Help! Hi all, just bought a 'broken' ebike. Some help needed. Falcoln Turbine.

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
Hi

I just bought a 2020 Falcon Turbine ebike. Its currently not working but I suspect its nothing too major. For the price I paid I could split it for parts if it is beyond repair.

Anyway, I got the bike home from buying it. I was told the battery shows charge (1 LED) but the handlebar display doesn't light up. I soon noticed the handlebar display plug had a pin damaged. It'd been forced in, squashing the pin. This may have caused further damage as the female part of the plug (connected to the battery caddy) had smoke marks on it (see attached pic). So I bought a new display panel. Plugged it in and nothing happens. Gutted. Was hoping it was a simple fix.

I notice the battery (generic Hailong style) doesn't give off any reading when I stick a multimeter on the contacts. I took the battery apart and the cells definitely hold some charge (I get the full 36v at some contacts). However the reading from the BMS to the battery contacts (where it connects to the bike) shows no power. This video appears to confirm that I should be getting a reading from the battery pack contacts (as you'd expect). So I think my BMS is broken (this may not be the only problem with the bike). I need to order a new one. Can anyone advise what to get? My BMS looks very cheap (notice the mosfets aren't connected to anything for cooling purposes, also it has no temperature probes). It has sp-m10-033-a01 printed on it but no brand name etc...

Can anyone advice which BMS will work?

Most of the ones I find online (that are 36v) have the 11 pin connection but not the 3 pin connection mine has (connecting it to the power meter/test panel). Its a 36v 10ah battery.

Also why does the battery pack have 5 contacts on the outer shell but only the positive and negative are used? What purpose do the other contacts serve? I appreciate its a generic box and my system doesn't need the contacts, just curious.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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Check that the switch is actually switching, then pull all the multi-pin connectors from the BMS and plug them back in.
 

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
No, those voltages look fine, have you tried connecting your charger? It might wake up the BMS. If you haven't already, check the battery fuse.
Hi, apologies for the delay.

I can't seem to find the battery fuse. Or rather what I think is the fuse may well not be. It has a what looks to be a 30A surface mount fuse from the red wire (at the charger connection point) to the main battery. I checked the resistance across it with my mutlimeter (how you'd normally check a fuse) and it gave me no reading. I got a 30A blade fuse from my car too to clarify I was doing the right thing (got a reading on that).

However I connected the charger and I get a voltage reading at the battery outputs (on the outer shell of the case) when I do that. I get 24.1v. For ref I get 42.5v straight from the charger and 16.8v after the 'fuse'.
 

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
Check that the switch is actually switching, then pull all the multi-pin connectors from the BMS and plug them back in.
Excuse my ignorance but what do you mean by the 'switch'?

I've pulled the connector from the BMS and plugged them back in already. I get a reading on the pins of the 11 pin plug (depending on which pin I select - which makes sense, different voltage depending on how many cell packs are included).
 

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
Hi, apologies for the delay.

I can't seem to find the battery fuse. Or rather what I think is the fuse may well not be. It has a what looks to be a 30A surface mount fuse from the red wire (at the charger connection point) to the main battery. I checked the resistance across it with my mutlimeter (how you'd normally check a fuse) and it gave me no reading. I got a 30A blade fuse from my car too to clarify I was doing the right thing (got a reading on that).

However I connected the charger and I get a voltage reading at the battery outputs (on the outer shell of the case) when I do that. I get 24.1v. For ref I get 42.5v straight from the charger and 16.8v after the 'fuse'.
FWIW I'm going to try charging the battery overnight and checking the voltage at the case contacts in the morning. For the record I did previously charge it but it didn't give me a reading after charging (however this was prior to opening the battery).
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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Hi, apologies for the delay.

I can't seem to find the battery fuse. Or rather what I think is the fuse may well not be. It has a what looks to be a 30A surface mount fuse from the red wire (at the charger connection point) to the main battery. I checked the resistance across it with my mutlimeter (how you'd normally check a fuse) and it gave me no reading. I got a 30A blade fuse from my car too to clarify I was doing the right thing (got a reading on that).

However I connected the charger and I get a voltage reading at the battery outputs (on the outer shell of the case) when I do that. I get 24.1v. For ref I get 42.5v straight from the charger and 16.8v after the 'fuse'.
30 amps will be the main fuse. The charger fuse is normally 5 mps. Are you sure that it's connected to the charge socket?
 

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
30 amps will be the main fuse. The charger fuse is normally 5 mps. Are you sure that it's connected to the charge socket?
I'll attach a picture in a second but the 30a fuse is the orange circled bit. The red wire on far left is soldered to the last cell on the left. Then it goes to the case positive via that 30A fuse. The charger cable (the very thin red one - its actually about half the thickness of the other red wires) is connected here also (after the batteries - so charger to cells goes through 30a fuse). The other charger cable (White) goes straight to the BMS.

For ref Blue cable is BMS to case negative.

I've circled the charger port in purple. There is nothing else here apart from the female charger socket (its a laptop power supply style - not XLR), so no fuses etc...

I've looked all over the rest of the battery and can't see another fuse anywhere. I can trace every wire too so it can't be hidden anywhere.
 
Last edited:

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
OK, progress, of sorts.

I put a 30a blade fuse in parallel across the surface mount 30a fuse. It now gives me a voltage at the battery case terminals (17v) and it didn't before. This dropped slightly as I tried it (16.9v) so probably just needs charging.

Now the real problems. I believe the bike should power up with a battery only half full. I connected the battery to the bike and nothing happened. I still have the battery case open so I checked the voltage across the battery terminals. Nothing when plugged into the bike, but I get a voltage when it isn't plugged in. That seems odd to me.

Need to investigate if the speed controller is ok.

If the battery gives a higher reading after being on charge for a bit then I'll consider that fixed and will fit the 30a blade fuse permanently (or rather a fuse holder so I can always change it if needs be).
 

UnclePuncher

Pedelecer
May 26, 2021
71
1
Nottingham
Thats the innards of the speed controller/battery dock (battery connection on the right). If anything here is broken its not immediately obvious to me. If it was/is I'm not sure I could replace it as the whole circuit is covered in some kind of resin.

Capacitors all look ok (not domed). Can't see any loose wires. If Mosfets are gone I'd not be able to see it (I believe). May have to just buy a new speed controller. Will see how 'fixed' the battery is first though.
 

vfr400

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Jun 12, 2011
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17v is what you can measure when the BMS is switched off. You'll get the true battery voltage by measuring the cell-pack directly. You said that you hd approx 3,6v per cell, which makes 36v overall, not 17v! Did you definitely get 10 cells with those voltages and not 9?

You said it's a Hailong case battery. They have a switch on them, which switches the BMS on and off, but you have nothing like that connected to the BMS in any of your photos. How do you switch the battery on without a switch?
 

Nealh

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Aug 7, 2014
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If Mosfets are gone I'd not be able to see it (I believe). May have to just buy a new speed controller. Will see how 'fixed' the battery is first though.
Test the mosfets whilst the controller is open with no battery power.
Set meter dial to 20k or 200k ohms and probe the Black battery wire at discharge pin against the three thick phase lines you can see on the board in front of the fets, one should see about 9k ohms for each one or at least they should be all fairly close in reading. Any way out of whack (very low) means a fault.
If ok then try again against the Red discharge pin you may or may not get a similar reading but an ascending one on all or may just a 1, as long as none are zero then thee will be fine on this side.