I have a new transmission with about 2500 miles on it. It's a Performabuilt (PB) Heavy Hauler 4l60e. The torque converter just stopped locking one day. The PCM is commanding lockup but nothing happens. Not like its slipping, like nothing. The only thing I noticed that seemed strange is that when monitoring TCC Lockup on the scanner, Is goes to "YES" any time I'm moving. I have it set to lock only in 4th above around 50 mph. I also have minimum pulse width set to 99% and maximum to 100% so that it either locks or not. I contacted PB and they quickly sent me a new TCC Solenoid but replacing it didn't seem to change anything. Is there anything else I can do to try to diagnose this issue?