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Steering servo locks to right when turned on, help!

cabech984

Newbie
Joined
Apr 9, 2020
Messages
3
Location
Dayton
Hi all, I have a wraith that has been sitting for a couple years now. I decided to clean it up, and swap the stripped transmission gears that downed it years back.

I noticed that when I turn it on, the wheels lock to the right and the steering servo motor is loading up and keeping it in place. The throttle doesn’t work during this either. If I unplug the servo, the throttle works fine in both directions as well as the drag brake. If I plug the servo into the port the throttle is connected to, I can get the wheels to turn left and right with the throttle trigger. I threw a new factory TR325 receiver and a new battery in it and the same thing happens.

I’m kind of leaning towards the EX-2 esc to be faulty at this point. It’s kind of my last option, what do you think?

I also swapped a new Savox SA1230sg into it after the fact for upgrades. Will I need anything different to help power this? Like a BEC?

Thanks!
 
I would disconnect the servo horn then set the steering trim to center and rebind the receiver. You may want to recalibrate the ESC after re binding as well. Check to see if you can turn left and right before you hook the servo horn up. Once you verify the servo can turn left and right, hook up the servo horn with the radio powered on so you can maintain center. If your radio has a sub trim adjustment you can set that first before setting the final trim. If your radio has adjustable end points, set those so the steering doesn't try to go past the physical limits left and right. If you don't have adjustable EPA then you can use steering duel rate kind of the same way. You might not get equal steering angle on both sides but it will prevent your servo from killing itself prematurely.

As for the BEC. check the specs of the ESC. If the internal BEC puts out enough power to run the servo then there is no point in running an external BEC.

Hope this helps.

Sent from my SM-G965U using Tapatalk
 
Okay, I'll actually start at the end. You will need an external BEC with the Savox servo, stall current draw is 4+ amps. The AE2 ESC only puts out 5V, 2 amps. Also, the ESC is probably okay as all it does is provide power from the battery to the motor, power for the receiver through the built in BEC, and the throttle forward/reverse signal. The steering port gets power for the servo through the receiver.

Your original info about the throttle and steering servo is classic for electronic servo failure. The fact you get full throttle control with the servo disconnected and then the servo works when plugged in to the throttle port indicates the servo should be okay and the receiver is suspect. One other thing to try is to plug the throttle wire in to the servo port and see if the motor will forward/reverse using the steering wheel. I'm now confused that you still have the problem after replacing the servo and the receiver.

The only other thing that comes to mind is, the transmitter itself is the problem. Something haywire with the steering control in the transmitter.

Do you have a different transmitter/receiver you can try? Seems like the transmitter is the only thing left from the original issues you had.
 
I noticed that when I turn it on, the wheels lock to the right and the steering servo motor is loading up and keeping it in place. The throttle doesn’t work during this either. If I unplug the servo, the throttle works fine in both directions as well as the drag brake. If I plug the servo into the port the throttle is connected to, I can get the wheels to turn left and right with the throttle trigger. I threw a new factory TR325 receiver and a new battery in it and the same thing happens.
Thanks!
Obviously there is something wrong with you TX/RX if servo goes mad in 1st channel and works fine in 2nd. To make sure plug your ESC in 1st channel and see what happens. If motor starts spinning after you turn it on, this is it.
Probably potentiometer in your steering wheel is drifting and provides different signal now or even dead. Some TX (like Radiolink that I use) allow reset and recalibration of potentiometers. Google it for your TX.
I also swapped a new Savox SA1230sg into it after the fact for upgrades.
Does the same thing happens with new servo?
 
Last edited:
Thanks for the replies guys!

I actually checked a few of these things before posting.. the issue happens with either servo I used and also with the steering horn removed. It also did spin the tires when I swapped channels. I’m going to borrow a buddies receiver and see if that fixes it because that definitely sounds suspect!

I’ll look into the BEC for the new servo. Does anyone have a recommended upgrade?
 
A buddy brought a transmitter over for me to test with. Turns out, my transmitter is the culprit. Thanks for the assistance!
 
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