Hey guys, I have a f150 2002 with a 5.4 and 4r100 (yes im sure), and a week ago my torque converter started getting stock (locked) when i came to a stop making the engine stall (it took a couple of minutes before my engine got warmed up). I checked the codes and got 0740 and 0743 which relate to the tcc solenoid malfunctioning. To make sure the tc wasn't physically stuck y cut the purple wire that signals the solenoid to lock the converter, the truck ran fine and as expected the tcc never locked, so I thought I norrowed it down to the solenoid pack, which i bought (300 bucks ouch) and changed it yesterday. Today again the same thing started happening and the truck is throwing me the same codes, so im a bit frustrated. I don't wanna go ahead and buy a torque converter without knowing the real cause, any ideas of what could it be? I didnt see any melted wires down there but could my long tubes be shorting that wire out randomly in an unseen place? or could my tc be bad?

 

If the torque converter were bad cutting the wire wouldn't make any difference. Since cutting the wire solved the problem the problem is in the wire or the PCM. If it is the wire the problem is located between the PCM and where you cut the wire.

 

Mark is correct.

Either the PCM's ouput driver is shorting internally to ground or the VT/YE wire to the TCC solenoid is intermittently shorting to ground (which causes the solenoid to energize and apply the TC clutch).

There was nothing wrong with the solenoid pack.

 

Thanx To both,

one other thing, I had an idle issue with my truck also which ended up being a short in the pcm messing up the readings of the tps(now fixed), is the tc solenod cable related or conected somehow to the tps or does it go directly to the pcm?

 

They're both in the same connector to thee PCM (there's only one big one).