Extruder stepper not working

Hi
I have been trying to fix this for months, so now I have resorted to posting it here for some help.

I have a homebuild printer, with Ramps 1.4, A4988 drivers. I am using Repetier to manually drive my machine while I sort out the kinks. I am jumpered for 1/16, I have tried 1/8 too.

Everything now works except the extruder stepper. (including thermister)

I am using the Repetier firmware, I have tried the factory setting, I even mirrored the settings from my X axis, to no avail. (The extruder hob is the same diameter as my pulleys)
I even tried youtubing other people setting up their machines and copied their settings.

I have replaced drivers, checked wiring and the motor.

I have moved wiring, drivers and jumpers to E1, with the relevant details added to the firmware settings to no avail.

If I set the X axis to work on the Extruder stepper output the stepper motor works. The driver, wiring and motor are obviously not the problem.

When I click the extruder control on my computer I get the same flickers as I do when I actuate other axises, just no motion.

I have changed resolution to many settings - from 44 to 650 with no avail.

I have changed acceleration from 5000 to 200, and 100 with no success.

I have tried Invert enable signal

Can anyone please tell me what may be going wrong?

Edited 3 time(s). Last edit at 12/13/2016 11:09AM by mericanpi.

Are you heating the extruder to temp befor you try to extrude filament, the firmware inhibits cold extrusion attempts.

Is the hotend hot? The extruder won't run if the hotend is below a minimum safety temperature unless you send M302 first.

OH WHAT!!! C"MON!!!!
Noob error of the century. Wish that was documented somewhere, would have been good information to have.

Thanks to you all!!! I fired it up this morning, reflashed the firmware to factory resolution and it worked first time.

There's a heap of time I'll never get back

Thank you so much !!!

Glad it's up and going - now the real fun starts! Welcome to the forum