Power cutting out

[vfr400]

It has at least two extra pins connected for whatever reason. They go to pins LA1 and LA2. It's not possible to say whether they're used. The only way to be sure is to open the battery and see whether the corresponding pins have wires on them and where they go. It could be a temperature sensor or comms.

The problem is that if it's comms, the battery won't switch on without an instruction from the controller. If you substitute the controller for a normal one, it won't get the instruction. That's still not the end of the game, but you'd have to do some jiggery pokery to sort it.

 

[Nellie]

Ok thx vfr400 . I’ve taken a gamble and ordered a new controller from TranzX . If it’s not that well I’ll have to sell it on eBay to recoup some money

 

[cyclebuddy]

the battery won't switch on without an instruction from the controller.

A really detailed/brilliant post on how to re-cell the OP's TranzX BL07 battery - complete with all internal pics (@vfr400 I think this is what I meant originally).

Note the FREQUENTLY REPEATED instruction to reset the BMS after re-celling. I'd say it's worth a try?

"On the PCB they are connected to RSTN and GND. They need to be shorted for a short time to reset the BMS."

"2 orange wires connected to the load (pin 2 and 5) are connected to the circuit board (ReSeT and GrouND)."

"RST and GND must be decked for a few seconds to reset the capacity/voltage of the battery as seen by the controller (if cables present). For the record, the BMS communicates to the controller the number of loads performed and the current capacity."

"On the BMS, reset the remaining capacity by making a bridge over the 2 orange wires (RST - GND)."

Cyclurba, le vélo utile

Cyclurba, c'est tout sur le vélo moyen de transport urbain. On y parle donc vélo, équipements, réparations, manifestations, clubs, mais aussi de vélos électriques, les fameux VAE (vélo à assistance electrique).

cyclurba.fr

 

[vfr400]

A really detailed/brilliant post on how to re-cell the OP's TranzX BL07 battery - complete with all internal pics (@vfr400 I think this is what I meant originally).

Note the FREQUENTLY REPEATED instruction to reset the BMS after re-celling. I'd say it's worth a try?

"On the PCB they are connected to RSTN and GND. They need to be shorted for a short time to reset the BMS."

"2 orange wires connected to the load (pin 2 and 5) are connected to the circuit board (ReSeT and GrouND)."

"RST and GND must be decked for a few seconds to reset the capacity/voltage of the battery as seen by the controller (if cables present). For the record, the BMS communicates to the controller the number of loads performed and the current capacity."

"On the BMS, reset the remaining capacity by making a bridge over the 2 orange wires (RST - GND)."

Cyclurba, le vélo utile

Cyclurba, c'est tout sur le vélo moyen de transport urbain. On y parle donc vélo, équipements, réparations, manifestations, clubs, mais aussi de vélos électriques, les fameux VAE (vélo à assistance electrique).

cyclurba.fr

View attachment 36913
View attachment 36914

It's already been shown that the battery isn't cutting off, so A BMS problem isn't very likely, but if it turns out that the battery has got comms, then maybe it's telling the controller to stop rather than cutting out. I think it's worth opening the battery to see what's connected. If it's got comms, that procedure should be tried.

 

[Nellie]

Hi cycle buddy
thanx for that link very informative post. I could just about manage to read thr french post.Onthe German Pedelecs site I used google translate and it gives a clearer explanation for resetting. If the bms is disconnected it goes into safety shutdown and needs resetting to turn power back on and display battery capacity. I have all that info on display so maybe the German company who I used did the reset they said they ve been recelling TranzX batteries for years.
vfr 400 given the above account do you still think I should check internal battery connections. I confess I’m a bit nervous playing around in there I’ve just spent over £450 having it recelled.

 

[cyclebuddy]

The post comments the orange wires (connected to pins 2 and 5 of the charge connector) are for connecting to a battery analyser to report cycles and capacity. There's a button battery on the BMS keeping something alive even when disconnected - likely a memory chip. If the Germans didn't reset it, it's likely remembering the battery is knackered.

As always, follow VFR's advice. He has years of real-world practical experience and knows what he's doing. I'm just guessing/commenting on what I've read elsewhere.

 

[vfr400]

I don't have any experience of these batteries, but I know how most ebike systems work.

I think it would be worth opening the battery to see whether it has additional wires on the connector. If it doesn't, at least you know that it's not a battery problem. If it does, you can decide what to do next..

I always try and use logic to solve problems. If you had the symptoms you have now before you re-celled the battery and you were hoping that the re-cell would solve it, then the cause is not likely to be in the battery. On the other hand, if these are new symptoms that came after the re-cell, it's logical that it's something to do with the battery. You checked that the battery isn't shutting down. That only leaves the controller, but we have to answer why.

 

[Nellie]

Thx for the help guys . I bought these parts second hand from various sources on eBay .This was before discovering this site. I assumed it would be easier for me to do it this way as I have no knowledge of the kits and what bits were needed. It became my lockdown project. As always buying second hand comes with no guarantees the battery I bought knackered with the intention of having it recelled . All parts are available for purchase still so as I have spent close to £2k with the tandem and lots of accessories and electric kit,spending another £150 to get it working is ok. The gepida tandem with Bosch mid motor is close to £4K without all the accessories I have so I’m not too despondent just frustrated I can’t get out and use it yet. Controller is coming from Germany could be 7 to 10 days fingers crossed it fixes it

 

[Nellie]

Update thx for all the help people turns out it was the display unit. everything is now working perfectly. So happy off to pub for lunch 2mowith missus