Expert: Roland Finston - 10/10/2005

Question
Hi Roland, 97' Dodge caravan 3.3 engine 4speed automatic. Gone into limp, changed trans fluid  & filter, changed input & output sensors, changed
selinoid pack, changed transmission computer and still goes into limp mode. Took battery cables off to wipe computer, checked with code reader and no codes. Test drove car and still goes into limp mode. Going crazy here ! What do you suggest that I try next? Pete told me to change the TCM, but I had already told him that I changed it out already... Can you please help me.
Very Frustrated in Florida,
Perry Edwards

Answer
HI Perry,
It seems to me you have tried everything that is reasonable to do without having all the fault codes to work with. My main question is what sort of code reader did you use and what was the plug like that you used to attach the reader and where was the plug located? The '97 model year was on the cusp of the OBD-I to OBD-II change over, and so it is entirely possible that you only read out the trouble code memory of the PCM and not of the TCM. Under the OBD-I you had to read the TCM with a different plug design from that which you read the PCM. The plugs were in different locations: PCM under the hood, TCM under the dash. The ignition key trick only got you the PCM codes. It varies by model/year as to which plug(s) you have in your van
Then the OBD-II came in with a new plug under the dash which read both units, if you had the DRB-III reader. So reflect on that situation and perhaps see if you can get a better readout done (at a Chrysler dealer) which will tell you the codes stored in the TCM. I don't believe it will go into limp in without setting a code. I have a couple of manuals for the A604 so when you get the codes write back and we'll compare notes.
Roland