Limp mode should reset after every cycle (engine restart), if it finds the same condition it will reset limp mode. It locks you into second gear. You can check trans fluid and the EATX fuse & relay to start with, typically you'd have to run the Chrysler DRB scan tool to find a cause. (Could be it needs a new solenoid pack, but could be any number of bad connections between the trans control module and sensors.) FYI most transmission problems won't appear as a trouble code in OBDI or OBDII system.
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