My 05 Pacifica went into "limp in" mode which means it is stuck in 2nd gear. I took it to AutoZone and put it on the code machine. It pulled up P0700, P0715, P0731 and P0733. I changed out hte Speed Sensor Input and Output and still have the same problems but now it only pulls codes P0700 and P0731. Anyone have any ideas? The speedometer and Tachometer all worked before and after the speed sensor change.

Shift solenoids were stuck on. This could be caused by several issues. Speed sensor could be bad, throttle position sensor could be bad, etc. This is causing the car to go into "limp-in" mode. This causes the transmission to remain in 2nd gear to allow you to get to a repair shop. Have autozone clear the codes and see if it acts up again. Usually, limp-in mode can be stopped by stopping the car, turning it off, and re-starting it. Codes will remain stored in the computer until cleared by an automotive technician.

When the system goes into to Limp Home mode it means that a serious fault has occurred in the electronics or a mechanical failure has been sensed. What you need to do now is have the computer control system scanned for fault codes, this (the fault codes) will give you a starting point to diagnose the problem that has caused the Limp Home mode to be initiated by the computer control module.

This is classic limp in mode. The computer won't let it shift to prevent further damage to the transmission. Gas mileage will go down because you're stuck in low gear. P0700 is a pretty general code. You need to get it to a shop for a diagnosis

P0455 = Evap leak monitor large leak detected.
This code usually means the gas cap may have been loose or needs the rubber gasket.

P0500 = No vehicle speed sensor signal.
Vehicle speed sensor is located on the transmission near one of the axle shafts (it may need replacing).

P0700 = EATX controller DTC present.
This simply means you have transmission related codes.

P0732 = Gear ratio error in 2nd gear.
This code is of some concern, it means the transmission is slipping in 2nd gear. However the trans may be in limp mode due to the speed sensor code (limp mode means the trans starts out in second gear in order to at least get to a mechanic). The first thing I would do is have these codes cleared as there may be absolutely nothing wrong with the transmission (especially if you pull the trans dip stick and the fluid does not have a burnt smell. The vehicle should drive normally after that. If the check engine light comes back, have the codes scanned ASAP (before any other unrelated code sets). Chances are it may be the output speed sensor if this happens (easy fix). Hope this helps

Regards

The town and country vans are know for transmission problems and it would not be stuck in 2nd gear if it was in limp mode. Limp mode typically controls the engine. I have seen people do a transmission flush/filter and add lucas to temporary fix the problem. There is also a good chance that the transmission has a solenoid problem preventing it from shifting into any other gears but second. Hope this helps!

the PO700 code is a generic transmission code. You would need access to a proper scan tool to check for transmission codes. However if you speedo isnt working, it sounds as though you have a bad output speed sensor. This part runs about 60.00 from the dealer, and is fairly easy to install. No speed signal will put the transmission into limp mode, and keep it stuck in 2nd gear.

Darrell, The trans went into limp mode. 41te trans do funny things. The limp setting is so you can get home or to the dealer. As for the slipping , check fluid first. If ok scan for codes from trans...

This is called the limp mode. It means that you have a transmission problem. It goes into limp mode to protect the transmission from total failure. You need to take it to a transmission shop to perform a diagnosic test to see if it needs repair or replace

MCARTER859: check the connections where the transmission harness and engine room harness come together. Unplug them and reconnect them I have run into more than one case with the same symptoms as yours which ended up being nothing more than poor connections.
CROSS YOUR FINGERS1

unhook the battery for about 15 minutes and hook it back up... that should reset it