Geeetech

GT2560A, Mega2560+Ramps1.4., MK8 hot end, Mk2A heatbed. Power supply as provided DC12v/15Amp

Everything was working fine until yesterday. The hotbed would not heat up. The screen is registering the room temperature for both the hotend and the heatbed indicating that the themistor is working. When my husband tried to test the heatbed the indicator light on the board is on, but he is not getting any readings from the contacts on the heatbed. On the board it looks like where the hotbed connects, it looks like it may have started overheating, the plug is warped but not burnt. There is signs of overheating as the green plug started to melt but did not burn. The Hotend still functions fine.

The question is how can I specifically test to confirm whether the heatbed or the board is faulty. Please be specific and with pictures if possible. We have already ordered a new and stronger power supply.

how about the heat bed resistance? you can check this link:
http://www.geeetech.com/forum/viewtopic ... 19&t=17039

So through checking many of the posts, we figured out how to test everything and it turns out the problem is two things. First the problem is the plug on the board where the heatbed plugs in, started to overheat when trying to heat the bed to 110 for ABS printing.

The resistance on the bed is perfect at about 1.2 ohms. It appears that essentiallly, the power supply for this system is too weak, and when trying to heat the bed for ABS it draws too much power into the plug on the board which warped and started to overheat, possible partly also due to the weight of the wire pulling down on the plug which we have now supported with a cable tie to give it lateral support and another cable tie so the wire doesn't move when the bed moves. Luckily nothing burned out and we have ordered a new power supply. We would like to find the socket that goes on the board so we can replace it to ensure it fits snuggly.

This is a very good product but it is let down by the cheap power supply and our other complaint is the poor manufacture of the bearings. The longer bearings we received, one of them all the bearings fell out which we had to repack and regrease, bearings shouldn't come without at least a minimal amount of grease to actually hold the ball bearings in, you need to check your manufacturer of these bearings.

You should also include a better power supply, the difference in price wouldn't be much and I am sure that people wouldn't complain on a small price increase for a better power supply.

sorry for your trouble! you can find the plug here:
http://www.ebay.com/itm/10-Pcs-5-08mm-P ... 1201924630