Error 50301b

[Hanzzzie]

Anyone ever got the 50301b error?
Assistance get clunky and then system shuts off, had to restart it 10x yesterday...
last time i was able to finish the last 20km without any issue...

it's alot like my first issue after 1400km when the battery was replaced, but i didn't get an error message back then...

 

[Spiff]

Error 503 is Speed Sensor Fault, and may be your error is 503 with suffix 01b.

I'd give a try to the speed sensor location, distance, cable...

I just googled it, and I was wrong, error means:

Your drive unit was restarted unexpectedly.​

50301B – Your drive unit was restarted unexpectedly.

Your specialist dealer is by your side when rectifying the error. Please contact your specialist dealer.

www.bosch-ebike.com

 

[Hanzzzie]

it's a Cube Stereo Hybrid 750wh smart system with speed sensor on the disc brake area. think the issue isn't with that model as it isn't on the spoke?

 

[Mikerb]

If the assist toggles on and off that suggests intermittent inability to pick up a speed sensor signal. It can be caused either by temporary obstruction of the sensor due to dirt or trail debris, or possibly the sensor having moved a little in its holder. The fault code can be a little confusing since the controller will have picked up 2 events....one caused by the other. First, no speed sensor reading followed by a shutdown, then an auto restart as the sensor problem appeared to fix itself.
Despite the issue appearing to have fixed itself I would do a thorough check of the sensor, any sensor cable that is exposed, and the magnet.

 

[Mikerb]

Just to add.....I have had temporary sensor issues twice with different bikes over years of emtb ownership. Fist time was with a Levo and the result was immediate .otor shutdown.......cause was debris blocking g the sensor....2 minute fix. Second time was with a Bosch smart motor bike and result was different.....the motor assist toggled on and off. On that occasion the sensor cable had been snagged and pulled the sensor slightly out of its holder. So it appears different motor firmware react differently to the same fault.

 

[Hanzzzie]

thx, just checked the sensor and it seems to be firmly attached still, cable looks in good shape aswell.
cleaning all connections with contact spray aswell later.

 

[Hanzzzie]

Yesterdays 70km ride was flawless.
Big ooooof!!!

So i cleaned out everything and sprayed all contacts with contact cleaner. In the bottom plastic plate hiding the cables of the cube (which gets filled up with dirt quite easily tbh) there were some leaves and dirt so i suspect that added an easy way for moisture to get to the wiring too...