P0123 Fault Code Reappears on 2001 Ram 1500 Despite Repairs and Battery Disconnection

My 2001 Ram 1500 with a 5.2L engine has been consistently displaying the P0123 fault code since yesterday. We have already replaced the throttle position sensor (TPS) and performed multiple battery disconnections—each lasting 30 minutes—to reset the system. The issue persists after each attempt. We removed and reinstalled the TPS twice, and even replaced the IAC valve with no improvement. After disconnecting the battery, we waited 5 minutes before reconnecting and performed a full diagnostic cycle by turning the key three times, holding the trip reset button, then turning off the key. The P0123 code still appears during the self-test sequence. We have ruled out simple electrical issues and are confident in our diagnostics process. Despite thorough troubleshooting, the code returns every time. Any insights or known causes for this persistent P0123 error on a 2001 Ram 150 or potential next steps would be greatly appreciated.