Engine/Transmission (1998.5 - 2002) P code 1740: TC or OD solenoid

[paguilera]

I have a 02' with a BD torque converter and valve body and a Suncoast billet rebuild ( 5k miles since rebuild and new t/c)... the unit runs great, adds power and is a joy to drive. Only one issue..... once and a while, usually when I am going in and out of OD... it sets a P1740.



Both the trans builder and my dealer... yeah go figure, say it is because the stock software can't deal with how efficient the BD tc is. Both say it is just an advisory code, (not the M code) and I should just clear it... (I do have a reader/clearer) and I have done that a couple of times. I don't think the code seems to have any impact on the way the truck runs(could it??)... it hasn't set again in the last couple of months, but I haven't been doing any towing and in/out of od.



Anyone know if this is right or bs... or if I am developing a problem by clearing the codes???





Alas, during my last tow home (with boat and camper), in Sept (hot oat*) I got the dead pedal twice, both times while accelerating onto the freeway or climbing hard at low speed... the apps checked fine... so I guess I will be replacing my IP before the next Baja trip... . ain't easy to get one down there... . but, of course it hasn't acted out once since sept.

Thanks for the input, Paul



PS thanks Black Sheep Diesel, for the input on the steering noises... it worked.

 

[JLandry]

Paul,



According to the Dodge Diagnostic manual, there's a long list of things that can contribute to a P1740 DTC being set. Finding the exact cause will depend on how much effort you want to put into it.



If you PM me your email address, I'll send you a copy of the 6 pages dealing with this from the diagnostic manual. The file size limitations of the forum prevent me from uploading it.



In reading over the diagnostic procedures, it looks like a DRBIII scan tool would almost be essential in conducting many of the suggested tests, which includes comparing sensor outputs and conducting transmission tests.



Best regards,



John L.

 

[paulb]

The CA models have this problem more then the 49 state version. Your dealer is basically correct. What the CA computer is looking for is a change in rpm when the converter locks. With a "tight" converter you may not get the rpm drop that the computer is looking for. Driving like a grandma also contributes to the code being set.



I had this code set with the first DTT converter I had, but the later ones I did not have the problem. I also have not had the code with the Ultimate Transmission converter I currently have.



The code setting won't cause a problem, nor will clearing it.



Paul

 

[jandr]

I am just starting to get this code. P1740. I have a 2001(Calif. Truck) with a DTT trans. The trans has about 39,000 miles on it. It never threw this code until recently. And only after this most recent fluid and filter change. ATF+3 and Napa filter. The open type filter that the DTT tech recommended. (I think it was for a '96)

Any thoughts on fluid type differences or brands? Filter is the same style as DTT had in it. Why now and never before if it's just the better quality TC?

I just had to smog the truck, so I had to clear the code right before I took it in. And good thing. They looked for the check engine light and hooked into the port to check for codes. It's more of a big deal now than before since smog checks were implemented.

Since it wasn't being thrown before, seems reasonable something has changed.