How do I clear P1740?
 

First of all, my truck shifts fine and lockup works great. Whatever condition threw this code was apparently transient. The check engine light is off. But, this code pops up with the ignition sequence to recall codes. I have to get a smog check done in the next month. So, I need to clear this code. I have a cheap OBDII reader that I bought from Amazon. It cleared some other codes that I had due to weak batteries (since replaced), but this one won't clear. It reports the code, then acts like it's clearing it, but it just stays there. Because this is a transmission related code, could it be stored somewhere else? Can anyone tell me the best way to clear it? Sounds like a good excuse to get a Smarty.

I have seen some code readers not clear all codes in the ECM or TCM. You could try going to autozone or somewhere similar to see if they can clear it. It may be that there is actually a problem so the code clears and immediately resets.

I thought of that as well. However, it is a transmission related code and it would have to reset before even starting up the truck. Also, it doesn't turn on the check engine light. This code has been in there for well over a year and the transmission shifts just fine. I have a feeling it threw the code when my batteries were really weak (since replaced) and my cheap code reader just doesn't clear this one.