Ecotric Fat Tire 26" No Motor Drive

[mayhem100]

Hello all, new guy here. Trying to help my cousin with a problem. He purchased a 26" Fat Tire a number of months ago, its still under warranty but there are no service centers or locations anywhere near up that will touch most ebikes, let alone do warranty work on a specific brand, so we're trying to resolve this with ECotric's tech support and while they're nice enough and seem happy to help, we're getting nowhere. This started about a month or so ago, one trip to the next, his bike wouldn't move under power, pedal power only. Checked the battery, its charged and the display powers on and shows data like battery life and mileage (517 miles if that's relevant). Ecotric diagnosed a bad controller unit and sent him a new one, I did not assist with this, so I can't say for sure what was done. Didn't resolve the problem, so they said maybe a bad motor. He brought it to me and I swapped out the motor last night, still no electric movement.

I'd like to start from scratch and first see if the symptoms are familiar to anyone, or barring that, if there is a set of diagrams or assembly/disasembly instructions online somewhere so I can start troubleshooting components. I see the cable that feeds the motor for example, has a bunch of pins (yes, I lined the arrows up on the connectors when I reassembled it), but which pin does what and can I troubleshoot it with a multimeter? What about the throttle controller? Seems like a spring return twister with a simple cable, maybe its just come undone, but the way everything is covered and sealed up its hard to trace where the various cables go to and from.

Anyone have any thoughts? Troubleshooting flowcharts? Wiring diagrams? Some chicken bones and a voodoo doll?

Thanks!

 

[L4rkb0x]

Google for ebike controller pinout

have you got your controller manual?

Photograph your headset, controller labels and leads and any sensors you can identify like the pas or cadence sensor to help us guide you.

i would do something like
1) eliminate battery problems - done,
2) confirm conrtroller/headset coms ok - done? no errors reported?
3) validate control input pas/cadence sensor input and throttle input
pas sensors are generally hall sensors 5v and wil blip on the signal wire when a magnetic field is close by
the throttle should provide a varying voltage between, 2-5v? iirc tho check that..
cadense sensors ?? if applicable look yours up..

if the sensors check out then validate their wiring back to the controller with a continuity test
4) check all wiring for continuity

If you get this far with no probs? wow.. check the controller output, the 3 phase outputs google up on that its hi power so take care.

 

[mayhem100]

Thanks for the reply.

I have only the bike, battery, key and charger and the two motors. I'll have to look for the manual, but apart from 26" fat tire I've got no model info that I can find on the bike.

Happy to take photos. Will start disassembling to look around. Just googled pas and cadence sensors to find out what they are and this leads me to the question, does this thing need to be pedaled for the motor to operate at all or should it run while pedals are stationary and the bike is on the kickstand with the rear wheel in the air? I'm operating on the assumption the motor should work at any time the throttle is applied and there is enough juice in the battery.

1) I'd call this done.
2) I can say that there are no error codes displayed on the LCD screen. I'm assuming any internal diagnostics would automatically show errors on the screen, but is there an onboard diagnostic sequence I can force?
3) next step
4) next next step

Thanks. This is my first exposure to ebikes or troubleshooting any electric powered vehicle, so its all pretty interesting actually.

 

[Bobber]

I have an Ecotric Hammer. The motor will kick in while pedaling or you can just use the throttle. I believe most ebikes work this way. Mine has been perfect, sorry about your troubles. It's for sale because it's too big for me btw, near Seattle.

 

[harryS]

New controller. New motor, Check the brake switches. Just unplug the cable from each laver at the controller. See if bike runs.

 

[harryS]

Generic Ecotric owners manual from when I used to own one. Has a wiring diagram on last page.
.
The display is a stand along device. It will power up with just the battery power and no controller. Power it up and try to invoke walk mode. Not sure on your model, but for most of them, you hold the down button for 10 seconds. Wheel will spin at about 3 mph if successful. The display sends a command to the controller to do this, If the display cannot communicate with the controller, it should flash an error code indicating a comm error,

If no comm error or motor action happens, time to see if controller got powered up, It's turned on by a signal from the display, Take out your multimeter and identify the throttle connector. Three pins. One is +5V. One is ground. Third is signal. Look for presence of 5 volts (actually about 4.5V) on two of the pins. If you get no voltage,
the display is powering up, but not turning on the controller. I can tell you how to probe that if you need it, There are other connectors to check for power, but the throttle is easiest.

 

[L4rkb0x]

Thanks for the reply.

I have only the bike, battery, key and charger and the two motors. I'll have to look for the manual, but apart from 26" fat tire I've got no model info that I can find on the bike.

Happy to take photos. Will start disassembling to look around. Just googled pas and cadence sensors to find out what they are and this leads me to the question, does this thing need to be pedaled for the motor to operate at all or should it run while pedals are stationary and the bike is on the kickstand with the rear wheel in the air? I'm operating on the assumption the motor should work at any time the throttle is applied and there is enough juice in the battery.

1) I'd call this done.
2) I can say that there are no error codes displayed on the LCD screen. I'm assuming any internal diagnostics would automatically show errors on the screen, but is there an onboard diagnostic sequence I can force?
3) next step
4) next next step

Thanks. This is my first exposure to ebikes or troubleshooting any electric powered vehicle, so its all pretty interesting actually.

Im fairly new to ebikes specifically myself everyone was at sometime..
Like yourself it seems im the chap stuff gets dropped off with when it stops working..

just in case.. REMOVE THE BATTERY before opening anything up and poking wires, and take this basic precaution EVERY time you work on the bikes system. tho im sure you knew that already.

Controller manual wise, generally there are 2 versions a quick sheet supplied by the dealer, and a multipage pdf you can probably download via a dealer supplied link or a manual repository.

The larger pdf will detail any error reporting features as well as any configuration options. Worth a read to see if anything needs explicit turning on. And may well include a fault finding guide too. However not all controller display systems are open to user config this may be more an eu/uk issue ?

The manual is generally focused on the display not the controller id so if your display has s900 on it google for "ebike display s900 manual pdf" you might need to look at the display rear, a picture would answer this..

Generally speaking controllers are dumb and the display/headsets are 'smart' so you configure 'stuff' with the display, and when the system starts up the display dumps the relevant settings to the controller.. well thats how i understand it .. and its a generalisation as there are no doubt specific brands that work in very specific ways..

As for how it should operate that depends on how its configured to operate, hence the manuals importance, but generally yes the throttle should start the motor it might be limited to walking pace without pedaling but it should spin some if turned on. - generally..

Pedal assist can take a revolution or 2 of the crank to kick in and is driven by a pas (pedal assist sensor?) or sometimes a cadence sensor (same thing mostly) and is generally enabled by default but might well start off in zero 0 mode, requiring a press of an up button to increase the level of assistance to 1 or greater for it to engage. it might be labeled 'gear' in the display?
Pedal assist levels are often referred to as 'gears'
Some bikes have more sophisticated torque sensors .. doubt this is relevant but if not mentioned your bound to have one..

you swapped motors ? with a known good one? did you really push the connectors together and then push some more?? if one 9 pin 'waterproof' julet connector they can take more effort than you think to engage.

 

[mayhem100]

Yes sir, swapped the motor with a new one sent directly from Ecotric. Connectors are tight.

So I went out and powered it on, lifted the back wheel and pressed the down button for a few seconds. Damn thing started going. Motor goes into "walk" mode at 4.5mph. While doing this I applied first one and then the other brake, as soon as I did, the motor stopped running, which suggests to me that the brake sensors are good and connected properly.

Hopped on and started pedaling and the damn thing started running the motor, very slowly. Ran for as long as I kept pedaling, but I did not have to pedal with force to move the bike, just enough to keep the pedals going, so I guess this says the cadence or pas or whatever sensor it has at the crank is also working. I discovered it has 5 forward speeds and tried them all, each one seems to move the bike progressively faster so I'm guessing this is a cruise control of sorts.

But in no mode I've found yet does the throttle seem to have any effect on the motor, its acting like its disconnected, so I'm off to locate and test the throttle connector next. Hoping its a bad connection, but maybe needs a new throttle control.

Thanks!

Edit: Hooked the original motor up and engaged walk mode, thing started running properly too so I guess we've got a known good spare motor here as well.

 

[mayhem100]

So, I've got the controller out, looking for the throttle pigtail but naturally they're not labeled. I believe its a 3 wire plug though, right? So that narrows it to 2 connectors. One with red,black and white, the other with red, black and green. Neither gives me voltage though, but I'm not sure they would since i have to unplug them to test them, right?

Is the throttle a potentiometer? I get the signal would put out 0-4.5v (or whatever it is), but it obviously can't if i pull the plug out since it wont have hot and ground either. I'm either doing this wrong or there's a different test process, right?

 

[mayhem100]

Got the throttle off the bike and figured out its te one with the white wire, but the wires have no exposed surfaces to test, so I cant do a continuity test to see if I've got a broken wire here. The throttle doesn't want to come apart, at least not without breaking it.

Going to ask for a throttle from warranty and hope that is the resolution. There really doesn't seem to be much else to check or replace.

 

[L4rkb0x]

the throttle is probably fine, the walk mode, throttle upto 6km/h 4m/h is a EU/UK limit so is commonly configured for export to that market, you may find the throttle will work beyond this limit when also pedaling as that is within the eu regs and a feature available with some, not all controllers.

MANUAL? I could hazard a guess at the button combo to get you into at least 1 secondary menu system, but without a manual to describe the interface it would be useless..

whats your lcd display called/labelled? google for its detailed manual and reconfigure your throttle to work as you would like.

 

[harryS]

Throttle is a magnetic chip, powered off 5 volts. Output goes from ,8V to 4.5 volts. Only works with PAS 1-5, Won't work in PAS 0 for safety, If your friend messed with display settings, on some of the displays, you can disable the throttle inadvertantly,

Glad you've made progress. Who sez Ecotric customer service sucks? You got a spare motor.

Bike should run strong on PAS 4 though

 

[mayhem100]

I tried the trottle while in various 1-5 modes and pedaling, so bike was moving on electric at the time. The throttle doesn't seem to do anything at any time or in any mode. The bike has the S900 display and I have a copy of an ecotric manual thanks to the above poster harrys, which contains a factory reset procedure, so I'll try that and if that doesn't work I'll see about replacing the throttle.

 

[mayhem100]

Yeah, factory reset didn't do the trick.

harryS, so I get that the throttle works on a voltage output over the signal wire, what I'm asking though is how can I test for that voltage? When the plug is connected there are no exposed contacts to touch, but when its disconnected to get at the contacts, there's no voltage because its disconnected. Sorry but I just can't see a way around this without some sort of special test pigtail or something.

 

[harryS]

Red, black, white was the throttle on my old Ecotric controller. Red is power. White is input. . THe other three pin is the pedal sensor.
.
If they didn't fill the rear of the connector with silicone rubber, you can usually push a pin into the opening to touch the wires. You can also push a pin thru the insulation although it can wreck the wire. You can always cut the wires on the throttle side too, and shrink wrap them later.
,
Here;s a common problem. The actual contacts in these JST plugs are little barbed clips that often get loose. This one got pulled back and won't make contact. The leads can also fray on the ends, if the connnector has been hanging out exposed to weather.

 

[mayhem100]

Ah, gotcha. Yeah, the throttle side pigtail is sealed in silicone and those are the female ends or the connector, pins are all even in length. The female side is on the controller which is brand new, sockets look ok to me and honestly if I were a betting man I wouldn't put a dime on that being the problem since it would require a similar failure or the prior controller as well.

I pulled the plug out and repowered it though, used my test light to check for voltage on the controller side and I do get power on the black to red connection, so there is voltage coming out of the controller to the throttle. I bet there's either a broken wire or a bad solder joint on the throttle end of it.

Can I safely just run a test wire from red to white on the controller side?

 

[mayhem100]

Ecotric says they'll send a new throttle, but they're currently out of stock and won't have anything for a few weeks.

New info I got last night was the throttle had been loose on the handlebars and he tightened it up. I'm betting maybe too much and it cracked something inside...maybe, maybe not.

I'm tempted to buy one off Amazon and if necessary snip and solder the wires as needed. Assuming the ones on there work at the same voltage settings that is. Is this throttle more or less universal, outside of the pin out?

 

[harryS]

Throttles are cheap and pretty much the same, except for the connector. Just don't go buying one with on/off switch and voltage readout, as that adds more wires, and issues. There's nothing but a rotating magnetized ring and a chip inside. A twist throttle is built the same way.
.
A potentiometer could also work, but is less weatherproof and going to wear out.
.
If you want to test the throttle input, get a pair of 1000 ohm resistors. Put them in series, both ends to 5V and ground. The middle will be 2.5V right? Put that to the controller input and see if it runs motor. It won't work if you just bridge the red/white wires. The white wire has to be less than the red wire in voltage. Or you could use a potentiometer if you have one, and set it in the middle.
.
If you happen to have a diode laying around., you can use that between the red/white wires. Put the end of the diode marked + or with a band on the white. That will drop the voltage by about 1/2 volts and tell the controller to spin the motor at max speed. By the way, if you have a working throttle, and the ground wire breaks, the controller will also spin the motor at full speed. It's happened to me twice.

 

[mayhem100]

This is EXACTLY what I was looking for harrys, thank you.

 

[mayhem100]

Just wanted to complete the thread here.

The new throttle arrived from Ecotric, plugged it directly into the controller in place of the original and sure enough, bike started working as it should.

Spend some time getting the new one onto the bike and routing the cable as best I could. The twist wrap used by the manufacturer is hopeless to reuse, once you unravel it, it starts breaking and won't go back on securely. I wrapped the wire at the handlebar area in some F4 tape and zip tied it all to the main conduit on the downtube and under the pedals. Its all good and secure now, bike works great and has been returned to its owner who hasn't stopped smiling and riding.

As a bonus we now have a spare controller and motor for future potential problems.

Thanks to all for your advice and patience.