P0410 OBD2 Fault Code: Diagnosis and Repair for 2002 Buick Lesabre Custom 3.8L Engine

I recently replaced the secondary air pump housing (not the filter side) and installed a new check valve (Dorman 911-004 Air Check Valve) along with a new electric pump (Dorman 306-010). Despite these replacements, the P0410 fault code remains active. Prior to the repair, there was significant moisture in the system, which has now been fully drained. The mechanic confirmed that all hoses are intact and functioning properly. I'm wondering if my 2002 Buick Lesabre Custom has a dedicated fuse for the secondary air pump system—should I check it? Since the pump appears to be operational, I suspect it's not a fuse issue. However, as a novice in automotive diagnostics, I'm unsure of what other steps to take. Any guidance on troubleshooting this P0410 code would be greatly appreciated.