I have the same car and the same error code. i think the sensor got dirty when my water pump burst; anyway, I am wondering the same things. Hope you got it fixed. I see your post was a long time ago.
My mechanic says the device is telling him that my 1999 Jeep Cherokee is having torque converter circuit problem. The engine light came on then went off and is now back on. How much of a problem is this and can I drive it for a while. And what is this anyway. I called a transmission guy and he did not tell me much.