clear ecm/pcm error message

I repleaced the tcc ( torque converter clutch) solenoid circuit in 96 olds cierra 3.1 w/4T60E tranny. After reset the error code p1864 will not stay cleared more than 4 seconds before it pops up again on my Matco obd II scanner. any ideas on how to reset and clear code for good? do you think the pcm is bad. Please help if you can.

olds75dk