Hi, I'm from Argentina and I'm using a translator. I have an ipresora 3D Delta with Arduino Mega 2560 and Ramp 1.4. It happens that the fan of layer of the printer works with the tension that provides pin 9 of 5V but it happens that off I have 0V (correct) but ignition I continue measuring 0V; never get 5 V to pin 9. Any suggestions. Thank you
Post the code you're using and either a picture or a diagram of how you have it wired.
What controller firmware are you using? Marlin?
Hi,
Welcome to the forum.
Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html . Then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.
Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
Thanks.. Tom... 
I am using Marlin-bug-fix 1.1.x
The wiring of the Ramps is as indicated by the jpg and the endstop are in the position of xyz max
The layer fan is controlled by PWM so unless the firmware turns it on you will see 0V at pin 9. Can you manually control the layer fan with the printer control or through software? I think Repetier lets you control the layer fan from its control panel maybe other programs do as well.
Yes, correct, the PWM in pin 9 controls the layer fan. I have attached two Marlin files so that someone else, other than me, can see if it is activated, I do not see the error.
Can you manually control the layer fan with the printer control or through software?
Repetier software
Solved.
Thanks to those who contributed time and ideas. After a long time and think that the problem was in the plate, I changed the pin assignment in the firmware and I could see that the situation worsened because in addition to the fan, stopped heating the hotend.
I downloaded the latest version of Marlin again and after setting it up, yes, the layer fan works.
Thanks again.