PAS does not work but throttle does after KT-LCD upgrade

[spleenharvester]

Hi all, absolutely flummoxed by this so I hope you can help,

I have a Falcon 2022 e-bike that originally had a cheapo unbranded controller + LCD, worked OK but wanted to upgrade it. The motor is a Bafang G010.

First, I installed a KT-15A controller with a KT-LCD4 display. Everything worked fine, including throttle - but PAS does not. It does not even register on the display, so it does not seem to be a problem with the motor. The PAS connector is getting +5V across power and +0.5V from signal to ground when not pedalling, so does seem to be working correctly.

So then I replaced the controller on the offchance it was DOA. Still did not fix it.

So then I replaced the PAS sensor with a KT-V12L. Did not fix it.

So either (a) there's a configuration issue or (b) the KT-LCD4 is DOA. Someone suggested I change C1 to 07 - worked perfectly for 3 seconds, then stopped registering and has not worked since. Also tried C14 to 3, nothing.

Any ideas?

 

[spleenharvester]

So update, I bypassed the display using one of those LCD jumpers - same problem, throttle but no PAS. What the heck is wrong with this thing, did I get 2 parts in a row with an identical fault?

 

[E-HP]

can you post a pic of the connectors between the controller and pas sensor?

 

[amberwolf]

Does it work if you pedal backwards? If so, the magnet ring or the sensor itself may be mounted backwards or on the wrong side. Some PAS sensors are direction-sensitive, and some controllers only work when those are sending the right direction signal.

Distance between sensor and magnet can also matter, if they are separate items. Closer is not always better, so it may require experimentation to get the best distance.

 

[docw009]

I have put in a lot of KT controllers. PAS is a headache.

I recently put one on an ebike with an integrated sensor/magnet combo. So I know there were no orientation issues. Never got it to work, and I pulled an old one out of my box that did work. I heard later from another guy with the same bike that if I had changed C1, it would have worked.

Try C1 at 05, and 06 too. Heck, try them all.

 

[Sturmey]

C1=2 is setting on last kit I fitted by default and worked. (Previous kits had C1=7). Greenbikekit says C1=6 I think as quoted below for KT-V12L. I hope it helps.

Note: This PAS only work with KT controller. Also,Kunteng controller normally set C1 = 2 as a defaullt setting for the 8 pole PAS, if you want to use 12 poles PAS, please set C1 =6 via the display, otherwise the PAS may not work.

https://www.greenbikekit.com/intergrated-e-bike-pedal-assist-sensor-kt-v12l.html

 

[Comrade]

You can't troubleshoot problems without proper test tools. In this case an oscilloscope is needed.

 

[spleenharvester]

Hi everyone, changing to a KT-V6 PAS fixed this immediately. I'm not sure why the KT-V12L and the other 12-magnet PAS seemingly weren't compatible with either KT controller, the number of magnets was set correctly and I tried every C1 value there is (also it didn't work when pedalling backwards). The connectors were also the same.

Cheers!

E: Also just to add the V12L didn't work in headless mode either (i.e. with the LCD connector jumped).