Controller or display shot

Bud Baker

I have a March 2015 BBSO2 500 watt installed with 150 trouble free miles until yesterday. I was out for the first ride of 2016 (been on my trike) and almost immediately started getting error 30 code with the motor cutting in and out on PAS1 and display numbers dropping to zero and back to normal display of speed. I checked out all wiring and spedo connection, shut it down and restarted and still happening. Error 30 is a nondescript communications error. Battery fully charged with 55 v. on my multimeter. Now the display will not power on at all. The vendor selling me the unit says it is most likely the controller. Another well respected expert on Bafang says it is the display. I don't know if the display will power on with a bad controller, but I know the unit will not function with a bad display. Do any of you have any advice or experience with error 30 and controller/display issues?
I have the same problem with my 2013 36V 250W BBS01 unit I bought new in August 2016 and also put less than 200 miles on. Like you I got the Error 30 code on my display which then shut down. I contacted the shop I bought it from who advised me to replace the controller. The replacement controller I received is a 25A 500W 36V unit that I asked the shop to reprogram to 18A for insurance purposes. The new controller has a March 2016 manufacturing date (the Bafang factory switched production to a new BBS01/02B model in April 2016 with a redesigned controller housing so it was important to get a replacement controller compatible with my older model) and serial number K5NCROFO203 - a News post on the em3ev site from 21 Aug 2015 describes how the 3rd character in the serial number 'N' means it has the newer IRFB3077 Mosfets which should improve reliability.
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Update: I replaced the Controller which fixed the Error 30 issue and the motor works at all 5 PAS levels. But after I reassembled the bike I got an error 21 showing on the display which is a problem with the speed sensor and means the display doesn't work but the motor still runs. A cable inspection revealed the speed sensor wire had caught in my kick stand and was ripped out of the controller and cannot be reinstalled. Instead of replacing the controller again I will try riding with the Error 21 as someone on Endless sphere said he had been riding for a year with Error 21. I intend to mount a regular cycle computer to register speed and use my big green button kill switch as a clutch to momentarily reset the display before shifting PAS level.
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