Terminator X searching for ECU

[ASUNDVL]

Haven’t been on here as much lately, but hoping I can tap into the collective wisdom please. Trying to finish up the install of Holley terminator x system in my chevelle (LQ9 and T56) but when I first power up the system the handheld screen never gets beyond searching for the ECU. All LED’s on the ECU are powered during this time.

if anyone has suggestions for how to troubleshoot it would be hugely appreciated! After a fair bit of searching on the Holley website I can’t find any next steps and customer service is unavailable for the holiday weekend.

Thanks for any suggestions!!

Jason