Bafang M5 Parameter settings mess - only getting 11 amps max output now

[TwisterGripper]

If anyone has come across this issue please let me know if you found a solution.

Display: Bafang M5 display. LCD-M5-27.5
Controller: 9 mosfet 48v 18amp
Battery: 48v 13ah
Motor: Bafang rear hub BFSWX02 48v500w(13)
Gio Bike models Storm and Peak

I have found this problem on 3 ebikes of the same setup (same display/controller/motor/battery) AFTER changing parameter settings for safer output. ( These bikes had a bit too immediate and strong power for some to consider safe)

now very slow acceleration, power feels like its cut in half. display shows only putting out 11 amps max, even on highest PAS setting or using throttle
I had put in some custom power settings for the different PAS levels - to make it safer for the older buyers, I turned pas level 1 & 2 down for lower speed.
I set the settings back to factory original, but the power loss remains…
Tried factory reset (P16, long press 5 seconds) but that did nothing
- replaced throttle on one bike- no change
- full battery - voltage is on spec

Parameter 26 was set to 87, I changed back to factory setting of 41…no change, tried maxing it out at 255 - no change - it is not documented what this parameter is for but 0-255 indicates it should be a current limiter setting just like the pas levels settings. maybe setting for throttle?

- it reaches top speed 32kph ok, but slower getting there, it seems only current output is being limited to 11 amps. even on hill, it hits a hard limit of 11 amps according to display. I know it has more power than this as I have test ridden every one of them that I sold.

here are the parameters (factory original) I went back to:

Code Parameter Factory Values Description

P01 Backlight Brightness 2 Backlig ht level

P02 Mileage Unit 0 Metric=0 Imperial=1

P03 Voltage Class 48 Voltage *DO NOT CHANGE*

P04 Sleep Time 10 Sleep mode timeout time

P05 Power Assist 1 Assist levels 0=0-3 1=0-5 2=0-9

P06 Wheel D 27.5 (peak) Wheel Diameter inches -

P07 (motor) Speed Magnet number Storm 1 Speed sensor magnets- *DO NOT CHANGE -

Peak 6
P08 Speed limit kph Peak 41 Peak: max 41kph - but it still only went to 32kph

P09 Zero / Non-zero Start 1 0 = zero start - Motor & Throttle work even if bike not in motion.

1 = motor & Throttle will not work until bike reaches 6km/h

P10 Drive Mode Setting 2 0=Pas Only (throttle disable) 1=Only Throttle 2=Both PAS & Throttle

P11 PAS sensitivity 3 Pedal assist sensitivity (delay) 1-24

P12 Assist Power Intensity 5 Pedal Assist Start intensity 0-5 or 1=Low 3=High

P13 PAS magnet disc type 12 magnet number 5/8/12 pcs

P14 Controller Current limit 15 Max Amperage limit.

P15 Low voltage value 39 *DO NOT CHANGE* Lower Voltage Cutoff

P16 ODO Zero-Out NA ODO Reset press/hold

P17 Cruise status 0 0: Cruise disabled 1: Cruise enabled

P18 Displayed speed ratio 100 Speedometer fine tuning. Sets displayed speed ratio.

P19 PAS Level 0 1 PAS level 0 enabled, 1= PAS level starts at 1

P20 Protocols 1 *DO NOT CHANGE* 0 = Protocol 2 1 = 5S

P21 PAS 1 CURRENT LIMIT 128 PAS Level 1

P22 PAS 2 CURRENT LIMIT 155 PAS Level 2

P23 PAS 3 CURRENT LIMIT 185 PAS Level 3

P24 PAS 4 CURRENT LIMIT 216 PAS Level 4-

P25 PAS 5 CURRENT LIMIT 255 PAS Level 5

P26 0-255 41 Do not change - gio storm and peak default was set to 41 on one unit I opened. not sure what this parameter does... it goes 0-255 so thinking it is a current setting for something! throttle maybe? tried 255 - no change - low power still.

 

[amberwolf]

My guess is that there is a parameter that you can't see or change directly, something in factory OEM settings not available to the end user on this OEM version of the system, that was indirectly changed by the initial change, either because there is normally a direct interaction between them, or because of a bug in the display or controller firmware.

A factory reset may only change back parameters a user would have access to, to preserve OEM specific settings (that might require external software and/or hardware only available at the factory or the OEM to see or change).

I suspect but don't know that the settings are saved within the controller itself, rather than the display. Does moving a display from an otherwise identical non-problem bike correct a problem bike, both while it is attached and after the original display is reconnected?

If so, it means the display itself can reset the problem if it has never been changed to that.

If it does work but only while the new display is connected, and not after the original is put back, then the settingsa re in the display and replacing the display would fix the problem.

If it doesn't cahnge the problem at all, then the settings *are* in the controller and are not reset by the display.



Also, if this is one of the BESST (spelling?) tool compatible systems, maybe you can use that hardware and software to reset everything.

 

[TwisterGripper]

Good idea, If i come across an unchanged display... I just posted this in hope of finding someone with the exact same issue and solved it.