alien ocean aurora help 2

[EddieH]

I have an Aurora that keeps cutting out/switching off, is it the battery or something else?
For a while it would occasionally turn off and I would have to turn the key off then back on and press the On button to restart it. This happened perhaps once a fortnight so was no great worry. Now it is switching off constantly but I just have to press the On switch to restart. Sometimes it is fine and I can get to the shops and back with no stops and sometimes it is unrideable. I thought it might be struggling with my weight but it has switched off when it is just standing in the shed so can't be that.
Any help would be appreciated as my local e-bike shop charges £50 an hour labour which I can't afford and without this bike I am housebound.

 

[Deleted member 4366]

Almost certainly the battery. If you're very lucky, it might be bad solder joints on the back of the key-switch. You don't really need that switch because the battery is isolated by the panel switch, so to eliminate it as a possibility, you can cut the wires off the key-switch and join them together.

You can check your battery by charging it fully, then measure the voltage on the terminals. That will tell a lot about its general condition. Post the results here so we can advise you.

Before the power cuts, what do you see on the panel leds? Do they go down or does it just cut while all LEDs are lit?

 

[EddieH]

Before the power cuts, what do you see on the panel leds? Do they go down or does it just cut while all LEDs are lit?

All of the LEDs are lit when it cuts out.
I have now ordered another battery so hoping that cures it. When I get the new one I will try bypassing the key switch and let you know what happens.

 

[johnc461165]

I have the same bike, cutting out then having to switch off/on is the battery, I had the same problem when mine was 6 months old, a cell had gone bad, the battery was replaced under warranty, you can try my battery if you live close enough John (Wigan)
PS Where did you order your battery from?

 

[Deleted member 4366]

All of the LEDs are lit when it cuts out.
I have now ordered another battery so hoping that cures it. When I get the new one I will try bypassing the key switch and let you know what happens.

I guess you mean that you'll bypass the key-switch on the old battery!

 

[EddieH]

I guess you mean that you'll bypass the key-switch on the old battery!

Lol, yes d8veh, don't think I will mess around with the new one.
Johnc, thanks for the offer but I live in Suffolk so a bit of a travel. I got the new battery from BMS Batteries at https://bmsbattery.com

 

[Deleted member 4366]

When the battery comes, check the polarity of the terminals is the same, otherwise you'll be looking for a new controller.

 

[EddieH]

When the battery comes, check the polarity of the terminals is the same, otherwise you'll be looking for a new controller.

Silly question #2, how do I check the polarity? (not very good with this electric stuff)

 

[Alan Quay]

Stick your meter on volts, DC. Connect it to the two battery terminals. If the result is a positive voltage, then your red lead is connected to the battery positive. If negative, it's connected to negative.

Try it both ways to be sure.

Edit: practice on an AA, or PP3 battery, and don't let the probes touch each other when you test the real thing.

 

[EddieH]

Thanks for the help.

 

[EddieH]

Almost certainly the battery. If you're very lucky, it might be bad solder joints on the back of the key-switch. You don't really need that switch because the battery is isolated by the panel switch, so to eliminate it as a possibility, you can cut the wires off the key-switch and join them together.

You can check your battery by charging it fully, then measure the voltage on the terminals. That will tell a lot about its general condition. Post the results here so we can advise you.

Before the power cuts, what do you see on the panel leds? Do they go down or does it just cut while all LEDs are lit?

Finally got a new multimeter and put it on the old battery (still waiting for the new one) and it reads 49.1v so looks healthy enough.

 

[Deleted member 4366]

I don't think so!. If it's a 36v battery, it's spawned new cells. If it's a 48v one, it's at least 5v too low. Or, it might be your meter that's not too healthy. Try measuring your car battery, which should be about 13v. If the meter's battery in the meter is worn out, it'll give false results.

 

[EddieH]

I don't think so!. If it's a 36v battery, it's spawned new cells. If it's a 48v one, it's at least 5v too low. Or, it might be your meter that's not too healthy. Try measuring your car battery, which should be about 13v. If the meter's battery in the meter is worn out, it'll give false results.

Sorry it's 41.1 not 49.1. It's a 36v battery and a brand new muitimeter with new battery (sorry no car to check it on)

 

[Deleted member 4366]

41.1v is not very good. It should be about 41.4v. You didn't anser the question about whether the battery indicator LEDs go down. What happens to them when you start off with full throttle?

 

[johnc461165]

My battery is past it's best on the same bike, I have a digital waterproof volt meter as recommended by d8veh, ( good buy thanks) fully charged now gives me about 41.6 at best but this quickly drops to 40.1 when using the bike which does me for a few days, after that my bike will cut out even though the meter shows something like 38v.
I guess this is because some of the cells are worse than others and the BMS sees this and cuts off the power to protect the low cells. I am certainly no expert on these things but whatever Dave tells you in my opinion you should take as gospel, he is a star.

 

[EddieH]

41.1v is not very good. It should be about 41.4v. You didn't anser the question about whether the battery indicator LEDs go down. What happens to them when you start off with full throttle?

Starting off with full throttle everything is fine then it will all suddenly cut out and the LEDs go out, they do not go down to 1 bar or anything just suddenly go out. Pressing the On/Off button normally starts it up again.

 

[trex]

it seems to me that your battery is on the way out and there is not much you can do to fix it. Only gurus like d8veh could fix these things.

 

[EddieH]

it seems to me that your battery is on the way out and there is not much you can do to fix it. Only gurus like d8veh could fix these things.

Certainly looks that way, and it is really nice to have someone like d8veh and others who are willing to help us mere mortals out. Thanks all.

 

[Deleted member 4366]

If it's the normal knackered battery, i would expect to see the LEDs go down before the power is cut. Try using just a bit of throttle to see if one or more LEDs go out before it cuts.

It could be that you've got a bad cell in the battery, and the BMS is cutting power when that cell reaches the minimum voltage point (LVC). If you have the capability, you should take the ends off the battery and slide out the contents. You can then access the multipin connector on the BMS to measure the individual cell voltages. You might have to peel off a bit of shrink-wrap to get at it.

 

[EddieH]

Got the new battery and the polarity was reversed (thanks for telling me about that d8veh) so as the connection was different I swapped that over when I changed the connector. Unfortunately the motor just stutters now and goes nowhere and as I have taken the connection from the old battery I cant even use that now. As you may have gathered I don't really understand these things but can't afford to pay my local shop to do it for me.