Cars Servo problems

marccc

New Member
My truck's steering servo and gear change servo is making a buzzing noise and it doesnt work when i change gears or try to steer, is there a solution to this problem? or are both my servos dead cause i found it weird that both servos simultaneously are not working.
Appreciate the help!
 

D.O.G.

Goblin 380 Supporter
Welcome to the forum Marccc. Have you tried switching out the servos with other servos, if you have spare ones laying around. Yes it's weird that both servos simultaneously have gone bad but it can happen. Have you also check to see if every linkage or parts are moving freely without power to them. Buzzing noise could mean that there is some resistance on the servo making it not work properly. Just my 2 cents. Someone else will chime in and give you better advice then I can.
 

marccc

New Member
Welcome to the forum Marccc. Have you tried switching out the servos with other servos, if you have spare ones laying around. Yes it's weird that both servos simultaneously have gone bad but it can happen. Have you also check to see if every linkage or parts are moving freely without power to them. Buzzing noise could mean that there is some resistance on the servo making it not work properly. Just my 2 cents. Someone else will chime in and give you better advice then I can.
Hello D.O.G, thanks for your reply! No as i am currently not in my hometown, i am limited with tools and supplies, i dont have another servo. I am sure there is nothing resisting the servo, as i disassembled both servos from my truck and the buzzing noise is still here.
Before both my servos go bad, i accidentally forcefully steered the steering servo with my hand while it is turned on, which might explain why it doesnt work, but i dont know why my speed change gear servo doesnt work as i didnt touch it. My receiver shouldnt be the problem too because when i put the motor plug in the steering channel, it works fine.
Really appreciate your reply D.O.G., i am new to this forum and wasnt expecting a reply, so thanks a lot!
 

D.O.G.

Goblin 380 Supporter
Really appreciate your reply D.O.G., i am new to this forum and wasnt expecting a reply, so thanks a lot!
Your most welcome. I'm sorry that I wasn't any help to you. You not being home will give time for others to chime in. On this site, we try to help each other out so everyone can enjoy this hobby without being judged by the questions they ask :).
 

RandyDSok

Well-Known Member
marccc,

If you have the same problem with the servo's outside of the vehicle as when they are installed... it does sound like they are bad despite us not being able to say why the other servo ( for your shifter ) went bad or not. The next step would be to test with a known good parts and the servo's are the most likely to have failed... the gears inside the servo's are the most likely parts that will fail on one. In short, you test by a process of elimination at the point you are at now.

Try looking for a hobby shop or perhaps an RC club where you are at... often they will help with matters like this before you have to buy a replacement just for a test. If you can find either of these.. take one ( or both ) of the servo's with you... If they are really helpful, bring the car/truck along just in case. I'll list a few other ways to test but in each you need additional stuff...

A known good servo... the one suggestion already made tests if the receiver works fine also. If the problem goes away you know it's the servo, if the problem remains, then the receiver is likely bad.

Use a servo tester... This works similar to the last test... if the problem servo now works, the receiver is in question... if it still buzzes... then the servo is bad. The downside to this, while a servo tester is really handy to have... you end up spending money and still having the problem if the servo is actually bad. I'd suggest getting a known good servo first and then later when you have time, pick up a servo tester sometime in the future.

Use a known good receiver... Not as recommended as just getting a known good servo since that is the main suspect part... but it would help a little in testing anyway. Again, if the receiver doesn't turn out to be the problem, you'd still need a servo to finish out testing. So again, I'd get a servo first before trying other parts.
 

marccc

New Member
hello randydsok, thanks a lot for your reply, i will do everything you listed, hopefully i will pinpoint the problem asap, cause i only finish building this rc a few weeks ago, is it normal for a rc servo to have such short life span? everything is new and i played it 4- 5 times without any crashes or physical damage. Regardless, really thank you for your detailed and full coverage reply!
 

RandyDSok

Well-Known Member
I included several ways to get to the same conclusion so you had options on which way to check... You should only have to do one at most two of those...

Is it normal... that depends on the quality of the vehicle... A toy grade will often fail pretty quick while higher quality hobby grade ones will often last years ( or until you do crash etc ). You'd mentioned moving the servo while powered on... that is certainly not good for it either and could have been the cause on that one servo. So I have no idea of what model you have ( and really don't need to know in this case ), it's quality etc or what exactly has happened... All that matters at this point is that it isn't working properly and the next step is to find out why and repair it if it isn't too costly to do that.
 

marccc

New Member
I included several ways to get to the same conclusion so you had options on which way to check... You should only have to do one at most two of those...

Is it normal... that depends on the quality of the vehicle... A toy grade will often fail pretty quick while higher quality hobby grade ones will often last years ( or until you do crash etc ). You'd mentioned moving the servo while powered on... that is certainly not good for it either and could have been the cause on that one servo. So I have no idea of what model you have ( and really don't need to know in this case ), it's quality etc or what exactly has happened... All that matters at this point is that it isn't working properly and the next step is to find out why and repair it if it isn't too costly to do that.
yes, going to get my new servo and receiver tomorrow. If i were to disassemble both broken servos, what can i look for to check for damage and how should i fix it? i could take a picture and post it here for you to see if that helps!
 

RandyDSok

Well-Known Member
The only "broken" things you can see would be the internal gears... beyond that are electronics and to test those requires experience, not explanations.
 

marccc

New Member
The only "broken" things you can see would be the internal gears... beyond that are electronics and to test those requires experience, not explanations.
Hello randydsok, me again, just a quick update about my situation!
I got some new servos and tested it on my receiver, but the problem is still here, the new servos dont work and the buzzing noise can be heard from the new servos! So now it is clear that the receiver is the root of the problem.
However, when i put my my throttle control into channel 1, i can control the motor with the steering on my transmitter. So the conclusion is, the channel 1 of my receiver doesnt read the actual servo plug but reads the motor plug which i find really weird.
But based on your experience, is my situation common or one of a kind?
thanks in advance!
 

RandyDSok

Well-Known Member
What channel is mapped to a set of pins will be unique to each system... All I can do is refer you to your manual for that info since there is no set standard.

For example... On my Futaba... ch1 is aileron and ch3 is throttle ... so what my setup is doesn't mean you will have the same... so read your manual to see what yours should be. If you lost your manual.... hook things up outside of the vehicle and just plug in one servo then you can map it manually.. ie plug in at the 1st set of pins, and move every control on your radio and write that one down, then repeat it for each additional set of pins. Usually these are written on the receiver but it differs ( like a small receiver may not have room for labels as one possible reason ).
 

marccc

New Member
What channel is mapped to a set of pins will be unique to each system... All I can do is refer you to your manual for that info since there is no set standard.

For example... On my Futaba... ch1 is aileron and ch3 is throttle ... so what my setup is doesn't mean you will have the same... so read your manual to see what yours should be. If you lost your manual.... hook things up outside of the vehicle and just plug in one servo then you can map it manually.. ie plug in at the 1st set of pins, and move every control on your radio and write that one down, then repeat it for each additional set of pins. Usually these are written on the receiver but it differs ( like a small receiver may not have room for labels as one possible reason ).
alright, thanks randydsok
 
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