Surron flickers/dies right when ignition turned on

[Mxdwns]

i have pulled the whole harness out of the bike and inspected it. no shorted out wires making contact(that i can see). i replaced the volt converter. didn’t fix the problem. had anyone been able to fix this problem? please help! i have thrown $100’s of dollars at this problem and nothing has worked. bike ran fine and after it sat a couple days it just had this issue. i do have a bac4000. bypass battery.

 

[E-HP]

Did you buy the bike used?

 

[fechter]

When you turn on the key, does it just flash on for a second then go out?

I'd suggest measuring the battery voltage at the controller while turning it on to see if it stays up or drops out.
Do you have the stock circuit breaker?

 

[Mxdwns]

Did you buy the bike used?

yes i did. and i crashed that bike and have built another bike out of parts. boy , i have tried and retried every single wire on the whole bike. bought a new eggrider/ bac4000 harness. i didn’t buy a whole new wiring harness but i have stripped all the wrap on all the wires/connectors and inspected every inch to find or see if anything is shorting out. i rebuilt the plug on the end of the +\~ to the battery. installed completely new +\~ cables. new voltage regulator.

any ideas?

 

[Mxdwns]

When you turn on the key, does it just flash on for a second then go out?

I'd suggest measuring the battery voltage at the controller while turning it on to see if it stays up or drops out.
Do you have the stock circuit breaker?

yes i do have the stock circuit breaker. is that something i should replace? it seems to read continuity fine.

 

[Mxdwns]

yes i do have the stock circuit breaker. is that something i should replace? it seems to read continuity fine.

when i say that it “flashes” it’s the light/eggrider/usb plug that goes on and then fades out quickly and will sometimes kinda fade in and out again all in about 5 seconds

 

[E-HP]

You have a lot going on at the negative/ground connector on the controller, but I’m assuming you already checked that from what you wrote. I would disconnect everything but the battery input and display from the controller to see if it turns on as a troubleshooting step.

when i say that it “flashes” it’s the light/eggrider/usb plug that goes on and then fades out quickly and will sometimes kinda fade in and out again all in about 5 seconds

I forgot to ask, is it only the display that has an issue and the bike runs, or is everything dead?

 

[amberwolf]

when i say that it “flashes” it’s the light/eggrider/usb plug that goes on and then fades out quickly and will sometimes kinda fade in and out again all in about 5 seconds

What is your battery voltage reading, using a multimeter on it's output, while this is happening?

You had another thread last year that was never resolved

Surron cutting out!!!NON-normal problem

2023 surron light bee with x-controller. 100 miles. If I "goose " the gas it cuts out. like it's too much engine strain. At 28mph cuts out. everything stays on just the bike cuts out. key of/on again. where if the rev's low enough it cuts out. its like a certain medium range rev is all it can...

endless-sphere.com

that sounded like a battery problem, to me.

 

[E-HP]

What is your battery voltage reading, using a multimeter on it's output, while this is happening?

You had another thread last year that was never resolved

Surron cutting out!!!NON-normal problem

2023 surron light bee with x-controller. 100 miles. If I "goose " the gas it cuts out. like it's too much engine strain. At 28mph cuts out. everything stays on just the bike cuts out. key of/on again. where if the rev's low enough it cuts out. its like a certain medium range rev is all it can...

endless-sphere.com

that sounded like a battery problem, to me.

I think A-DamW was on the right track on the first reply to that thread, but the OP didn’t know what he was talking about and never performed the test he suggested, which is basically the one you are suggesting now.

 

[fechter]

I've seen something similar when the battery BMS was tripping and cutting off as soon as the bike was turned on.

 

[slaphappygamer]

But I think OP bypassed the BMS. At least I’m pretty sure that’s what they mean when they say “bypass battery”.

 

[fechter]

Right, but it seems like the power is dropping out when it turns on. Could be anything between the cells and the controller (why I mentioned the circuit breaker). Measuring voltage right at the controller battery connection would tell.