Help with PAS connection to KT controller for old RLMartin ebike


Local time
1:51 AM
Mar 7, 2021
I have an circa-2012 R Martin ebike (36v14ah 500W TDCM motor, built in Texas) that I am trying to upgrade to a modern controller and computer. The battery finally went caput and I decided to upgrade while I'm at it. I'm trying to keep as much of the old hardware and wiring that I can as these bikes were built very well.

I'm trying to connect the PAS to the new KT controller - the controller uses three wires, the current PAS has FOUR wires. I can't find much material on how the R Martin bikes were wired and there is no identifying info on the PAS. I figure if I can find the + and - wires, I can put power on the device and rotate it to a magnet to find the wire that is supplying signal. That's my theory anyway.

Here's a photo of said connector, four wires red, yellow, orange, brown

Does anyone have any idea which wires it might be - maybe someone has experience with this manufacturer? Here is a link to the bike (I think it's interesting that the website still exists but no one is monitoring the email addresses on it): R Martin MiPower Electric Bike.

The new controller is a KT36/48v model (KT36/48ZWSRM-NBP03X) if it is of interest.

Thanks for the time and Cheers!

EDIT; I said 2017 but this bike was manufactured in 2012!
PAS controllers are cheap. Get a new one that is compatible with your controller.
Thanks for the reply, and for the most part they are. I'm trying to reuse as many of the components as I can, with the exception of this device, all of them so far. I also want to avoid removing the crank to install a new PAS (I know about the one that splits into two parts so you don't have to do this - don't want that solution). I'm going to try to figure this one out. :)
Prior to cutting the wires, I took photos and labeled the wires. It appears that the pinout on the controller's motherboard are:
Pin 1: Orange
Pin 2: Yellow
Pin 3: Red
Pin 4: Brown
There are two other wires here that come from the PAS computer (blue and black). Blue is next to Orange and Black is next to Brown. So, from left to right - Blue, Orange, Yellow, Red, Brown, Black. I mention these as they may be indicative of power and ground/signal but I'm just guessing.
I could have these backwards but i'm going to play with a multimeter soon to find out.

The new controller is wired:
Pin 1: Black -
Pin 2: Red 5v
Pin 3: White Signal
I highly recommend the KT PAS sensor that presses directly into the LEFT side bottom bracket.
These are small, discrete and have more magnets in them which makes them more accurate.
You can remove the left crank and have it installed in 2 minutes tops.
Set your KT controller parameter C1=7 "12 Magnet PAS". DONE.

You can find them for 10 bucks or less on AliExpress or eBay.

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