Well since my engine light is still on after replacing a sensor and the PCM which the dealer found had a short, I was wondering if anybody else has taken their truck in for an inspection, did this code cause the vehicle to fail the OBD check.
I still need to take mine back to the dealer to see if I need the PCM reprogrammed to clear the code problem. I did order a PCM on-line and it should have been programmed to the correct year and mileage.
I did make it 350 miles with the new PCM and no check engine light. My inspection is not due until June 2014, so looking to the future.

 

P1740 is a torque converter clutch or OD Solenoid performance code.

"A rationality error has been detected in either the TCC solenoid or overdrive solenoid systems."

Are you noticing any problems with overdrive?

 

No problems with overdrive, seems a little sluggish at first starting out, but shifts ok. The rpms drop after stepping on the throdle, does not continue reving. I have the OD on all the time and have driven it with the OD off and no problems that I can tell. Fluid level is correct, filter and fluid was changed when the sensor was replaced. Have erased the codes, but comes back on within 2-3 days.

 

You may need to have the dealer perform a Torque converter stall test. Because the problem could be a torque converter and front pump or the hole on the TCC plate is too small.

 

what sensor was replaced?

IIRC 1740 = PCM language of "Hey, the RPM's aren't dropping when they should be. CODE!"

 

The paperwork only says A31 Sensor, the dealer does not say which solenoid it was. I also asked about the TTC plate recall and they said this hole dia problem was only associated with the 46RE transmission and does not affect the 42RE that is on my truck. The backflow valve in the transmission line is working ok, they checked that also. I have had it in twice to the dealer and would assume they did a stall test to find the sensor was faulty.

 

Try switching out the e-fan relay in the underhood power center. That relay also controls some of the electronic shifting functions. There should be another relay in there that will interchange (probably an a/c relay) so it won't cost anything to try.

If it seems sluggish starting out, it sounds like the trannie is starting in second gear.

Been there, done that, btw.