I suspect theft communication is critical and before it got initialized ccm wont go over normal communication mode and will loop the pcm till hadshake is good, Also at reset or ign on if modules are powered at different time it might be an issue.

spfautsch points at the start of the thread that the ccm polls change from 0000 to xxxx to ffff and than works as normal.

Actually that poll is some seed to pcm and pcm will return key at 41 response word_1983