Three pin mechanical endstops I've just recently purchased a set of three pin mechanical endstop switches and I've just wired them up to my ramps 1.4 board. If I'm correct I've wired them to the pins labelled x y z where I've connected signal to the top pin, ground to the middle and vcc to the bottom. I'm running sprinter on printerface and when I'm connected the leds on the endstops never light and they make no difference when I'm jogging or printing. Please could someone advise what might be wrong? Thank you very much. Ben https://reprap.org/forum/read.php?4,457212,457212#msg-457212 Mon, 20 Apr 2026 14:52:48 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?4,457212,457564#msg-457564 Re: Three pin mechanical endstops https://reprap.org/forum/read.php?4,457212,457564#msg-457564
The bottom (+) pins in the end stop area of the RAMPS board are connected to the 5 volt VCC connection to the Arduino and the middle pin, the middle (-) pins are connected to the GND bus, and the top (S) pins are connected to the digital inputs on the Arduino as below:

X-MIN: pin D3
X-MAX: pin D2
Y-MIN: pin D14
Y-MAX: pin D15
Z-MIN: pin D18
Z-MAX: pin D19

These pins are configured in Marlin (in pins.h) but the 5V and GND are hardware-connected and are not configurable.

I would disconnect the switch-end of the end stop wiring and check for voltage between the 5V and GND pins in the connector. If there is no voltage when the Arduino is on, the RAMPS board is probably damaged.]]> MindRealm Reprappers Mon, 19 Jan 2015 15:10:21 -0500 https://reprap.org/forum/read.php?4,457212,457249#msg-457249 Re: Three pin mechanical endstops https://reprap.org/forum/read.php?4,457212,457249#msg-457249 Ben.folkes Reprappers Sun, 18 Jan 2015 23:10:40 -0500 https://reprap.org/forum/read.php?4,457212,457248#msg-457248 Re: Three pin mechanical endstops https://reprap.org/forum/read.php?4,457212,457248#msg-457248
Looking at this picture of the RAMPS, the endstop connectors are on the upper left. The top row of pins is the signal, the center row is the ground, the bottom row is the positive voltage. You need to connect like pins together.

Moving from left to right, the columns of pins are X Min, X Max, Y Min, Y Max, Z Min, and Z max.]]> jbernardis Reprappers Sun, 18 Jan 2015 23:02:51 -0500 https://reprap.org/forum/read.php?4,457212,457212#msg-457212 Three pin mechanical endstops https://reprap.org/forum/read.php?4,457212,457212#msg-457212 Thank you very much.
Ben]]> Ben.folkes Reprappers Sun, 18 Jan 2015 19:04:20 -0500