Controller or display problem

Hi guys. I have a problem with my bike. When I turn it on, on the display showing only 1 line of battery charge, but battery has 39,5v. And displays 1 line diode is blinking, like showing that voltage is low.

And bike is do not working.(bike have pass pedals system, don't have throttle)

Inside controller diode, blinking: 2 times-pause-2times-pause.... What code is that i do not know. Mb battery voltage is wery low.

What i am shure, that battery and bms are good.
.........
After i charge battery to 41,5v and turn on, displays 1 line stop blinking, just lighting, without blinking.

And inside in controller diode showing: 1blink-pause-1blink-pause.... Maybe it is code that battery voltage is low... And bike is working, but after voltage going below 40v, stops work.

How to fix this, how to make display shows full voltage,

Controller's chip is stm32f031c6t6
Batery 36v(42)
Display key-disp
Bike pollar

Need any help thx.

!. Did you just obtain this bike recently?

2. Has it always done this?

3. Has the battery or controller been replaced recently?

4. Can you set the voltage of the battery on the display? ***

5. Stating the brand name of the bike might be useful.

6. If and when you find a solution, report back here and explain what procedure solved the problem. Also what you tried that did NOT work. This is how the hive mind works. This is also what most people fail to do.

7. Note that #1, 2, 3, and 5 should have been included in your very first post.

1. Bike was obtained 1 year ago.
2. Before he works good, it was no problem with
3. Battery and controller and display original, nothing was replaced.
4. On the display i can only choose lvl of pass pedal system, form 1 to 5 by prea6 up/down. Turn light on/of by pressing up button for 4 second. And see lvl of the battery charge by 5 light diodes.
Voltage of the battery i measure by multimeter.
5. Bike brend is polaris, here is bike:
https://polaris.company/en/catalog/electric-bicycles/polar-pbk-2007s/

Thx, sorry im am new here)

It sounds very much like what would happen with a controller which could operate on EITHER 36V, or 48V, with a corresponding low voltage cutoff.

If the voltage is not selectable, you have verified battery voltage readings and their is no problem with your meter, then either the controller, or the display, or both, is defective.

I would contact Polaris for any possible warranty replacement, use original receipt to verify purchase date otherwise (much earlier) manufacture date will be used.

It is also possible this may be voltage-selectable but only thru a hidden menu which was either accessed accidentally or thru some sort of glitch.

Most likely is controller issue but controller and display must be carefully matched, generally a good idea to order together to ensure functionality.

It may be possible to do a circuit-level repair, but that type of repair is beyond my ability and skill-set.

I do appreciate your supplying all the requested information without throwing a hissy-fit, do please report back with your solution when achieved.