Throttle intermittently not responding

RichardT

10 mW
Joined
Mar 20, 2014
Messages
34
Hello Experts

I have been using my new ebike for about a month on a daily basis.

Yesterday, i begin to experience an issue of motor not spinning when I press the throttle while riding. I let it wait for a minute or so and the throttle effect is back again. Else, even though the power indicator is showing sufficient battery capacity, and LED lights, buzzer are working, the throttling is not functioning , as if its not pressed at all. I pressed a few times and it still does not work until i wait for a short while and then its back functioning again. This goes on intermittently.

I tried with a fully charged battery and its the same issue.

How i use the throttle is i peddal for a short while and then use the throttle to boost the speed for a while especially when nearing slopes . So, its like 50% throttling from point A to point B that is a range of about 6km per trip one-way.

So, i have been rather gently and thrifty on the use of the throttle. So, i am not sure is it the controller is overheated and disabled the throttling until its cooler again?

Could it be the throttle resistor is worn out?

Is there any known reason for this situation / problem?
 
No, it's just the usual problem, intermittent connection to the throttle. one of the wires is loose at the plug, or could have broken strands that don't show as a cut in the wire insulation.

I'd look at the wires where they connect to the plug, and the plug first. then if nothing is obvious, try a different throttle.

It's nearly always wire issues. 'but it's also possible the little magnet inside the throttle is loose. But since a throttle is cheap, I'd start by ordering a new one. A spare helps troubleshooting some times.
 
Hi Dogman Dan

Thank you very much for your kind advice. Will try it out and let you know. Cheers.
 
dogman dan said:
No, it's just the usual problem, intermittent connection to the throttle. one of the wires is loose at the plug, or could have broken strands that don't show as a cut in the wire insulation.

I'd look at the wires where they connect to the plug, and the plug first. then if nothing is obvious, try a different throttle.

It's nearly always wire issues. 'but it's also possible the little magnet inside the throttle is loose. But since a throttle is cheap, I'd start by ordering a new one. A spare helps troubleshooting some times.

Hi Bro,

I tried the 2 methods you advised and learnt some new things!

Tests done:

1. Using my spare e-scooter throttle (un-used, sitting on the shelf), there was no intermittent behavior. Works normally and even better throttle response than existing one.

2. After i reconnected to the spare throttle, no intermittent behavior. Re-inserted the connecting wires to ensure good contact.

Assessment :
1. It could be either reasons 1 or 2.
2, It could also be the throttle resistor or potentiometer is slightly faulty causing the motor to sort of loose rotation (hall sensor like not functioning) intermittently.

I wonder if i open up my thumb throttle , what can i see or repair or look out for if to diagnose if the pot is faulty?

Thanks! :D
 
Hello Experts

I have not yet decided to replace my thumb throttle and continued to use the ebike with the intermittent problem still unresolved.

I discovered that whenever the motor stops turning when i throttle, all i have to do is to come to a stop and push the bike in reverse for an inch and then the motor will work again when i press the throttle.

I wonder why turning the motor in reverse for a short distance allows the motor to spin again?

I checked the throttle voltage and it seems working fine. So the problem does not seem to be the throttle.

When i throttle harder, the motor seems to jerk or loose spinning momentarily giving a hum or sound.
At first, i thought the disc brake was jammed, but it was not. So, i not sure what is causing the sound which i suspect is the humming sound of a spinning hub motor.

Whenever the throttling does not spin the motor, i notice the power level indicator is at red , the lowest battery level indication. When the throttling works, the power level indicator on the thumb throttle shows the yellow and green lights all on as well.

Can someone give me some advice? Thank you.

Best regards
Richard T
 
Does it feel like there is a vibration coming from the motor almost as if it is a cylinder misfiring in an ICE? You could have a hall sensor out or more likely a loose hall or phase connection between your controller and motor since you were just messing with the wiring.
 
ecycler said:
Does it feel like there is a vibration coming from the motor almost as if it is a cylinder misfiring in an ICE? You could have a hall sensor out or more likely a loose hall or phase connection between your controller and motor since you were just messing with the wiring.

Yes, thats exactly what i felt!
I just did some more tests :

1. Hall wire voltage : Red and Black is about 5V. Looks ok.
2. Measured the hall sensor voltage levels , rotating wheel in reverse direction.
Blue and Black : between 0 and 5v.
Green and Black : between 0 and 5v.
Yellow and Black : when problem occurs , its essentially 0v. After i rotate in reverse by an inch , the voltage is back to 5v.

3. I then disconnected the battery pack to the controller. Then i hooked the motor hall sensor loom to a brushless motor controller tester but the tester hall signal LEDs are alternating (blinking) as if its working normally. Maybe the intermittent problem did not occur at that moment?

I really suspect the yellow wire hall sensor is bad. Its just that I am not sure how to repair this given the hall sensor is inside the brushless geared hub motor. :shock: But can a bad hall sensor still work intermittently? Why when i reverse the motor wheel direction by an inch the hall sensor works again? Is there a Capacitor issue somewhere in the controller? Or is it more like a connection issue? I checked continuity of the hall yellow wire connector and it seems ok.

Am i right to say even if 1 hall sensor is bad, the motor can still run just that its on 2 'cyclinders' instead of 3 ?

Does this mean the motor is operating at 2/3 power ? Does this reduce electricity consumption ?

I am feeling so low now because this ebike is not even 2 months old! I bought from a guy from China.
 
Because the handlebar indicator for the battery is fluctuating between actual voltage of the battery, and then low voltage...I suspect a poor connection as one of the issues. The throttle gets its 5V power (red wire) from the controller. A poor conception will not only read as a low battery, but the 5V power line might read zero intermittently.

A bad connection can be a weak soldered joint connecting the wires to the socket/plug for the throttle, and the poor connection also can be oxidation on the blades and sockets that plug into each other.
 
RichardT said:
ecycler said:
Does it feel like there is a vibration coming from the motor almost as if it is a cylinder misfiring in an ICE? You could have a hall sensor out or more likely a loose hall or phase connection between your controller and motor since you were just messing with the wiring.

Yes, thats exactly what i felt!
I just did some more tests :

1. Hall wire voltage : Red and Black is about 5V. Looks ok.
2. Measured the hall sensor voltage levels , rotating wheel in reverse direction.
Blue and Black : between 0 and 5v.
Green and Black : between 0 and 5v.
Yellow and Black : when problem occurs , its essentially 0v. After i rotate in reverse by an inch , the voltage is back to 5v.

3. I then disconnected the battery pack to the controller. Then i hooked the motor hall sensor loom to a brushless motor controller tester but the tester hall signal LEDs are alternating (blinking) as if its working normally. Maybe the intermittent problem did not occur at that moment?

I really suspect the yellow wire hall sensor is bad. Its just that I am not sure how to repair this given the hall sensor is inside the brushless geared hub motor. :shock: But can a bad hall sensor still work intermittently? Why when i reverse the motor wheel direction by an inch the hall sensor works again? Is there a Capacitor issue somewhere in the controller? Or is it more like a connection issue? I checked continuity of the hall yellow wire connector and it seems ok.

Am i right to say even if 1 hall sensor is bad, the motor can still run just that its on 2 'cyclinders' instead of 3 ?

Does this mean the motor is operating at 2/3 power ? Does this reduce electricity consumption ?

I am feeling so low now because this ebike is not even 2 months old! I bought from a guy from China.


In my experience the halls either work or they don't. An intermittent issue strongly indicates a connection issue. The only exception to this would be if the hall was in stalled incorrectly or came loose (the likelihood of this depends on how it is mounted on this particular motor.)

I recently had an almost identical situation that through me for a loop. After probing the wires to the motor and thoroughly testing the halls, I replaced what seemed to be the problematic one (was seemingly stuck high.) After installing the new sensor I found I still had the same issue and it turned out there was an issue in the stupid JST connector!!! They are cheap and can really throw you off if you trust them too much and don't double check. I wasted several hours for no reason.

The clue could be right here. When you say:

Yellow and Black : when problem occurs , its essentially 0v. After i rotate in reverse by an inch , the voltage is back to 5v.

Is it 0 or .02v? That could be a big difference in diagnosing this. You didn't describe how much you had to mes with the wiring to replace the throttle, but you should start with the most obvious and inspect all of that first since you didn't do anything that should have caused an otherwise well working hall sensor to malfunction internally or come loose. Not ruling that out, but seems unlikely unless you are leaving something out by accident.
 
spinningmagnets said:
Because the handlebar indicator for the battery is fluctuating between actual voltage of the battery, and then low voltage...I suspect a poor connection as one of the issues. The throttle gets its 5V power (red wire) from the controller. A poor conception will not only read as a low battery, but the 5V power line might read zero intermittently.

A bad connection can be a weak soldered joint connecting the wires to the socket/plug for the throttle, and the poor connection also can be oxidation on the blades and sockets that plug into each other.

I am keeping my fingers crossed that its due to poor connections. Due to oxidation ? Can brass oxidise? The wire ends seems to be soldered to brass colored pins or long flat and thin plates that go into a molex type connector. Will try using a metal brush and give the connections a good brushing .

I had pressed the connections before to ensure no loose connections . Hopefully, the root cause is poor connections.
 
Nelson37 said:
I notice the power level indicator is also part of the thumb throttle. Have you tried going back to the non-stock throttle which seemed to solve the issue originally?
Does this second throttle also have a power indicator, and, if so, have you ever had either the performance issue or the low battery indicator issue on the second throttle?

Does the low battery indicator ALWAYS accompany the problem, or just sometimes?

Both problem tags are contained in one single piece of equipment. I have no idea how this might or might not be the root cause, but this seems significant to me.

Not certain how extensively this second throttle was tested. After the remove and replace of the throttle, did the problem seem to go away for a time? Seems like second throttle solved the problem for a time, original throttle was put back on, also worked for a while (?), then problem re-appeared? Classic loose connection symptom.

Also, on the testing of yellow hall wire during problem phase - Did you check all three pairs during this time, and are you able to reliably re-create the problem phase on-demand?

Thanks very much. I will do more tests to see if the problem is repeatable.
 
ecycler said:
In my experience the halls either work or they don't. An intermittent issue strongly indicates a connection issue. The only exception to this would be if the hall was in stalled incorrectly or came loose (the likelihood of this depends on how it is mounted on this particular motor.)

I recently had an almost identical situation that through me for a loop. After probing the wires to the motor and thoroughly testing the halls, I replaced what seemed to be the problematic one (was seemingly stuck high.) After installing the new sensor I found I still had the same issue and it turned out there was an issue in the stupid JST connector!!! They are cheap and can really throw you off if you trust them too much and don't double check. I wasted several hours for no reason.

The clue could be right here. When you say:

Yellow and Black : when problem occurs , its essentially 0v. After i rotate in reverse by an inch , the voltage is back to 5v.

Is it 0 or .02v? That could be a big difference in diagnosing this. You didn't describe how much you had to mes with the wiring to replace the throttle, but you should start with the most obvious and inspect all of that first since you didn't do anything that should have caused an otherwise well working hall sensor to malfunction internally or come loose. Not ruling that out, but seems unlikely unless you are leaving something out by accident.

I like it when you say halls either work or they don't. I am really hoping its loose connections. Seems there is some chance its not due to faulty halls. If halls faulty, i would have to open up the motor casing!!! :shock: :shock: Thats why i asked what is it like if a hall sensor fails. It seems like if 1 hall sensor fails, the motor is unlikely to run. My motor still runs though intermittently. When it runs, it seems smooth like normal. The motor feels powerful like its designed to be.

The last time i measured, the yellow wire was showing all sorts of low voltages (essentially zero) including zero i believe.
I will be doing more tests and report back to the forum.
Thanks to one and all for your contributions and help! :)
 
If one hall sensor fails, the motor can still run. It will have low power and feel rough as I described earlier. This same sensation will happen with either a loose hall or phase wire as well. In addition to the situation I described earlier, I once had a bullet connector for the phase wires on one of my bikes come slightly loose. The bike would run normally, then run rough for a bit, then run normally again. I discovered one of my (factory) phase connectors was slightly melted looking. I replaced it and all has been fine for 1000+ miles.

We have not ruled out an intermittent hall sensor, but based on what you have described I would not immediately jump to cracking your motor open just yet. I would be focused on the wires right now. Unplug each of your phase and hall connectors and carefully examine the male/female pins and ports of each.
 
Over the last few years I have had multiple hall sensors in my thumb throttles develop intermittent problems before they go out. I keep a small bag of 49E Halls around just for that problem.

Also, check to see that your brake cutoff switches (if you have break cutoff switches) are not engaging and staying stuck. If your brakes are not setup properly sometimes that can happen.

Have you gotten a new throttle yet? If not, get one and see if it is the problem. Or, if you think you can open your throttle without destroying it, open it and test the hall sensor by hooking a low amp 4.5v to 5v power source to it and test it by passing a magnet closer and farther from the hall sensor faces. You will need to test both sides, not the edges.

For testing, an old nine volt battery with under 6 volts works for me.

When no magnet is near the Hall face, then it should be about 50% of what your input voltage is. A magnet to one side should produce about 1 volt. A magnet to the other side should produce very close to your input voltage.

Edit:49e Hall Sensor.JPG

:D
 
Ah, geez. I did not realize that you had gone back to the original throttle that was having issues. Just order a new one and be done with it! haha
 
Hey Guys thank you ever so much for opening up on this particular topic evidently it is a popular one at that. Identical issue here I called my old guys from the eZip Bike store as I used to own a Trike until it bit the dust, they were all saying its a battery, before contacting them I came to an uneducated guess either a throttle or controller or like one of you was saying a phase wire yellow or white, and yes i have the bullet connectors on those 3 wires only, another chap was mentioning that extended hard riding one should solder as many joints as possible to prevent accidental overheating or shorts to ground or melting wires. what my hub system did is again a Chinese model 48v 1000w brushless worked perfect for 3 months then last weekend out of nowhere I go to mash the thumb throttle to full power and as i cycle thru midway point i feel the power at about 30% and shaky to zero power at a full mash of the thumb lever. when i back off the throttle to 1/2 way down power comes back to 30% approx power I am wondering if because I keep my wiring in the side pocket of the battery bag and have to screw with it every time I go to unplug and charge and then replug something is coming loose,a month ago I would have called it crazy but now that I have delved into troubleshooting it seems like most hub motor bikers spend 80% of their time repairing or troubleshooting either melted or loose connections. I was amazed. is it wise to err on the side of caution and solder as many connections as possible to minimize the connection issue these systems experience??
Please Advise
and thank you ever so much for touching on this issue I learned more in just this post than the last 3 days spent spinning my wheels no pun intended
Rob C The Admin
 
Oh also someone here mentioned something about the electric Brake cut off what the heck are they talking about, yes brake levers and wiring came with the kit and yes I installed it, when does the cut off get activated when the levers are closed and the brakes look like they are not working or is it something else that triggers the shutdown..


please advise
Rob C the Admin
 
Well I guess I post here once again one last quick question, going from a 6 wire single loom red green black white yellow brown thumb throttle to a full twist throttle 2 loom one red green black and the other loom yellow and white and the molex on old throttle is the flat black male female type where the twist are 2 white box type molex the with colors i indicated above i am assuming the red green and black are straight forward to the controller and the yellow and white would be what activates the battery levels or phase wires the old thumb has 3 phase i believe full 1/2 full and empty. could someone be so kind as to assist with 1. will this twist throttle even work on this brushless hub motor 48v 1000 watt the controller and battery are labeled mfg SUN and the battery is a LIPO4 the big box type with blue covering Li Ion or Lithium Ion battery. and 2 what colors connects or solders to what colors on the controller... thankyou
 
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