This thread should be moved to the 4T65E section

The TCC solenoid is located on the valve body along with all of the other solenoids. This code is set after driving and TCC is commanded, torque converter clutch lockup which is a clutch inside the torque converter to eliminate torque converter slippage, reduce heat, and improve fuel economy. There is a pressure switch that is part of a pressure switch manifold that is mounted on the valve body and has fluid passages that apply or release the pressure switches so the pcm knows what range the shifter is in and also if there is TCC apply fluid present or not. This is used so the pcm knows that the transmission is hydraulically functioning properly. Code P1887 may set even if everything works fine but the pcm does not see the correct position of the tcc pressure switch. This could be be caused by a few different problems and from the electrical standpoint a faulty pressure switch manifold, damaged wiring inside the trans, damaged underhood wire harness, pcm connector or pin bent or making bad connection, pretty much anything between the switch and the pcm. From a mechanical/hydraulic standpoint IF lockup IS working ok then you are likely ok. If lockup is NOT working ok then you typically have a code P0742 or P0741 present first, but inside the trans if the input shaft oring or seals are bad, seperator plate where lockup checkball has smashed through the plate or stuck in the plate, plate has debris blocking the hole or valve body gaskets are damaged, stuck tcc apply valve. These are just a few things that could cause it but it is best to check the electrical end of the problem first to rule out trans. A road test with a scan tool will verify pressure switch position which should also be checked out. A thorough diag will find your problem but replacing the tcc solenoid and not checking anything likely will not fix anything for you.