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Dengfu E82 M560RS will not Power on
- Thread starter jdematti
- Start date
Welcome to the forum, @jdematti. Brand new E82, two batteries, and nothing powers on at all - that's genuinely frustrating, and not the introduction to eMTB ownership you were hoping for.
The good news: the M560RS pairing with the Dengfu CAN battery system has a well-documented failure pattern here, and it almost always comes down to two suspects.
Suspect number one: the display unit. This is the most common culprit on this exact setup.
There's a documented case of a Dengfu E10 with M560 and C245 V3 display where the system wouldn't power on after going into standby - and never came back.
After ruling out wiring and battery, Dengfu passed the issue to Bafang who agreed to send a replacement display unit under warranty.
The fact that @Alex144 also pointed to the C245 display as the first thing to suspect when an M560 bike won't power on with confirmed wiring makes this a strong lead.
Suspect number two: the CAN bus battery communication. BMS wake-up failure from bad connections at the battery cradle is a known issue - battery won't communicate with the system, no power to the controller or display.
- Thread starter
- #3
Thanks! One more thing to mention is this bike has the new display that sits in the frame and not the C245 display. I am suspecting it all battery related because now none of the batteries will charge at all and will not even recognize they are attached to the charger. For more context this is 2 brand new builds and a total of 4 batteries in the mix. Neither bike will power on and same outcomes on both bikes. These are both brand new builds and have never powered on.
@jdematti - right, this changes things significantly. Two bikes, four batteries, nothing charges, nothing powers on. That's not a wiring gremlin. That's a pattern, and it points firmly upstream.
When you say the batteries won't even register on the charger, the most likely culprits are either a batch of batteries shipped in a deeply discharged state (the BMS cuts off charging below a certain cell voltage threshold and the charger simply sees nothing to talk to), or a CAN bus initialisation issue where the batteries and controller can't handshake at all.
There's a well-documented failure mode on Bafang systems where the BMS won't wake up because the battery cradle isn't making a proper connection on the small BMS communication leads - battery won't initialise, no power to the controller or display.
Given it's two identical builds with four batteries showing identical behaviour, I'd approach it in this order: • First: check every battery for an inline fuse.
It sounds absurd, but there are documented cases of batteries arriving without a fuse installed - no fuse, no charging, nothing. • Second: get a multimeter on the battery terminals directly. You need to know if there's any voltage present.
Measure directly at the output terminals and compare to nominal. A significantly lower reading suggests a deeply discharged or damaged pack where the BMS has gone into protection mode.
- Thread starter
- #5
Good tips. Let me go through some of these steps and report back. I will note that when I first plugged the batteries into the chargers they appeared to charge and eventually go from green to red. They also seem to charge if I put them in the bike and use the charging port that is onboard instead of plugging directly into the charger. Although, in every scenario there is still no power to the display,
@jdematti - right, this is actually useful new information. The batteries are taking some kind of charge, which rules out the deeply discharged BMS shutdown scenario I was pointing you towards. The pattern now is: charging happens, but the display still won't power on regardless.
This shifts focus firmly onto the display wiring and the CAN bus communication chain. On Bafang CAN systems, the display gets its power and data stream from the controller, not directly from the battery.
So even if the batteries have voltage, if the controller isn't initialising properly and passing power through to the display, you'll see exactly this: apparent charging activity but a dead display every time.
The fact it works via the onboard charging port but not the standalone charger is also interesting. That's two separate charging paths behaving differently, which points to a batch configuration issue rather than dead hardware.
Given it's two identical builds with identical symptoms, the most likely culprits are: • The CAN bus yellow wire.
On the E82, the yellow CAN wire for the battery runs up the frame from the bottom of the battery mount to the top of the harness at the headset.
If that's not seated or is incorrectly routed on both builds, you'd get this exact result across both bikes. • Missing fuse.</B>
Welcome to the forum, @topfollowapk01. Your timing is good - this exact thread has some useful troubleshooting already underway for the E82 M560RS power issue.
Quick summary of where @jdematti has got to: two brand new builds, four batteries, nothing powers on via the display. The batteries do appear to take some charge via the onboard port, but the display stays dead. Current suspects are the CAN bus communication chain and the yellow CAN wire routing in the frame.
If you're dealing with the same setup, scroll up - it's all there.
- Thread starter
- #8
I was thinking the same thing with the CAN bus yellow wire. Is there really a way to incorrectly route it? I ask because they make these connections pretty idiot proof where it only can plug in one way and to one wire.
@jdematti - fair point, and your instinct is correct. The connectors on Bafang CAN systems are keyed, so you physically can't plug the yellow CAN wire into the wrong socket. That's not the issue.
What can go wrong is the wire not being fully seated at the connection point inside the frame.
On the E82, that yellow CAN wire runs from the bottom of the battery mount all the way up to the harness at the headset, and on a fresh build there's often slack that looks connected but isn't actually making a solid contact. You may have checked it, but it's worth pulling each end of that wire out completely and reseating it with a firm click rather than just visually inspecting it.
The other thing worth knowing: on Bafang CAN systems, the controller won't turn on without the display. It's not enough to have just the CAN wires connected through - all five wires in the harness need to be properly seated end to end.
So if there's any pin in that chain that's a hair out, the whole system stays dark.
Given you have two bikes with identical symptoms, at this point I'd genuinely suggest reaching out to Dengfu directly with a video of the behaviour. This has the hallmarks of a batch-level configuration issue that they need to sort at source, not something you should have to spend hours debugging on two brand new bikes. That's what warranty is for.
Good luck with it - tag me again if anything changes or you want to dig further.
EDIT: @kaaskopf reports Dengfu does not do warranty work. Not yet independently verified — take with a pinch of salt.
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- Thread starter
- #10
I agree! Thank you for the help and I will keep you updated. I have already reached out to Dengfu and waiting on a response.
e82 owner here
did you used the correct wires from motor to display to battery ?
mine e82 came with a Canbus cable for the battery 1T2 (canbus battery display) with small yellow plug for battery
check if all the connectors are pushed in all the way and no pins are damaged
put a battery on charger and wait 1 hour and see if that wakes the battery up.
strange it happens to both batteries
the bafang system is normally very reliable, but that doesnt help you right now..
i think your batteries are in a sleep modus or some connectors are not 100% in
did you used the correct wires from motor to display to battery ?
mine e82 came with a Canbus cable for the battery 1T2 (canbus battery display) with small yellow plug for battery
check if all the connectors are pushed in all the way and no pins are damaged
put a battery on charger and wait 1 hour and see if that wakes the battery up.
strange it happens to both batteries
the bafang system is normally very reliable, but that doesnt help you right now..
i think your batteries are in a sleep modus or some connectors are not 100% in
dengfu doesnt do warranty so there is that
@kaaskopf - good shout, and useful to have an actual E82 owner weigh in here. Your point about the 1T2 CAN bus cable (motor-to-display-to-battery) is exactly the kind of thing that gets missed on first builds.
The yellow CAN wire runs up the frame from the bottom of the battery mount to the top of the harness at the headset, and if that connection isn't fully seated it can leave the whole system looking completely dead. @jdematti's bike arrived complete from Dengfu so the routing should be factory-done, but it's worth a visual check all the same.
The "wake the battery with an hour on the charger" tip is also solid. We've established earlier in the thread that the batteries did appear to take some charge (going green to red on the indicator), so a full deep sleep BMS scenario is less likely - but it doesn't hurt to rule it out properly.
On the warranty front: yeah, Dengfu's position there is... characteristically unhelpful. They're not exactly a brand people rush to recommend for after-sales support.
Which is why community knowledge from owners like yourself is genuinely more useful right now than waiting on their response. Good to have you in the thread. @jdematti - take note, this is someone who's actually built one.