Sensors and electrical components in the 2004.5–2007 5.9L Cummins monitor and manage engine performance, emissions, and fuel delivery. Key sensors include the MAP, crankshaft, camshaft, ECT, and boost pressure sensors, all of which feed data to the ECM for real-time adjustments.

Wiring harnesses, relays, and connectors ensure these components communicate effectively. Faulty sensors can lead to poor performance, hard starts, or check engine lights, making diagnostics and replacement critical for reliability and efficiency.