Servo problems (confused)

[Nordklint]

Hi, first time post! Fairly new to RC, bought an AMP Crush for my 4year old in April and an AMP MT kit for myself a couple of months later. Had a lot of fun with it and driving was pretty reckless so no surprise when my AMP MT after a flip completely lost steering. After some detective work and cross testing between my MT and Crush I figured out that the servo was dead. So I ordered a new one, a Power HD LW-20 MG! But when I plugged it in to my MT it only responded to my first 2 turns an then it stops and only a quiet ticking sound can be heard from the servo. I then plugged in my new servo to the Crush and it turns fine. So maybe there is something wrong with the ESC on my MT I thought and plugged the servo from the Crush in to it and to my surprise the gears are turning. How can this be? The ESC in the MT and Crush looks to be the same so why is the new servo not “compatible” with my MT? Any ideas? Please help.

 

[WithinU]

Just a stab in the dark, but in your partaking of the RC air ballet, you could have damaged your ESC/RX component as well.
Did you happen to test the old servo on the other car to see if it worked on that one too like the new servo?
IF the ESC/RX is the same in both cars, try swapping that out from car to car, and see if the malfunctioning servo follows. If it does follow, than I would highly question the ESC/RX component.

 

[Nordklint]

Just a stab in the dark, but in your partaking of the RC air ballet, you could have damaged your ESC/RX component as well.
Did you happen to test the old servo on the other car to see if it worked on that one too like the new servo?
IF the ESC/RX is the same in both cars, try swapping that out from car to car, and see if the malfunctioning servo follows. If it does follow, than I would highly question the ESC/RX component.

Yes I tried the old servo on the Crush as well and it‘s completely dead.
I also connected the ESC/RX from the MT to the Crush servo (not by swapping them but by parking the cars next to each other and swapping the cables over) and was able to turn the wheels on the Crush so there is nothing obviously wrong with it. Really odd.

 

[Thunderdonkey]

Yes I tried the old servo on the Crush as well and it‘s completely dead.
I also connected the ESC/RX from the MT to the Crush servo (not by swapping them but by parking the cars next to each other and swapping the cables over) and was able to turn the wheels on the Crush so there is nothing obviously wrong with it. Really odd.

Could it be a mechanical problem in the servo? If the gears are damaged it may be able to turn the wheels when there is no load, but not when there is a lot of friction.

 

[Nordklint]

Could it be a mechanical problem in the servo? If the gears are damaged it may be able to turn the wheels when there is no load, but not when there is a lot of friction.

Could it be a mechanical problem in the servo? If the gears are damaged it may be able to turn the wheels when there is no load, but not when there is a lot of friction.

Hmm no I don’t think so, it’s brand new and the servo works fine when tested through the Crush.
Did another test right now and it’s like the MT is to weak to move the gears. It responds from the first couple of turns on the radio then nothing. (All batteries are charged). Could it have something to do with voltage on the servo? Does it have to match the battery voltage? It says 4.8-6.6v on the servo spec, battery is 7.2v.

 

[Thunderdonkey]

The ESC normally regulates the battery voltage down to 5V or 6V for the servos. The standard servo in the AMP MT is rated 4.8 to 6V so your new servo should be OK. You may have a bad electrical connection. Hold the steering hard over to one side. Waggle the servo plug in the receiver and see what happens. If the servo jerks about, its a connection problem.

 

[Nordklint]

The ESC normally regulates the battery voltage down to 5V or 6V for the servos. The standard servo in the AMP MT is rated 4.8 to 6V so your new servo should be OK. You may have a bad electrical connection. Hold the steering hard over to one side. Waggle the servo plug in the receiver and see what happens. If the servo jerks about, its a connection problem.

Thanks, tried what you suggested but didn’t really get anything out of it. Anyhow, order a new stock ECS/RX, let’s hope that’s working!

 

[TheRuckus]

Is the MT not an all in one ESC and Receiver? Does anyone know the output voltage for the steering on the all-in-one receiver? If the servo works fine plugged into another standalone receiver and esc then maybe the rtr all in one can't handle the power the new servo is trying to pull.

 

[671crwlr]

Just a stab in the dark, but in your partaking of the RC air ballet, you could have damaged your ESC/RX component as well.
Did you happen to test the old servo on the other car to see if it worked on that one too like the new servo?
IF the ESC/RX is the same in both cars, try swapping that out from car to car, and see if the malfunctioning servo follows. If it does follow, than I would highly question the ESC/RX component.

I may know the issue as I Literally just had the same exact problem almost to the T as you. (Ticking, no response, & all).

I myself am fairly new to the hobby, & just realized I did the newbie mistake of not calculating the total output of the new totally overkill of a servo I accidentally bought (25KG) for a replacement for a teensy, normal, MICRO SERVO!

I was impatient & frustrated at the time & learned a valuable lesson thinking it was my brand new huge, bigger than my rc servo that was the issue as I bought it fairly cheap online. I was disappointed it gave out after a few hours. I ordered the correct part afterwards & when I connected it to my receiver, it too was not working! Now I'm really frustrated thinking I may have bought an expensive replacement for a cheaper totally wrong part. I did as you did with troubleshooting, wire switching & everything was just fine with the receiver input but neither servo worked. I was beyond baffled, I even had to take a minute to recollect what was happening. I thought I was for sure screwed having to buy a whole new receiver & remote perhaps. Looking at prices online, & how much I had spent on it so far, I reconsidered trying one last time to figure this out.

Again, I did as you tried, (all this prior to me stumbling across this thread)***

I swapped out my ESC since I did have a sparebrand new one in case, & soon as I plugged it in, BAM! IT CAME ALIVE!

Right at that moment it slammed me like a ton of bricks, IT WAS WAY TOO POWER HUNGRY FOR MY STOCK ESC AS I LITERALLY JUST READ ABOUT A FEW DAYS AGO ONLINE! the servo required a MINIMUM of 6.5v all day to function properly. My poor 60a ESC was SUFFERING trying to keep up the power demand of that beast!

I went back online to look at its specs, wow....I basically tried to fit an elephant in a size 10 shoe & only managed to barely keep one toe inside! It was a High Voltage servo!

Glad I didn't kill my receiver first! Also during troubleshooting, I've learned a few new things! The possibility of using the turning knob of the control to use as fwd & rev function when switching wires (sounds no brainer but it's not supposed to recognize such functions!) && also using ch.(x) also as a function of movement when plugged in & switched over accordingly. Only thing is you only get 1 speed....MAX

So yea hope this helps bro. sorry had to share my struggle incase someone comes across it also.

 

[Nordklint]

I finally got my new ESC/RX and installed it and the servo now works! Now the problem is that the wheels turns to slow, it’s a very noticeable difference between it and the original Crush. The new servo is a 20kg so maybe it’s like 671crwlr says, it’s a power issue? Or maybe it’s just badly installed, need to take another look at it.