Hot end stops heating as soon as printing starts

Hi! I am a noob when it comes to 3d printing, I just got my machine last week, it is a Prusa I4 by PanTech (or i3+ or whatever...) assembly was pretty straightforward, it appeared everything was working well, the temps came up using the preheat routine in the controller (marlin v1) but as soon as the head moves the heat turns off and the nozzle rapidly cools and cannot extrude... I am putting my G code on an SD card, using repetier and cura, when I look through it the nozzle temp is set (no wait M104) i thought there was a gcode for autotemp, but i cant find it. any ideas or helpful! thanks!

Open your g code file with notepad or wordpad and check the temperature set in the file, you might not be setting the temperature right in the slicer.

Will the printer try to keep printing the file or stops immediately?

the temp set with m104 s190 (as far as I am thinking) is it elsewhere? the header is as follows:

;Generated with Cura_SteamEngine 15.01
; Default start code
G28 ; Home extruder
M107 ; Turn off fan
G90 ; Absolute positioning
M82 ; Extruder in absolute mode
M104 s190
G28 x y z
;Layer count: 32
;LAYER:0
M107
G0 F9000 X62.100 Y96.310 Z0.300

I was thinking I should go through my start up, I prewarm everything using the preheat ABS routine, when that is complete I print from the SD card, at that point the heat cuts out, everything else keeps going (XYZE) but i kill it pretty quick...

Loose wire (or near-broken wire) to the heater? Maybe it connects when the printer is in the home position but disconnects when the head moves? Hopefully you have the wires rigidly attached to the head so that when it moves, there's no movement of wires near the head?

Its pretty mechanically secure, it stays at temp when I move the head in manual mode (and extrude manually), the machine just seems to work in manual mode, when i try to run gcode, the heat turns off

you seem to be missing a m109 instruction that tells it to wait for extruder to reach temp

eg.

;Generated with Cura_SteamEngine 15.01
; Default start code
G28 ; Home extruder
G1 Z15 F100
M107 ; Turn off fan
G90 ; Absolute positioning
M82 ; Extruder in absolute mode
M190 S50
; Activate all used extruder
M104 T0 S200
G92 E0 ; Reset extruder position
; Wait for all used extruders to reach temperature
M109 T0 S200 <<<<<<<<<<<<<here
;Layer count: 35
;LAYER:0
M107
G0 F9000 X77.403 Y80.819 Z0.300