Car cuts out after a shock from a jump tekin rs pro??

[cs8sz]

Hi,

Please help!

I am an experienced racer, but I can't find this problem with my car and it is well annoying!

Basically after a jump and only after a jump the motor cuts out for a few seconds until the speedo starts up again and you are off!

I am running the Futaba Fasst system 603fs reciever and a Tekin RS Pro speedo, and savox servo. I have tried replacing the reciever, Speedo, motor batteries and it still happens! The replacement ones were from my touring car, and were the same models.

The unfortunaltey it is impossible to replicate in the pits no matter how manys times you drop it on the floor! Also due to the fact that the Futaba system boots really fast it also isn't possible to tell if the whole car goes dead or not, however I would say that the servo does appear to work all the time and the speedo does seem to take quite a long time 5 seconds or something to come back alive.

I have also tried replacing all the plugs.

Any help would be very appreicated!

Chris

[Jamie.T]

Me and a friend of mine both had the same problems with our Rs pro's. I spoke in depth with Steve (DCM) and he raised the issue with Randy at Tekin.

The first question he asked was if the motor screws were slightly too long, and on a hard landing they could possibly be disturbing the motor and sending the ESC into shut-down mode.

The other observation that was made is that it only seems to be happening in shaft driven 4wd cars where the motor sits lengthways (i.e, same direction as shaft).

I removed the entire system from my 502 and installed it on my belt driven 511 where the motor sits side on, an since then ive not had one single issue, and neither has my friend as he also changed cars.

What car is yours running?

[cs8sz]

Hi,

Thank you so much! It is Chris here again with the 502x I posted a bulk head issue a few weeks ago.

So in answer to your question it is a 502x!

Out of intrest I did lend the motor Tekin 5.5 to a club driver in a Kyosho shaft and the motor was fine with a LRP speedo. Do you know you I can get this resloved by in Tekin as it is really annoying.

Thanks for your help!

Chris

[Jamie.T]

The problem lies with the ESC itself, but is essentially caused by the motor it seems, but as soon as the motor is rotated the problem goes away.

Its bit of a strange one to be honest, and to date Tekin has no idea what can be causing it. The only things they suggested was the motor screw length and to ensure you have a power cap in the receiver, especially if its a micro spektrum receiver.

If i had continued having these issues after installing in my 511, my solution was to change the brand of ESC. Sorry i cant be of any more help than that, but not even Tekin themselves are able to identify the problem, let alone overcome it.

[Big G]

Strange you should mention that.

I'm running a RS pro with Futaba's FAAST system in my Durango and at Oswestry on Sunday in the final about 4 mins in the car would just stop dead in the middle of corners. Mine didn't seem to be related to jumping...

I ran a 6.5 Novak Ballistic motor that day. I swapped motors to a SP V3 5.5 now and ran the car down the local club without any cut outs...

When I turn my car on initially it takes a couple of seconds to let me throttle. the steering works instantly. Is this normal?

In the races it was only cutting for half a second and it was hard to work out if it was happening when I was off power as it was usually just as I was on throttle trying to get out of the corners. I tried to drive without letting off the throttle completely, but couldn't avoid the cutouts

[HarlowS]

The few seconds delay on boot up is normal, its checking for transmitter signals.

I dont think that the issue you had on Sunday was speedo related, it was all too quick, looked more like a sensor issue as it was only mid corner when the car was nearly at a stop. May be worth swapping sensor lead and motor to see if its any better.

<<<<Just read again that you changed the motor so looks like that was indeed the problem, did you use the same sensor lead or a different one ??? >>>>

Strange you should mention that.

I'm running a RS pro with Futaba's FAAST system in my Durango and at Oswestry on Sunday in the final about 4 mins in the car would just stop dead in the middle of corners. Mine didn't seem to be related to jumping...

I ran a 6.5 Novak Ballistic motor that day. I swapped motors to a SP V3 5.5 now and ran the car down the local club without any cut outs...

When I turn my car on initially it takes a couple of seconds to let me throttle. the steering works instantly. Is this normal?

In the races it was only cutting for half a second and it was hard to work out if it was happening when I was off power as it was usually just as I was on throttle trying to get out of the corners. I tried to drive without letting off the throttle completely, but couldn't avoid the cutouts

[cs8sz]

Hi,

sorry I didn't answer your question the motor screws are short if anything there is no way they are too long. I am running a power cap on the speedo infact I replaced it last night as it was broken but made no difference.

Thank you very much you have been very helpful at least I know it is the speedo, I think I will try and go down the route of asking for a refund!

Chris

[Big G]

Same sensor lead Stu. Amazingly I have the boxes for 4 SP V3's on my window sil, yet can only find 1 sensor lead lol. The other 3 must have done a runner!

[HarlowS]

Where did you get it from and how long ago ?


Hi,

sorry I didn't answer your question the motor screws are short if anything there is no way they are too long. I am running a power cap on the speedo infact I replaced it last night as it was broken but made no difference.

Thank you very much you have been very helpful at least I know it is the speedo, I think I will try and go down the route of asking for a refund!

Chris

[cs8sz]

Hi,

I have 2 RS Pros one in my touring and one in my buggy I swapped them over to see if there was any difference but there wasn't. I bought them around november last year (the oldest one) with a newer one about January ish this year. I bought them from insideLine racing www.the-pred.co.uk Kevin Lee in the UK. In the touring car they are brilliant! I am only looking to get a refund or whatever on one of them.

Any ideas what I should do??

Chris

[HarlowS]

Not quite sure if a refund is on the cards but repair/replacement would normally be the route to go. Contact Kev Lee in the first instance.

Very strange fault though, i run the durango and cant say i have experienced it with the 2 Tekins i have.

[HarlowS]

Just realised that you may be out of luck as the Warranty period is 120 days.

[Randy p]

Guys there is a lot of speculation here and none of it official from Tekin. DCM and Harlow are correct in the sense that it doesn't sound like the esc.

Shutdowns can be hard to diagnose but here are a few things to look for:

1. Do you have steering?
2. Did you loose steering when the shut down occured?
3. How many minutes into the run?
4. Did the car loose speeed prior to the shutdown?

A few things to understand. The BEC circuit powers the motor sensors as well as ANYTHING else plugged into it: Servo, receiver, personal transponder, fan if equipped,etc.

Some of today's servos can yank more power than ever. How else to they attain these crazy speeds and torque right? This can overwhelm the "standard" 3 amp bec at times. Some of the receivers out right now also cannot handle this load as the filtering system in them also get's "browned out" and will cause a reset.

During such a reset we will "wait" until we see a solid neutral signal. Until this occurs we will do nothing.

95% of today's 4wd cars are shaft driven. I run a Durango Dex410 and have been for well over a year now. No issues.

So please post what radio/servo/motor you're using and I will look to help you diagnose your issue.

[Jamie.T]

Trouble is tho, i took all my electrics out of my shaft driven car, installed them all in my belt driven car and hey presto, it works...

This has to suggest something and will certainly be an angle to target the fault from.

[HarlowS]

It certainly would be good to see if there are any similarities in servo and receiver combos with cars that have had this issue.

I recently saw a Savox servo cause a speedo to shut down after about 4 mins, too kages to find out it was the servo. Swapped that out and all is ok again now.

[HarlowS]

But that would also say that the speedo and other gear were'nt technically faulty wouldnt it ??

Intermitent elctrical faults are always the worst to solve :confused:

Trouble is tho, i took all my electrics out of my shaft driven car, installed them all in my belt driven car and hey presto, it works...

This has to suggest something and will certainly be an angle to target the fault from.

[Randy p]

Trouble is tho, i took all my electrics out of my shaft driven car, installed them all in my belt driven car and hey presto, it works...

This has to suggest something and will certainly be an angle to target the fault from.

There's simply too much to assume was left unchanged. I'm telling you that there is NO issue with a shaft driven layout that would cause the esc to operate incorrectly.

The motor/drive train layout will cause no ill effects period.

[Jamie.T]

To make my case stronger, my friend has also been having trouble with his Rs pro in a dex410, he then transferred ALL of his gear into a 511 belt drive car, and hes never had a problem since.

I also know that Steve (DCM) has also come across similar problems in the past with other Tekin owners and despite trying different motors, servos and receiver, the problem persists. Weird................

[Randy p]

Right, and I'm here to tell you that it has NOTHING to do with it. I can't stress this enough.
What does that say for the thousands of others succesfully using the RS Pro in shafty cars?

Again, I'm here to help. Please post up the hardware you're using so I can sort everyone out.

DCM is a great team driver, but I'm pretty sure I'm a bit more versed in the product ;)

[cs8sz]

Hi,

Thank you very much for replying, right in answer to your question:

Tekin 5.5 motor
Futaba Faast 603fs reciever
Tamiya 502x
Vampire 5400mah batteries (have tried to change this)
Savox low profile servo 1251 I think

I am running the latest software on the tekin.

I tried receiver cap but didn't help, and am running the standard cap on speedo.


Thanks Chris

[Randy p]

OK, do you have access to another servo? When you installed the receiver cap which port did you put it into? What cap was it?

[cs8sz]

Hi,

Me again in answer to the post higher up the thread from Randy, I have steering at all times, In Terms of how long into the run seems random I have it happen after just 30 seconds and sometimes at the end, middle etc, I have checked and it isn't thermalling. Speed was fine before the shut down and after when it found the neurtal postion the only solution I found was to not get any air at all.

It is really bugging me that is for sure.

Thanks for your help.

Chris

[cs8sz]

Gosh you are fast.

Unfortunatley not, I have access to another Savox servo if that is what you mean from my touring car, but the shut down ocurrs without the use of any steering??

Not sure which port I plugged the capacitor into to be honest, it was one that I had left from the Spektrum days.

Thanks Chris

[cs8sz]

Sorry I also forgot to say that I did try a run without fans in it, and it still cut out after after the second jump test. It is also impossible to test in the pits which is even worse.

Thanks Again

Chris

[Jamie.T]

My set-up was:

TRF502
Rs pro with latest software (Vega 2.something)
Savox 1251 and tried futaba
Intellect Ib4200, also tried speedpower 4200
Spektrum sr3001 receiver, also tried Sr3500
Powercap is a 300Uf 16v, also tried genuine spektrum one.

But, i did try another ESC, and guess what, NO problem. What does that suggest??

Im sorry Randy, but i find it very difficult to understand how your writing off the fact that the Tekin is at fault, i understand your clearly biased but when 2 different people transferred their gear into non-shaft driven cars and suddenly all problems go away, surely that would suggest something. And the fact that when i used another brand of ESC (lrp) in my 502, it also cured the problem??

[Randy p]

I am not saying that the esc can't be the issue. What I am saying is that the fact that the car is a shaft driven one has NOTHING to do with this concern. The esc could care less what drivetrain is in the car.

To the esc a load is a load, period. What esc did you try?

If you only have access to a Savox servo you can bypass the bec circuit to eliminate the servo as the issue. This is done by taking a line from B+ and wiring straight to the servo's red wire on the servo lead. This red wire must be removed from the servo's connector.

[Jamie.T]

I am not saying that the esc can't be the issue. What I am saying is that the fact that the car is a shaft driven one has NOTHING to do with this concern. The esc could care less what drivetrain is in the car.


Im sorry Randy, but i have to disagree, the fact that the issue was resolved on 2 separate cars of a different brand by just switching to belt drive is more than just a coincidence .

Also, im not really too bothered anymore as i no longer have the problem and i love my Rs pro, but nevertheless an issue is clearly there and needs addressing.

[Randy p]

I'm sure that explanation works for you. However it doesn't for me. The RS Pro works just fine in the B44, ZX5, Durango, Tamiya and many other shaft driven 4wd cars... so why only these two cases?

I'm listening but don't see that two cars create and "issue."

[Jamie.T]

Its not 2 issues and you know that, DCM has told me that these issues have been raised in the past and hes discussed them with you to try and resolve to no avail !!

As i said, i dont wish to continue discussing it as the issue has now been resolved for me, but i only raised the point as the creater of this topic is suffering from similar issues.

[DCM]

I would be happy for it to be a coincidence as to chassis format, have you had any issue like this your side of the pond, Randy? Just the only time I have heard of it has only been in shaft drive, and belt is still pretty popular in the UK.

[Randy p]

First I've even heard of a "Shafty" issue to be honest. Hell I chuckled out loud at the notion when I saw this on the Tekin forum at first...

Something is being missed here.

[cs8sz]

Hi randy,

Right thank you for your help I will try swapping the servo and hotwire it, can they take the extra voltage?

I am also going to test my car around my street with a nice ramp!

Thanks Chris

[Randy p]

I know most of the Savox servos are rated for 7.2 v use but double check yours.

[dodgydiy]

one point worth noting, belts will absorb some impact and may slightly cushion the kick delivered through the drive train back to the motor on landing from a jump. this could produce slightly less of a sudden spike in voltage and current. it might be worth if possible turning off the failsafe settings for your receiver to see if the failsafe is being upset by this, also could the speedo be upset by this and drop into failsafe. if this was happening then it wouldnt do it for everyone as all driving styles are different, some people are far more gentle on the throttle than other etc...

[Randy p]

That statement is vaild in regards to driving style,etc.

The RS however has no "failsafe" in regard to current draw other than voltage cut off. This of course is entirely possible under huge current draws. This is why I'm asking about runtime,etc.

A quick test would to simply turn off the low votlage protection and run the car. If the problem is gone, you've found the issue.

[InsideLineModels]

I've run this speedo for over 3 years in 2 different shaft drive cars (Aero and now Pred) and have never had this issue. I've also used Orion, savox and now Spektrum servos.

Next wednesday we'll have another look Chris, and i'll try and be ready to have a quick look at what error lights are displying on the speedo during shutdown and then report back to Rp.

I'm sure we'll sort this out.

Kev

[cs8sz]

Hi Chris here again!

I have the holly grail I have the error codes! After jumping my car out the front for ages I got the codes so here it is:

After the intial impact the DB light flashes for a few seconds (no clue what that is) After that 3 light flash up, one in the middle and 2 either side on the outside after then an audible beep, then the speed is reset and find the neutral etc and you are off.

Also it requires a light jump not a massive impact where I broke my speedo fan!

Any help to know what these are would be great, as the manual is no help!

Chris

[DCM]

Looks like the normal arming sequence that, mate.

[msxmre]

Well not wanting to look like i'm siding with Tekin but i run Tekin RS Pro in my Tamiya TRF502X, TRF201, my sons TRF201 and Durango DEX410 and i can honestly say that i've not had 1 instance of problems or bother with any of these speedos. I think that they're genuinely the best out there at the moment and the size of the speedo is what attracted me to it especially TRF502X and Durango, not much room. In any walk of life there's people who unfortunately don't get on with certain products, Hell i ran LRP Speedos for years and then went SXX Stockspec and absolutely hated it, hence the reason i'll never touch another LRP speedo.
I hope you get to the bottom of the problem.
Scotty......../:thumbsup:

[DCM]

Thats ok Scotty, I run Tekins in all mine and kids cars and they never miss a beat to.

[Randy p]

Ok, this sounds like the esc is going into pit tune mode. This is caused by one of the buttons being pressed. So any wires going over the top of the buttons?

[cs8sz]

Hi Randy,

Actually yes! There was the motor wire over the mode button, would this cause this issue? It does sound logical to me I hadn't though of that opps.

I hope that was the issue fingers crossed, I will report back after I have taken it racing hopefully on Wednesday.

Thanks for your help!

Chris

[Mouton]

Perhaps is was that easy, having one motor wire hitting a button. I shure hope so as that is easy to fix.

Are you sure the sensor leads (both ends) sit firmly? It may be that causing the problems. I had similar problems when the sensor wire connector at the ESC end did not sit 100 %. It looked OK but it was not.

While it is true that many modern servos draw a lot of Amps, I am yet to see one that exceeds 3 A for a standard sized servo. I have done actual measurements of current draw during use and Futaba's bigger digital servos (those aimed for 1:8 offroad) peak at about 1.5 A (when you try to steer whilst holding on to one of the front tires). The only servos I have found to exceed 3 A are digital large scale servos featuring a much bigger motors. Sanwas (Airtronics) ERG/SDX series are remarkably good in that aspect as they draw very little current compared to other makes with similar specs. Savöx have a reputation for drawing quite a lot of current, but really not more than a 3A ESC BEC should handle.

Perhaps the BEC of the Tekin is "optimistically" speced? On most receivers I have opened up, including the Futaba R603FS, all positive and negative connectors are wired in parallel (but naturally not to eachother), thus eliminating the receiver as the cutout culprit. If you want to eliminate the receiver completely, activate its fail safe settings and set it to hold the throttle input. That way it will not cause a braking effect if the receiver looses the signal and reboots.

If you only have access to a Savox servo you can bypass the bec circuit to eliminate the servo as the issue. This is done by taking a line from B+ and wiring straight to the servo's red wire on the servo lead. This red wire must be removed from the servo's connector.Only follow that advice if your servo can handle 8.4 Volts! Do that with a 6.0 Volt servo and only its gearbox and casing are usable as spares...

Considering the driving style and what dodgydiy suggests, how is the slipper set? Perhaps you could try loosen it slightly.

[cs8sz]

Hi,

Thanks for those tips, My Savox servo I believe is only rated at 6.0v volts so I won't risk hotwiring it, thanks for the reciever wiring that is very useful and for sure when the car cuts out I have steering at all times, so I hope it really is that easy!

The Savox servo 1251 has a max current at stall of 3amps but I think normally it wouldn't get close to this as you sugest. It is a shame why speedo manufacturers don't make 5amp BEC instead (The speed passion is also rated at 3amps)

Thanks for all the advice!

Chris

[Randy p]

90% of the current servos are drawing more than 10amps at a peak current spike. This is often a steering correction of the initial current to switch directions.

Put your car on the bench with weight on the tires, steer it back and forth quickly and see if you can watch your receiver reset, or led's dim out.

A DVOM or servo checker will not sample at a fast enough frame rate to catch these spikes. I'm not making this up, we've tested them all to find this issue.

Yes I would expect any new Tekin esc's being developed to have a more robust and stronger BEC in the future ;)

[cs8sz]

Hi

When is the expected release date then? I want one! May I suggest another useful feature, re-design the package to allow at small heat sink and fan to be mounted on the speedo like the other makes. As in modified it is very .difficult to mount the fan anywhere useful to cool the solder posts down.

Thanks again

Chris

[cs8sz]

Hi guys,

After racing last night I am glad to report that it seems ok, it cut out in the first round as the wires were still close to the mode button, so under instructions from kev, I took the buttons out of the case so it can't possible happen again and it worked perfectly after that, the buttons still can be used with a point.

Thank you so much for your help

Chris

[Randy p]

Glad to hear it. Funny how it can be the silliest things....

[coleman758]

Hey guys,

Ok I've been having a similar issue, my ESC keeps cutting out. Like its
resetting. Now there is no pattern to it some thimes it does it on jumps other times just in corners. I loose everything including steering.

I'm running a Savox Lopro and 5.5X12

I've tried it in my Durango & RB5 still does the same?

[Randy p]

Did you add a receiver cap to your radio system? The Savox servos cause brown outs which is what you're experiencing since you lose steering also.

[coleman758]

Did you add a receiver cap to your radio system? The Savox servos cause brown outs which is what you're experiencing since you lose steering also.

Interesting... I will have a look into it!

[coleman758]

Will say a spectrum cap work on a Futaba reciver?

[gainsy]

I got 1 of these when my savox was playing up
http://www.ebay.co.uk/itm/220733640728
Have had no problems since :)
I see no reason why it wouldn't work with futaba stuff, just make sure the plug goes in the right way up & you should be good to go

[captainlip]

Did you add a receiver cap to your radio system? The Savox servos cause brown outs which is what you're experiencing since you lose steering also.

Hit the nail on the head randy!

[Randy p]

Sweet!

[coleman758]

Nice one guys, I have ordered one of those.
Hopefully that should sort the problem!

[coleman758]

Delete Please - Sorry duplicate post