SPEEDO INOP,TRANS IN LIMP MODE,WITH NO CODES

I'm guessing electrical fault or electronic component failure (camshaft position sensor, etc). I've seen similar before on another vehicle I owned years ago.

Has to do with the transmission. Can be wiring/plugs from the PCM to trans, wiring inside the trans, or a solenoids inside the trans is shorting out. Have the codes read. Check the trans fluid also. When it gets low, it can cause a pressure code. This will throw it into limp mode.

any time vehicle trans codes are present, vehicle will go into limp mode. speed sensor mailfuction can cause speed o meter and shift operation problems

it may not be a transmission problem. have you checked for fault codes to make sure it is not in limp mode? limp mode keeps vehicle from accelerating properly because the ECM has put the system at a limited setting to keep the engine running but not to its full potential.

The EMC detected and problem so it's in limp mode, As long as it's in limp mode the 4th and OD will not activate. Take care not to burn up the transmission by running it hard while your in the limp mode.
Your going to have to get the truck scanned to clear any codes and why there are DTC codes. Auto Zone scan for free and most auto shops charge $10.00 to $20.00 to scan sine they want the business.
If you want to clear the codes your self you can put the ignition to the run position and pull the ECM (Batt) fuse out for 20 sec and place it back in then start the truck. It may stall but let it, just start it again and this would have cleared all the DTC code history.
The transmission should be running fine unless there is a problem and the service engine light will be on again and you'll be in limp mode still with an updated DTC in the ECM.
Good luck and hope this helps.

2002 has a known solenoid problem. The solenoid pack must be a new type. They have dates printed on them. make sure it has a date after 2003.

it sounds as though your transmission input and output sensors are faulty.they are located on the driver side of transmission.input at front of trans.output at rear of transmission. normally if input sensor is faulty trans will stay in limp mode. if output sensor is faulty speedo will not register. they both resemble temp sensors with elec connectors

It may be a faulty speedometer with a short inside, or a short on speedometer wirings or connector.

Whenever car vibration cause the wiring to short, there you lose speedometer and trans functionality.

You need to access the speedometer connector and wirings to
instrument panel to fix this.

I would have the transmission shop check out the transmission.
The transmission may have a soleniod issue.

Have u checked w/ scan tool for codes? If not, have garage, dealer, or parts store (free service at most parts stores) check for stored codes, and as u know, Chrysler is known for their c_rappy trannys,. I just had mine rebuilt at 125k (I changed the fluid and filter every 30k, but still failure). Limp mode is to protect from further damage, so something is going on. If no stored codes, drop the trans pan, check for metal in pan and on magnet, color of fluid, burnt odor? Let me know what u find. good luck