Throttle acting very strange after rebuild

[okie]

I rebuilt my bike to make some upgrades, and after getting everything put back together and all the electronics plugged back in, my throttle is being really weird.

My bike has:

QS205 motor
SVMC 72150 controller
Domino throttle

It went like this:

1. I redid the hall test because I had unplugged everything, so I assumed it had lost its memory. Hall test was all normal, just like when I've done it in the past, no obvious issues. MQCON app said normal and fault free.

2. I go to test it and the throttle doesn't respond on twisting it. So I continue to twist and almost at the very end of the travel the bike groans forward an inch and stops. Throttle is now completely dead, and app is saying system error, fault type hall.

3. I turn everything off and back on again, and the MQCON app is again saying fault free.

4. Try the throttle again, the exact same thing happens.

I triple checked my throttle wiring against the various manufacturer diagrams. It's the same throttle that was working for years. So I don't think it's miswired or that it just happened to go out. I'm thinking there has to be a loose connection somewhere.

I've asked around on FB, and people have suggested throttle, hall sensors, and phase wires; but everyone was just spitballing. I feel like someone who really knows how these things work would be able to narrow down what I should look at first before I start ordering replacement parts/pulling all my wiring out. I'm hoping to get this solved as quickly and inexpensively as possible. I live downtown where parking is scarce so this is my primary transportation down here.

Update: In the MQCON phone app, the main screen is showing the throttle's resting voltage to be .02v.

I have absolutely exhausted all resources checking to make sure the throttle is wired correctly. I've metered out the wires coming from the controller and checked and double and triple checked the wiring diagrams from the controller and throttle, and I can't find any possibility that I've miswired it.

 

[E-HP]

I would disconnect the hall connector and check that none of the pins got bent, or try the second set.

 

[okie]

I would disconnect the hall connector and check that none of the pins got bent, or try the second set.

Would it pass the hall test though if there were an issue with the hall sensors or wires?

And would that somehow also result in my throttle only showing .02v when at rest (read in app and verified with meter)?

I'm not arguing with you, forgive me if those are silly questions, it's just not easy to get to those hall connections on my bike because it's a stealth clone, so I want to make good and sure there's a clear imperative to pull all that apart before I do anything that drastic.

 

[E-HP]

It could be you have more than one thing going on, but both could contribute to no throttle response, so I'd try to clear the error first.
Does the red conductor for the throttle have 5V on it?

 

[okie]

It could be you have more than one thing going on, but both could contribute to no throttle response, so I'd try to clear the error first.
Does the red conductor for the throttle have 5V on it?

Yes, the red wire coming from the controller measures 4.8ish volts when the controller is powered on.

The hall sensor error clears when you turn the controller off and on again, and it passes the hall test without issues. Twisting the throttle induces a hall error, which subsequently vanishes when you turn the controller off and on again.

 

[dominik h]

Normaly the hall throttle is in the range 0.7-1.2 at zero turn and 3.5-4.5 whith full throttle.
With 0.02V there is something wrong. Most of the controllers give throttle errors when the voltage gets out of the range , either around 5V or around 0V.

 

[E-HP]

Can you monitor your 5V supply while you twist the throttle? Both the throttle and halls use 5V, so maybe something is shorting/interrupting your 5V supply, affecting the hall signal. Do you have access to another throttle?

 

[okie]

Can you monitor your 5V supply while you twist the throttle? Both the throttle and halls use 5V, so maybe something is shorting/interrupting your 5V supply, affecting the hall signal. Do you have access to another throttle?

Normaly the hall throttle is in the range 0.7-1.2 at zero turn and 3.5-4.5 whith full throttle.
With 0.02V there is something wrong. Most of the controllers give throttle errors when the voltage gets out of the range , either around 5V or around 0V.

Okay, big update!

I just discovered that simply turning the rear wheel manually will induce a hall error all by itself. The throttle can be completely unplugged even, and just reaching back and turning the wheel with my hand will induce the hall error.

E, you might be onto something, because there does does seem to be an issue with the throttle, too. The throttle isn't producing the right voltage at rest, and it won't move the bike at all unless it's full throttle.

So, yes, the issue does seem to be with the 5v power supply.

Something kind of interesting. Whether moving the motor with the throttle or during a hall test, the motor will turn to a certain point and then lock up and there's a click when the motor stops. I wonder if there's a bad hall sensor and that's what is making that sound?

The problem seems to be getting worse. I was able to complete several hall tests earlier, but now it seems like it's not able to complete a hall test anymore.

 

[E-HP]

If the problem is getting worse, then pumped the brakes and proceed with caution. I'd first test the hall sensors; see the guide by Tommycat below. Doesn't the QS205 have two sets of hall sensors? If so, don't try them yet, in case something with the controller is killing the halls, but I'd compare the wiring of the connectors to make sure something's not screwed up there. Any chance you plugged into the spare?

Testing BLDC motor's Phase Wiring - Hall Sensors and Wiring. - Electricbike.com Ebike Forum

Testing electrical components of a typical hub motor with a digital multi meter. First take a few minuets and look over the wiring going into the motor for cuts, scrapes, missing insulation and other wiring issues or poor connections that should be resolved first. Smell for...

electricbike.com

You probably need a new throttle with that weird resting voltage. You can test it with the guide below, but there's a good chance you'll be replacing it.

Guide to Hall Sensor Throttle operation, testing, and modification. - Electricbike.com Ebike Forum

***** 8-16-2018 Welcome to the Hall Sensor Throttle Thread! If there is something you'd like to add, correct, needs better explanation, or have a question about... feel free to Private Message me. Better yet, open a new thread in the "Trouble Shooting...

electricbike.com

 

[okie]

If the problem is getting worse, then pumped the brakes and proceed with caution. I'd first test the hall sensors; see the guide by Tommycat below. Doesn't the QS205 have two sets of hall sensors? If so, don't try them yet, in case something with the controller is killing the halls, but I'd compare the wiring of the connectors to make sure something's not screwed up there. Any chance you plugged into the spare?

Testing BLDC motor's Phase Wiring - Hall Sensors and Wiring. - Electricbike.com Ebike Forum

Testing electrical components of a typical hub motor with a digital multi meter. First take a few minuets and look over the wiring going into the motor for cuts, scrapes, missing insulation and other wiring issues or poor connections that should be resolved first. Smell for...

electricbike.com

You probably need a new throttle with that weird resting voltage. You can test it with the guide below, but there's a good chance you'll be replacing it.

Guide to Hall Sensor Throttle operation, testing, and modification. - Electricbike.com Ebike Forum

***** 8-16-2018 Welcome to the Hall Sensor Throttle Thread! If there is something you'd like to add, correct, needs better explanation, or have a question about... feel free to Private Message me. Better yet, open a new thread in the "Trouble Shooting...

electricbike.com

There's a really good chance I plugged into the spare. I'm not sure which is the main and which is the spare. I was told originally it didn't matter which one you used.

The one I'm plugged into is the one that has the wire color coding that matches the color coding of the wires coming out of the controller. I just kind of assume that was the primary and the one with mismatched colors was the spare.

 

[E-HP]

There's always that slim chance that they screwed up one of the connectors. I'd just check to see that the 5V conductor is is in the same position on both connectors. I'd do the checks on the halls first, check the throttle, then try the other hall connector.

 

[okie]

There's always that slim chance that they screwed up one of the connectors. I'd just check to see that the 5V conductor is is in the same position on both connectors. I'd do the checks on the halls first, check the throttle, then try the other hall connector.

So for some reason I was plugged into what I think must be the backup hall wires (non color matching bundle) when I took everything apart. I couldn't figure out why I did that when I built it two years ago. I'm wondering if maybe I had trouble doing the hall test back then and someone told me to try the spare and it worked and I never gave it a second thought. I have no recollection of that being the case, but I also wouldn't put it past myself to have no recollection of it. I think it's definitely suspicious that I hooked up to the non color correct bundle because I'm kind of OCD about that stuff and I like for things to match. I have trouble seeing myself having done that without a reason.

 

[okie]

There's always that slim chance that they screwed up one of the connectors. I'd just check to see that the 5V conductor is is in the same position on both connectors. I'd do the checks on the halls first, check the throttle, then try the other hall connector.

Normaly the hall throttle is in the range 0.7-1.2 at zero turn and 3.5-4.5 whith full throttle.
With 0.02V there is something wrong. Most of the controllers give throttle errors when the voltage gets out of the range , either around 5V or around 0V.

I wanted to let you know I found the root of the problem. Two hall wires, connection failed and they were touching. I got them separated and can now turn the wheel without the app showing an error. I think that was it.

 

[E-HP]

I wanted to let you know I found the root of the problem. Two hall wires, connection failed and they were touching. I got them separated and can now turn the wheel without the app showing an error. I think that was it.

Great! Let us know after your road test!

 

[okie]

Great! Let us know after your road test!

I imagine I'm going to be back soon for more help. The reason I tore it apart to begin with was to bring more wires up from the controller to add peripherals. Adding display, ebrake throttle, 3 speed switch, and a full set of lights and turn signals. So after I get it all put back together then the real fun starts. I'm not even remotely sure how the controls, lights, and display all get wired together.

 

[E-HP]

You'll probably find a few threads using the search tool. I don't usually pay attention to that stuff, but I googled "ebike light kits" and got quite a few hits, apparently up to whatever you want to spend.

https://www.amazon.com/Headlight-24-48V-Warning-Electric-Scooter/dp/B0C36XPSJX/?th=1

 

[Kennyken5072]

hi mate been reading about your fault i find knowledge is power and people out there do know the answers but choose not to help.
if this was me my first thing would be return settings to factory and back trace every wire you've touched and check voltages start from battery to converter check you have 72v(example)coming in and 12V out and follow out from there with volt tester its tedious and long, check your earths are tight also all controller connections, oh i have picture of the wiring loom the factory sent me as i have contact at the factory in china which really helps.
i'd also re-set all parameters to factory standard via MQCON app, once you've solved the fault re-map the controller a bit at a time.

When you run hall test you MUST do it in factory style conditions any slight error will result in false readings.
I have all the MQCon manuals and parameter settings and limit settings if you need them also step by step hall testing.
if need anything am happy to try and help as i'm currently re-mapping my stealth bomber rep.
kenny

 

[E-HP]

hi mate been reading about your fault i find knowledge is power and people out there do know the answers but choose not to help.

Maybe not on this case, since he’s resolved this issue and several others since this post, with help the forum Update: now have a fully working light system