ESC shutting off

[Rooles]

I am having issues with my granite bls. My esc shuts off everytime i try to run my truck. The lights on the esc shut off and the throttle becomes unresposive. A couple of seconds i get the same sound i get when i turn on the truck. This keeps happening. Wierd thing is that the steering remains on. Anyone know what could be going on? Thank you

 

[Pac man]

Good question I have the same issue
Any help would be appreciated thanks

 

[Rooles]

here is a video. it doesn't show but the steering servo is the only thing that responds whenever it shuts off like this

 

[springboardz]

I believe that you are having the same issue that I had with my Arrma Talion BLX. I spoke with customer support and they had me send in the motor and ESC for an assessment and potential warranty replacement (for the ESC, probably not the motor). I just sent it last week, so I don't have any further updates yet.

Details of my issue are listed below - if it lines up with your problem, then call support (they're very helpful, but busy this time of year). They'll probably ask you to send in the ESC (and probably motor too) for testing.
________________

At first, the motor would click once, then the ESC's blue light would flash and there would be two beeps. After the beeps, the motor would work again for a short, rather inconsistent time (1-30 seconds) before occurring again. The steering servo would never stop working.

However, after a few more runs the situation got worse: I would connect a LiPo battery, turn on the transmitter, then turn on the ESC (just like the manual instructs you to do): the blue LED would flash 4 times, pause, then repeat the flashing cycle. There were no longer any beeps and the motor would never engage. The steering servo would still work the entire time.

The manual only notes that a flashing blue led means low voltage, which was definitely not the case.
________________

 

[travis328]

I had the same issue on my Senton. I diagnosed the ESC being the culprit so I contacted Arrma and they replaced my ESC at no cost.

 

[Rooles]

I called Arrma and the rep said it had something to do with cogging. The rep sent me a new motor. I still think it may be the esc

 

[springboardz]

I had never heard of cogging before; thank you, Google, for answering that question. For those curious like me, here's a YouTube video I found that explains it in quite a bit of detail for RC's. Not that I am doubting the Arrma rep, but I'm rather unconvinced as well that motor replacement is the solution for this situation.

 

[Rooles]

Yea we will see . The way he explained it the cogging is causing the esc to overheat. But i can easily touch the esc as soon as it happens and at most it feels warm. It happens within 1 min of running.

 

[springboardz]

I guess you're right - we'll see. I certainly hope that the rep is right so that you can get back to having more fun with the truck!

 

[Rooles]

I just read this post. Im going to check my connections when i get home tonight.
http://arrmaforum.com/threads/esc-losing-power-randomly.482/#post-4760

 

[Rooles]

Well it was worth a try. But the dean connections are good. Will have to wait on the motor now and see

 

[springboardz]

After hearing what a number of members of this forum have been saying, I'm planning to either put on real Deans connectors or just switch to EC5 (because that's what I have on all my LiPo's)

 

[Rooles]

UPDATE: I did some testing to see if i could get more info on my issue. The first thing i did was remove the tires and ran the truck. The truck ran for about 5 seconds full throttle then the motor started to slowly get slower and slower until the esc shut off and restarted. So the issue has nothing to do with overload on the motor. Second thing i did was perform the previous test while checking the voltage of the battery. The battery voltage dropped from 7.9 to 4 volts within 3 seconds. Does this mean the issue is the battery?

 

[springboardz]

Good testing idea. I would certainly try a second battery (assuming that you have one) and see if you get the same results. Assuming that it's a LiPoly battery, are you using a battery voltage meter connected to the JST connector (Like an EOS Sentry or LVM) to monitor the voltage while it's connected? (Just curious) If you're experiencing that kind of amp draw from the battery, it could certainly be a bad battery or a bad ESC that is overdrawing current... but it could be many other things too. But probably not a loose connection.

 

[Rooles]

Its the original 3300mah nimh battery. I tested the voltage by not fully plugging in the deans connector and stuck the leads from my multimeter in between them. I ordered a lipo battery and will test to see if that changes things.

 

[springboardz]

I'll let someone smarter than me answer this question: Is it normal for an NiMH pack to drop in voltage like that when full power is being applied to the wheels in free spin?

 

[itsachevy]

It sounds like the battery cables are bad so a new esc is in order. The cable proably has a brake in it

 

[Rooles]

Okay so i did some further research into the forum that lead me to believe it was a bad battery. In the forum it suggested to charge the nimh battery at a very low amprage. I charged the battery all night at 0.1 amps. When i woke up i finished charging at 1amp. That did the trick! The truck is running like a champ!!

 

[springboardz]

Wow - wouldn't have expected that as the solution. Nice troubleshooting!

 

[Rooles]

Thanks!!! I wanted to make sure i did everything i could in my part to fix the issue.