Display dead? Diagnose! BBS02


New member
Local time
12:30 PM
Aug 20, 2023
Oceanside, CA
I have the Bafang BBS02b. I've got about 3000 miles on it, its been very reliable. Finally getting around to changing the PAS levels so that:
PAS 1: just enough assist so that it's like a super lightweight bicycle. Because of motor drag it's very hard to pedal with no motor assist
PAS 3: where the original PAS 1 was, this gets me to 18-20mph
PAS 5: 100% power

I was trying the limitless .el Profiles, and had pulled apart the cable from the motor to the display maybe 8-10 times total, and hooked up to my Win11 laptop using Penhoff's modified Calibration tool. I successfully changed and saved the Profile several times.

After my 3d attempt, when I put it all back together, the display was dead! HOWEVER, with the programming cable hooked up from the bike to the laptop, I was able to Read and Write the Flash memory, and a small LED that blinks when the power is on was blinking (the shift interrupt), both of these things makes me think that everything is OK but the display is not reading for some reason.

Display and overall troubleshooting: I'm not much of a mechanical or electrical guy so these are my best uneducated guesses.
1. These control cables are probably made from super thin wire and after unplugging and plugging back in I might have damaged the cable to the display?
2. The display itself is kaput?

My only thoughts so far:
1. Extensive research
2. Buy a new display that has a return policy to see if that's the problem
3. Pull open the display and look around, but this seems unlikely

As you can imagine I've been very upset about this. I'd love to buy a new bike or take it to a shop and have someone fix it, but I live on a very very limited fixed income, so having my main means of transportation go out on me is really rough. Help to diagnose this problem would be much appreciated!