Dodge Repair: replaced ecm but check engine light is still on., autoparts store, emissions test

Question
QUESTION: I have a 2001 seabring 2.7 . We have to do emission tests, however they will not even test it if any lights are on. It doesnt matter why the lights are on, they wont even check it. We took it to the dealer they checked the code it was P0601. They want close to a thousand dollars to replace it. We went online to buy a rebuilt unit. They flashed it with the vin number, and mileage. We replaced it but the check engine light is still on. Any ideas as to what else we could do ?

ANSWER: Hi Hank,
The light may still be on because there is a separate fault code from the earlier 0601. You were correct in replacing the pcm. I would get a 'fresh' fault code readout. You can often get it for free at a nationwide autoparts store such as Autozone or an independent shop will usually do it for around $40. Let me know what code number comes out and we'll go from there.
Please 'rate' my answer (see PS below).
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: Hi Roland,he code
Just checked the code with the "key dance" wish I would of known that trick before paying $95 to the dealer. But anyway the codes that came up were the P0601 and the P1864. We did disconnect the battery to try and clear the code, but it hasnt worked. Is it possible that it will knock off on its own after driving it for a few miles ? Or is likely that if we knock the code off it would stay off ?  Thanks for any info, we really need to get the car through the emissions test.  Hank

Answer
Hi Hank,
Disconnecting the battery (which causes another 1684 nonetheless) should erase the 0601 so it suggests it is still valid. The fact that it didn't (and you could try it again) would cause me to believe that the used pcm is defective. I would question the vender for a replacement given that the 0601 can only be 'cured' by replacing the pcm. I wish there was hope for a spontaneous clearing of that code but I would not hold out much hope for that.
Please let me know how this is resolved.
If you would be so kind as the rate my answer and consider saying 'yes' to a nomination of me it would be most appreciated.
Roland