Engine light came on, the speedometer stopped working and the car no longer shifts into high gear - 2000 Concord

If your speedometer stopped working and stays at 0 MPH, you should have your car checked ASAP. The most common causes of a speedometer that stopped working include are a faulty speed sensor, a broken gear on the speedometer, damaged wiring, or a faulty engine control unit.

these vehicles have alot of problems with the tcm( tranmission control module) internal failures of trans speed sensors. your car is currently in "limp in mode" to protect your trasmission!!!

It may be your speed sensor. When the speed sensor is not working, the speedometer will not work, the car will not shift past second gear, and the engine light should appear.

Chances are the check engine light came on also. You should have the vehicle scanned for codes, it could be that the output speed sensor has failed. This could put the transmission into limp mode (second gear) and cause the speedometer not to work. I would guess this to be an inexpensive repair, .6 hours labor plus the cost of the sensor, $16.99 at O'reillys ...I hope this helps

A common issue are the input and output speed sensors.When bad they cause the vehicle to go into limp mode keeping it in second gear and speedometer sometimes no longer works.

http://www.youtube.com/watch?v=HPvX190txvk

you need to scan this truck if you have a vss input to the computer then you have a bad trans or a bad vss sensor if no input you should also check the trans range sensor with the scan tool

Check the output sensor on the transmission,
With out a speedometer the transmission does not know how fast you are going or when it should shift

Does the speedometer work?

Your issue is a bad "speed sensor". Your speedometer is controlled by a sensor in your transmission, and when it quits working your speedometer will not work, it can cause very irregular shift patterns and slipping. Replacing your speed sensor should resolve your issues.

I hope this helps you, and I wish you luck on your repair.