it is possible that a different COM port number is assigned when the printer is connected to a different socket. When the two USB leds on the board (green and red, LD5 and LD6) light up, then the connection between board (at leat the USB chip) and the PC should be established, and the COM port visible.
However, both LEDs should turn dark and only flash when data is transfered once the board is fully powered, so if they remain lit when the main power is on, then something is wrong. If that is the case, check whether the voltages coming from the power supply are ok (15 V on the screw terminal). Also, there is a labeled point for measuring 5 V in the upper right corner, where the connector for the LCD module can be soldered. This should - of course - have 5 V against GND or the “-” screw terminal.
I checked the hardware manager but i do not see USB serial port. When I plug USB cable both led5 and 6 are on, but after plugin power supply only red is on. I checked the voltage on screw terminal and it is 15V and in the upper right corner is 5V . When I press restart button another green led is blinks and disappears. but still is no USB serial port in the device manager. I tried different PC and different USB cable also with windows 7 but had the same result.
What else can I do?
unfortunately, it seems that there’s indeed something wrong with your board; most likely the USB chip (FT232RL) is damaged.
There are adapter cables (USB to UART) available that contain the same chip, but the board does not have a prepared pin header for such a cable, so it would require a lot of rather delicate soldering and circuit-tweaking to connect such a cable. Controlling the printer via a LCD module could work if firmware “V2” is already loaded, otherwise, you’d need the USB connection for changing the firmware, i.e. a chicken-and-egg problem, or later firmware updates as well. Additionally, there’s no guarantee that nothing else on the board is broken.
If you know your way around electronics and like to tinker, you could try to get it running again like mentioned, otherwise, I’m afraid you won’t get around investing in a new controller board.
Thank You for Your help. Do You know is it now possible to check the firmware version, may be some Repetier log files?
no, not without communicating with the board.
According to Velleman, the new boards are loaded with the “V2” firmware from the beginning, but I cannot say whether your printer is one of those “new” ones or not.