Did some testing with my sync 3 radio yesterday..... I will need to do some digging around and reprogram the APIM on my Sync 3 APIM. My radio faceplate does not light up with the Sync 3 pluged in but does with the old Sync 2 pluged in. GPS is also innacurate at times and my clock resets to 1200 at times. I've read somewhere that the clock master has to be synched with the APIM when switching from Sync 2 to Sync 3. I probably need to pull the as built values from a 16+ that has the exact same options as my 15.