# Dual Switching Hotend - not activating Servo **URL:** \ **Category:** General Discussion\ **Created:** [December 8, 2024, 2:24am UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534 "2024-12-08T02:24:58Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Jimmy\_the\_Cow](https://avatars.discourse-cdn.com/v4/letter/j/48db29/32.png) [@Jimmy\_the\_Cow](https://klipper.discourse.group/u/Jimmy_the_Cow)\ **Post date:** [December 8, 2024, 2:24am UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/1 "2024-12-08T02:24:58Z")
### Basic Information: Printer Model: Proforge 3.5 MCU / Printerboard: BTT SKR-2 Host / SBC Ubuntu on NUC Celeron [klippy.log](https://klipper.discourse.group/uploads/short-url/t82ZSCM4IdTDj4ZPQe4DkGyMo9I.log) (5.7 MB) klippy.log _Fill out above information and_ **_in all cases attach your_ `klippy.log` _file_** (use zip to compress it, if too big). _Pasting your_ `printer.cfg` _is **not** needed_ _ **Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there** _ ### Describe your issue: … Switching from a Direct Extruder setup to the official Proforge dual hotend kit. [This is the guide I followed.](https://makertech-3d.dozuki.com/c/Proforge_3_3D_Printer) [Here is the Klipper printer.cfg I am basing mine on](https://github.com/Makertech3D/Proforge-3.5/blob/main/Klipper%20Config%20Files/printer.cfg) Of course my printer .cfg and macros look different because I am using a BTT Eddy as well (that works fine) When I send the command to the arm servo, I get no activity at all. I do not get any errors, just no movement. I have tested with a second servo with no results, and can verify 5v on center pin. I have it plugged into “Servo” according to the github diagram. Everything else works perfect, already did a PID tune and everything. Just cant get the servo to move at all. Attached is my printer.cfg, macro, and variables. Thank you for reading my question. [config.zip](https://klipper.discourse.group/uploads/short-url/xYLXxgLbfXGRWZJrJGY5r5mKwwq.zip) (62.3 KB) ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [December 8, 2024, 11:45am UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/2 "2024-12-08T11:45:41Z")
```auto [gcode_macro ARM_INSTALL] gcode = SET_PIN PIN=servo_power VALUE=1 SET_SERVO SERVO=extruder ANGLE=90 [gcode_macro SERVO_OFF] gcode = SET_PIN PIN=servo_power VALUE=0 [gcode_macro ARM_POSITION] gcode = SET_PIN PIN=servo_power VALUE=1 {% set serv_angle=params.A|default(0)|float %} SET_SERVO SERVO=extruder ANGLE={serv_angle} G4 P1500 SET_PIN PIN=servo_power VALUE=0 [servo extruder] pin = PE5 initial_angle = 165 maximum_servo_angle = 180 minimum_pulse_width = 0.0004 maximum_pulse_width = 0.0024 [output_pin servo_power] pin = PE6 pwm = False ``` I would simplify the setup to only the servo and then test it. The approach with the power pin seems incorrect, as this is a control pin at 3V3 and not a power supply pin. ---
**Author:** ![Jimmy\_the\_Cow](https://avatars.discourse-cdn.com/v4/letter/j/48db29/32.png) [@Jimmy\_the\_Cow](https://klipper.discourse.group/u/Jimmy_the_Cow)\ **Post date:** [December 8, 2024, 6:06pm UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/3 "2024-12-08T18:06:43Z")
Thank you for the reply, and the help. I looked over the commented code you left, and I don’t see anything different in the code you posted and the code I already have. Is there something else I am missing? Again thank you for the reply, I have 2 other servos and plan to plug them straight into the board to confirm its not a cable issue as well. ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [December 8, 2024, 7:11pm UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/4 "2024-12-08T19:11:08Z")
Sorry, apparently I was not very clear. The code above is exactly your settings (spread all over the place in the config) and I just copied it together to highlight: > [@Sineos](#): > > I would simplify the setup to only the servo and then test it. The approach with the power pin seems incorrect, as this is a control pin at 3V3 and not a power supply pin. ---
**Author:** ![Jimmy\_the\_Cow](https://avatars.discourse-cdn.com/v4/letter/j/48db29/32.png) [@Jimmy\_the\_Cow](https://klipper.discourse.group/u/Jimmy_the_Cow)\ **Post date:** [December 8, 2024, 8:01pm UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/5 "2024-12-08T20:01:53Z")
Hahaha thank you! Okay, I see what you mean. Teach a man to fish… Your issue lies here… Thank you for the nudge, I’ll look into testing just the servo itself if possible and report back later with my findings. Thank you again for your patience and guidance. ---
**Author:** ![Jimmy\_the\_Cow](https://avatars.discourse-cdn.com/v4/letter/j/48db29/32.png) [@Jimmy\_the\_Cow](https://klipper.discourse.group/u/Jimmy_the_Cow)\ **Post date:** [December 16, 2024, 12:54am UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/6 "2024-12-16T00:54:49Z")
Found my Solution! It was a dead Servo!! I either killed it while trying to figure out the klipper code, or it was dead on arrival. Either way, I had 2 spares and when I plugged in a spare. it hommed itself and were cooking!! Thank you for those that read my post. ---
**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/klipper/original/1X/64419bf2aac6639e6ef5cef200dcd456b0a01ac3.png) [@system](https://klipper.discourse.group/u/system)\ **Post date:** [January 15, 2025, 10:54am UTC](https://klipper.discourse.group/t/dual-switching-hotend-not-activating-servo/20534/7 "2025-01-15T10:54:51Z")
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