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I can't control the Trim servo

Alvaro Lopez

I'm New Here
Im building a RV-12iS with Garmin G3X GDU 460, without AP.

I want to know why I can't control the servo with the joystick buttons. I double checked the sub D connectors and i made it electrical test (all the wires are well crimped and routed).
The servo does work. I removed the servo from the tailcone and powered it with a battery and it worked. It moved both ways (retracted and extended).
I noticed that the remaning buttons (PTT, ACTIVE STDBY) on the joystick works.
 
Are the servos connected directly to the stick or are you using something like a VPX for power distribution?
 
You can’t use the joystick buttons directly. You need a reversing relay or similar (non coolie) switch. Both motor leads have to be switched. The coolie hat switches are just SPST momentary type.
Google “motor reversing relay” for a diagram.
 
Im building a RV-12iS with Garmin G3X GDU 460, without AP.

I want to know why I can't control the servo with the joystick buttons. I double checked the sub D connectors and i made it electrical test (all the wires are well crimped and routed).
The servo does work. I removed the servo from the tailcone and powered it with a battery and it worked. It moved both ways (retracted and extended).
I noticed that the remaning buttons (PTT, ACTIVE STDBY) on the joystick works.

It is difficult to diagnose the problem from afar without more detailed information.

What stick do you have? Does it have a coolie hat switch to control the pitch trim?

Perhaps if you can include a picture of your stick, it will help
 
What Mike W said, switching the trim needs a double pole double throw momentary switch wired in a particular way. Simple single pole switches won't work. The coolie hat must be used to switch a relay that switches power to the trim motor. Alternatively just put a DPDT switch on the panel.

Pete
 
From the schematic, the pitch trim motor are controlled by pins 6 & 9. What happened when you apply 12V power to either pin 6 & 9? Provided this is properly ground. Your video shows you are applying power from the Arduino board to the pin but the schematic shows this is for the AP servo instead of the pitch trim servo motor.

Next, are the push-button trim switches correctly wired to the Pin 6 & 9?
 
Do NOT connect 12 volts. The pitch trim controller is a 5 volt system.
The Ray Allen G405 stick grip grounds the RED (Down) and GREEN (Up)
wires when the switches are pressed. Measure the voltage on POWER
MODULE 50 pin D-Sub connector pins 30, 31, 42, 43. The voltage should
drop from 5 volts to zero volts when the corresponding switch is pressed.
 
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