On Wed, 30 Apr 2008 01:51:02 -0700, "Ted Mittelstaedt"
<tedm@[EMAIL PROTECTED]
> wrote:
>
>"Doug" <sparks06524nospam@[EMAIL PROTECTED]
> wrote in message
>news:778g14pqvjl19jsosismr1f4h20q0es752@[EMAIL PROTECTED]
>>
>>
>> A friend has a 1996 T&C with the 3.8l engine.
>>
>> On damp or rainy days, the transmission suddenly kicks down into
>> second, even if the vehicle is going at a high rate of speed - awkward
>> on the highway. From the technical literature that I've read, it seems
>> like it's going into the limp home mode.
>>
>> From the wiring diagram in a similar year tech manual, there are quite
>> a few sensors and/or connections that can activate the kickdown relay.
>>
>> We took the van to a local Chrysler dealership and they insisted that
>> the problem was caused by a bad alternator.
>> The only thing wrong with that alternator (which I already knew) was
>> minor bearing wear. I insisted that replacing it wouldn't help the
>> transmission problem. They insisted that since I was not a "factory
>> trained tech", I didn't know what I was talking about.
>>
>> My friend paid to have the alternator replaced and of course it didn't
>> help. One week later in the rain, the transmission kicked down again
>> at 65 MPH. On dry days, all is perfect.
>>
>> I asked the dealer service manager if they had scanned the error codes
>> and he replied saying "we did was was required".
>>
>> Needly to say that my friend and are are disgusted with the
>> dealership.
>>
>> I've pulled apart and cleaned with electronic contact cleaner all
>> connectors to the power control module, pulled all relays and fuses,
>> the PCM, visible sensor connections, etc to no avail.
>>
>> Anyone have any suggestions?
>>
>
>anytime the trans goes into limp mode a code is set. I think the
>dealership saw an opportunity to make some money since I am quite
>certain they sold your friend an alternator at a cost far in excess of
>a simple rebuilt unit. Naturally if they didn't scan the trans then they
>would not be able to tell you the code that was set!
>
>Anyway, I own 2 T&C's a 94 and a 95 and done considerable work
>on them. I would strongly recommend you replace the
>"turbine sensor" aka input speed sensor. These hall-effect
>sensors get intermittent when they get older and will cause this problem.
>I actually think that they are the only part in the transmission that
will
>cause this without an accompanying other symptom, such as a big
>grinding noise or some such. For some idiot reason known only
>to Chrysler's transmission designers, the software in the trans computer
>will immediately slam the trans into limp mode even at a high rate of
speed,
>if the signal is lost from the input speed sensor for even a fraction of
a
>second, and if signal reappears from the input speed sensor it will
>-keep- the trans in limp mode until you shut off and restart the car.
>
>I would discount the rain issue, frankly. The fact of the matter is that
>unless your going at a high speed, it is not easy for your typical
>ignorant driver to even be aware that the trans has shifted into 2nd.
>I strongly suspect that this trans has been doing this for some time now,
>and your friend has somehow made some unconscious assumption that
>it is due to water, so now he only notices it happening when it is
raining.
>
>Ted
>
Ted,
Thanks for your input but NO, it definitely happens ONLY during
wet/damp/high humidity days.
I've driven the vehicle under multiple conditions on dry days and
operation is perfect.
Another clue is that OCCASIONALLY when the transmission slaps into
limp mode, the window wipers will start operating when their control
switch is in the off position.
I'm thinking ground, connector corrosion and/or an alternative current
path.
Now, could the output of that speed sensor be intermittent on damp
days? Sure it can if there is some corrosion, etc on its wiring.
I don't know how to explain the apparently simultaneous wiper problem
unless there is some common ground point that begins to float.
That doesn't seem to be the case per the tech manual.
Nevertheless, you've given me some additional hints.
What is the physical location of the transmission input and output
speed sensors for a 1996?
Doug
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