Chrysler Repair: 2000 T&C Engine light & no speedometer, 4 digit numbers, shift patterns

Question
Recently my wife complained of no speedometer response and the check engine light coming on. I drove it around the block, noticed it jumped from first to second gear abruptly once while driving. Came inside and searched on-line for answers. Performed the self-test for instrument panel and speedometer appears to be working during self-test. Can you help me diagnose further? Could it be only a transmission speed sensor? How can I read the engine trouble code?

Answer
Hi Al,
Yes, the output speed sensor is what generates the signal for the speedo and also impacts transmission shift patterns. So that would be suspect. You might get fault codes with the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see if the reading changes to show any 4-digit numbers. If not, then go to an Autozone for a free readout. The output sensor code is 0720. Let me know if get something else.
Roland