When you say PCU are you referring to the PCM? If so, you cannot just replace this part. It requires you to program the replacement module. I attached the process on how to do this. It requires the use of a scan tool so if you don't have one then you will need to have a shop program it for you.
However, you are correct in that the vehicle thinks it is being stolen so it locks out operation until until it is programmed properly.
Please let me know if I am missing something with what your issue is. Thanks
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Sunday, July 28th, 2019 AT 10:11 AM