Help needed: PAS not working on AKM-100H / KT T06S Controller (Throttle works fine)

[glerner]

Hi everyone,

I recently converted my Bike Friday Diamond using an AKM-100H (36V 350W) front motor and a KT T06S (17A) controller with an LCD8H display.

The Issue: The motor works perfectly with the throttle and in walk mode, but the PAS (Pedal Assist) does not kick in at all. It worked for about 200 meters after the first installation and then stopped.

What I’ve tried so far:

• I replaced the PAS sensor with a brand new one (KT-V12L), but the problem persists.
• I’ve tried several combinations of settings in the LCD parameters (C and P settings).
• Checked all waterproof (WP) connections and pins.

Does anyone know the specific C1 and C4 values for the KT-V12L sensor? Is it possible that the controller's PAS circuit is fried even if the throttle still works? I'm reaching a point of total frustration, so any technical insight would be greatly appreciated!

 

[harryS]

The KTV12L goes on the left side. The LCD8H manual says 07 should be used for C1. C4 affects how the throttle works and matters most if you want throttle at PAS0. If PAS doesn't work, try spinning the pedals backwards. If PAS comes on, then the sensor needs to be flipped around.

The main concern with PAS sensors is whether the connector pinout is the same as the controller. Since the KTV12L and T06S are both made by KT, they should match. With a one piece sensor, then it's a matter of spinning the disk in the right direction, I don't recall if the KTV12L has an arrow on the disk.,

 

[glerner]

The KTV12L goes on the left side. The LCD8H manual says 07 should be used for C1. C4 affects how the throttle works and matters most if you want throttle at PAS0. If PAS doesn't work, try spinning the pedals backwards. If PAS comes on, then the sensor needs to be flipped around.

The main concern with PAS sensors is whether the connector pinout is the same as the controller. Since the KTV12L and T06S are both made by KT, they should match. With a one piece sensor, then it's a matter of spinning the disk in the right direction, I don't recall if the KTV12L has an arrow on the disk.,

Thanks for the suggestions! I actually managed to get it working. After riding about 300 meters, the display finally started showing the assist levels and everything seemed fine.

However, suddenly the display just went black and the whole system shut down. I checked the battery and it’s perfectly fine (fully charged and showing voltage), but now I can’t get it to turn back on at all.

Do you think the controller and the display just died, or could it be a failure in the display itself? Any tips on how to figure out?

 

[harryS]

All KT displays, and many others (not my bafang though) , use this wiring on the 5 pin connector. Substitute your bike's voltage for 36V.

If the display doesn't light up, then test for battery power on the two power pins. Power and Ground on the connector on the right. That's all that is needed to power up the display. They will power up with only the power leads. You can test the power leads with pins inserted into the two holes on the female connector. Tape them up so they won;t short circuit,

If you have power, then the display might be bad. If you don't have power, something is wrong with controller's power feed. Check power connector, Check battery.

Do be careful when battery power is involved. If you short circuit it to some other pin,, big sparks, melted pins, blows up controllers.

If you're adventurous, KT displays can be rigged to run w/o a display. That will show whether the controller is OK.

(credit to curt welch for the picture, 10 years ago,)