So I've taken my ZMR250 for a flight or two and had a blast until I crashed. 

After that I noticed, that my my ESCs don't brake anymore. I'm running DYS SN20a with BlHeli 14.7 (that makes them BL20a I guess ). Anything else seems to work just fine! Didn't change anything on the setup! Quad still flies fine though you notice that it does not actively brake, after landing props spin just a little more like they used to when braking was off (motor stop on).

What I did to troubleshoot: 

• disabled/enabled Damped Light --> no braking
  
• reflashed 14.7 --> no braking
  
• flashed 14.6 --> no braking
  
• reflashed 14.7 again --> no braking
  

Visually all four ESC seem to be fine and, as said before, work well.

I think it's normal for the props to spin a little bit upon landing. I would assume that the active breaking works when there is throttle applied and you're changing directions.

This sounds like my blheliS escs when "motor stop" was set to off. The braking worked fine, but when disarming, the motors was freewheeling to stop. Did you recently flash blheli 14.7? The reason why I ask is because I think that the motor stop option was introduced on a later revision of blheli, so it could be that is what happening. Make sure damped light and motor stop is activated. Then try your quad without props and see if it brakes when throttling up and down if you haven't done it already

Didn't flash it recently, I have flown with it for a at least three weeks or so. One thing I've found though was that one motor failed. Changed that but still braking doesn't work as before. Very strange.

Have you checked the motors without props? I'm just saying since from my understanding you are stating that active braking is not working due to the props not stopping fast when landing, am I right? Could you post a video of them when you throttle up/down and disarm? I would think that the quad should fly considerably worse if active braking is not working as it should

When I remove the props they don't really stop at all. Braking didn't stop like no braking more like only 50 or even just 40% of braking power than before that crash. The crash itself was not that hard (maybe from 5 meters or so into the ground). It's just weird. 
Thanks for you help anyway!

Yeah, could be that something happened to your escs.
I know I might be a bit annoying now, but could you please post a picture of your blheli settings? No offence but I am a bit curious because I feel your information is not completely consistent: " that it does not actively brake, after landing props spin just a little more like they used to when braking was off (motor stop on)"

If Damped light is activated it should not matter if motor stop is on or off as motor stop on/off only brakes and stop the motor when you disarm the quad. Damped light is what activates the motor braking in the air.

(24-Sep-2016, 09:15 PM)oyvinla Wrote: I know I might be a bit annoying now, but could you please post a picture of your blheli settings? No offence but I am a bit curious because I feel your information is not completely consistent: " 

I'll post my settings tomorrow. I know I'm not always good at articulating myself.

What I can tell you: Damped Light is on -> motors should brake and motor stop is activated which means that my motors don't spin when armed.

Ah, now I think I understand. You are talking about the motor stop feature in cleanflight/betaflight? If so, what I am talking about is the motor stop feature in blheli. When motor stop in blheli is set to off, the motors freewheel to stop when disarming (since you have motor stop activated in cleanflight/betaflight I would guess they will freewheel when you let go of the throttle). When this setting is on, the motors stop instantly when disarming (or in your case, put the throttle to the lowest position I would guess)

(24-Sep-2016, 09:42 PM)oyvinla Wrote: Ah, now I think I understand. You are talking about the motor stop feature in cleanflight/betaflight? 

Yes!

I just had to look and this feature was turned off. I just checked my last backup and it was turned ON in blheli! Checked my backup before flashing and reflashing and so on: braking was OFF in blheli. WTF? How did this happen?

That's the magic of electronics, they seem to live their own lives sometimes

Have you checked the Brake on Stop in BLHeli settings?

Ah, yes, brake on stop was the setting I was talking about

LOL my everything seems to be fine now. Somehow after enabling "brake on stop" braking works siginificantly better in mid air (even with airmode on!).
Not very logical though. Thanks for all the help!