Asking for some help

So I've been trying to get my Rostock printer to work, and have not had much success. Sorry if my questions are noob-y, I'm still pretty new here. So then,

1.) Thermistor is not working. On Repetier Host, it says the thermistor is giving a value of -59 degrees. This is most likely a wiring problem, but I don't know what it can be, both wires are insulated and shouldn't be touching each other.

2.) Repetier Host's manual control does not seem to work too well. When told to home, the hotend rises 10 cm or so and stops. The Host then says that the position is X=0 Y=0 Z=(maximum height), even though the hotend has not gone to the center or the top. Also, when the endstops at the top are triggered, not much happens except for the carriages (not sure if right term, it's the things that go up and down the rails) jamming into them and bouncing back down with a sound that is somewhat worrying. I've checked, the endstops are working properly. Also, the extruder motor does not respond to commands, but appears to be working anyway.

I'm sure most of this is due to the firmware being bad or incorrectly set up. I'm using Repetier firmware for this. Any help is greatly appreciated.

There could be a break in the wiring of your thermistor. Unplug it from the board and use a multimeter to test its resistance. I want to say it should be either 10k or 100k when cool, but it depends on the type of thermistor you have. Also double check to make sure you have it plugged in correctly, perhaps you used T1 instead of T0 or something similar. Happens to us all.

Been awhile, but I think issuing an M114 or M119 will return the current status of your end stops. It is possible one or more of them might be configured wrong in the firmware, so when you got to home the effector plate, it thinks it is already homed. Again, make sure that you are using the Z-max endstop pins, not the Z-min. That is a mistake I have made a few times.

You might also consider reviewing the information that came with your printer. Things like the type of thermistor being used or the number of teeth on your belt pulley's. Attaching your Config.h file might also help, though I wouldn't paste it directly into a post.

I don't have much time to check things right now, so I'll respond in regards to the endstops. I checked, the outputs should be correct. High when pressed and low when not pressed. I think the pins are in the right places, but I will need to check. Regarding the printer, it was not bought from a kit, rather assembled from scratch. I bought a J-Head hotend, but it did not specify the type of thermistor that came with it. I'll need to check most things, but thank you for your help.

Sorry for the gaps in time. I've checked the thermistor, and turns out the weld connecting it to the RAMPS board broke. Whoops.

I've checked with the endstops, looks like you were right. It was the opposite of what i previously said. M119 returns H for all, and M114 returns 0 for all. Unfortunately, the original Config.h file was lost, and I've tried to make a new one, but it gives me error messages, all related to fastio.h and _WRITE.