it could be an input sensor, output sensor (your speedo and cruise will not work), solenoid pack (common problem) or valve body problem. oh, it could also be a bad relay or a misadjusted shift cable. I recently had a P700/P1776 combo - and I also have an 02. since there is a TSB stating that the P1776 indicates a problem with the valve body, any solenoid pack build within a certain date range in 02-04 is suspect. so I replaced both the valve body and solenoid pack and I am back on the road. tell ya what, it was no fun when it hit limp mode at 70mph! replacing the sensors is easy and cheap. replacing the valve body or solenoid pack isn't too bad. actually, I found the worst part to be unplugging the stupid wiring connector and disconnecting the shift cable. oh, and only use ATF+4 !!! mopar, valvoline, castrol, and others make ATF+4.