I keep having my check engine light coming on in my '01 Dodge Ram 1500 4X4. It has the 5.9L engine in it and my mechanic can't figure out why the light won't stay off. The light code is P1740, which it says is the overdrive solenoid. My transmission needed servicing so I figured I would go ahead and get that done. Well, the engine light came on again. It seemed to do it when I turned my OD off. Does anyone have a clue what could be causing it?? I really don't need to have something major go wrong with it since I am trying to sell it. I am hoping that the dirty tranny fluid just clogged the solenoid or something and it is a cheap fix. But the dealer wants at least $85 to even look at it. Any help is always appreciated. BTW, it is an automatic.

 

Welcome to the DF! I just wanted to say that first. I don't know the answer to that problem, but I guarantee there is a least a handful of guys on this board that do and I don't think that they are on at the moment but check you post later. I'm guessing here but it sounds like you have a vaccum leak mabye.

 

according to the code list I have it says "Torque Converter Clutch Inductive Signature Malfunction"... to me it means the TC is not locking or unlocking properly... take it out on the freeway and at about 60 mph, downshift into 3rd and watch the rpm's on the tach. you'll be looking for a 200~300 rpm jump in rpm's before it downshifts to 3rd. I had this problem before and it didnt throw a code (obd I). when you put OD on again, you should see that 200~300 rpm shift again, that's when the TC is locking. if it doesnt do this then take it back to the tranny shop asap. if the TC breaks, your looking at a re-build if the chunks get in the wrong spots.

let us know what you find...

 

Hey, I'm having the same problem with my truck. I had the solenoid switches replaced twice now. Did you ever get it fixed?

 

as the original thread is over a year old... I dont think the original poster is around...