Error code 12 bafang BBS02 850c display

Yesterday it was heavy snowing, I drove slowly, speed 1, 10 km per hour and with 55V voltage. When the bafang motor suddenly stopped after holding. I got no wrong info on display, the morning after when drying up the wet. I received error code error code 12. What would be the problem?

I look to the error codes in the screen menu, I power up, but no error more, the motor still not working and in the advanced menu no error codes! Empthy.

I opened the controller and it contained water, dried and closed again. Connected the motor turned. Everything connected again. Power up, engine no longer rotated. Again controller open and checked again. And connected again, works again. Run the motor for a while. Reconnect everything, start up, nothing again. All connections removed, only power and main cable. Nothing more, sometime it starts and than stops, but now nothing more.
I shall now check the resistance.

I have for a night warming up the motor and the controller open and the next day it worked again. Thanks for the help

I have with this motor a lot of problems
I start the motor again to go to work this morning, I get always error code 3? Error code 3 do not exist in the manual?

After search after the fault and restart, change nothing I get error 4?
Then I change the throttle I get error 30.
I have to push very long on start button before the display starts.

I saw that the gear sensor led going red en green, I removed the connector, nothing

I removed the break and the weel sensor connectors.
Nothing!

I removed the other connectors and blow some electronic spray on it and reconnect.
Nothing?

No error codes no more?

The power indicator on the dpc14 is normal full and green, now it is blanc, like it is empty.
But he gives 61.5V!
I changed a other battery the battery give 59V but the indicator stay empty!

I see also that the wheel pass indicator red led is not working when the magnet is pass.

This engine is so unreliable.

What can I do?
Is it the display, controller or what?

And bafang do not react on mine problem requests!

Do you solved your problem?
Could you describe what was reason?

The best upgrade to my BBS02 I ever did was scrapping the integrated controller for an external 25A Infineon tucked up behind the seat. I killed 2 of the Bafang ones in winter riding, I suspect the seals don't perform well below a certain temperature.

After reducing the system to controller, throttle and motor with no display, speed sensor, gear sensor or anything that doesn't make it go, I have had zero failures or problems of any kind related to the drive system in almost 2 years. I ride well over 1000 km most months.