1992 Caravan Transmission Problems

Hi everyone!

My uncle is having a few problems with his transmission and we were hoping form some good advice. While driving at slow speeds it will shift to 2nd gear and lock into it. If we shift to natural and shut off the car then restart it, then it will shift back to first. We have replaced two sensors on the tranny and just replaced the alternator. We have heard that a low voltage out of the alternator can cause the problem, but our new alternator did not solve our issue.

Thanks for any words of wisdom.
Mike

The transmission is going into limp in mode(2nd only)
Does the check engine light come on?
Check for trouble codes by cycling the ign. switch
3 times(on-off-on-off-on)and count the flashes of the
check engine light.
Or take it to a transmission shop for diagnosis.
You never know it might be something simple.

HTH
Marc

After cycling the swith 3 times we get the code 55, which means no problem with the computer. We have also had it check by the parts store and they could not find any errors with their diagnostic machine.

Mike

Hi everyone!

My uncle is having a few problems with his transmission and we were hoping form some good advice. While driving at slow speeds it will shift to 2nd gear and lock into it. If we shift to natural and shut off the car then restart it, then it will shift back to first. We have replaced two sensors on the tranny and just replaced the alternator. We have heard that a low voltage out of the alternator can cause the problem, but our new alternator did not solve our issue.

Thanks for any words of wisdom.
Mike

What engine is it? 3 speed or 4 Speed (PRND3L).Mileage of vehicle. When was the transmission serviced? The transmission is engaging in what is called the LIMP MODE. I am assuming it is a four speed. It appears you have changed the input and output sensors. The more info you can give us the better someone may be able to help you.

Is fluid level ok
IS CEL on
CHECK for Codes and post ( Turn ignition switch OFF/on, off/on/ off/on the cel will flash giving you code #'s if any are present. Example: flash pause flash flash means code 12- battery has been disconnected recently.)
Clean battery posts and ground wires
Make sure all conectors are clean and tight on sensors
Check for moisture in the 8 pronge connector to the solenoid pack. (Connector under fluid lines going to radiator from trans)
Check connector at TCM (On my 93 it is located on passenger side firewall) for loose or corrided contacts.

Check out these sites:
http://www.robskorner.org/faqs/Trans/A604comploc.html
http://www.allpar.com/fix/trans.html


Hope this helps

Do what he suggests, then also change the fluid with ATF+4, and use a real Mopar filter whhen you do. Yes, you can use ATF+4 on the earlier models of A604.

If that doesn't work, it could be a grounding problem. Or, the TCM needs to be reflashed. That update needs to be done at a Dealer or Transmission shop.

Some TCM updates reduce needless Limp in problems, like what you may have now.

There were a lot of mechanical updates done between 1992 & '96, but that's last resort.

Thanks for the advice so far. We have replaced the TCM relay, as suggested on a web site with no luck. Next we are going to have the TCM flashed and see where that leads us. I will update if that does not work, and maybe someone can send us in another direction.

Thanks again,
Mike