Quite a few motors these days have non-replacable sensor cables. Most notably the Novak SS series. Mess up a cable, and you'll be paying more than $30 to send the motor to Novak and get the cable fixed. More if your not in the US.
DISCLAIMER:
I am in no way affiliated with Novak, and I do not take any responsibility for any damage to any motor resulting from this tutorial. Only attempt to repair a motor if you have advanced electronics knowledge and soldering skills.
Materials:
-A new Sensor Cable
-Assorted hex drivers for taking the motor apart
-a soldering iron, prefferably 25w or less with a small PCB tip
-40w+ iron with a large flat tip, like something used for soldering cells together.
-1 small zip tie, color doesn't matter.
STEP 1:
Remove your motor completely from your car (unsolder the leads) and unplug your busted sensor cable. Using the appropriate size hex, remove the front endbell from your motor.
Pull the rotor out, and SAVE THE SHIM!
STEP 2:
Time to remove the rear plastic cap. Just like the front, take out the three screws and gently pry the cover off with your fingernail.
STEP 3:
Time to remove the solder tabs and fiberglass plate. Using your large iron with the flat tip, melt the solder on one of the connections and pry the fiberglass plate up with an exacto knife. You'll have to do this a few times for each of the three connections. Just like soldering a battery pack, only allow the iron to be in contact with the solder puddle for three seconds at a time. The metal tabs transfer heat extremely well and will separate from the fiberglass plate if your not careful.
Remove the black plastic rear bearing holder. Be careful with the sensor wires.
Here's what the hall sensors and thermal sensor PCB look like:
STEP 4:
Remove the PCB from the black plastic housing. There are two small silver screws that hold the PCB to the rear housing. At this point, you should clearly be able to see where the sensor wires attach to the PCB, and you should be able to tell if you have the ability to solder these wires or not.
That's all I have for now, Im going to wait to remove the existing wires until the new sensor cable comes in the mail.
Thanks!
Jon