2004-silverado-switched-power-source Apr 2026
According to multiple Silverado owner forums, the most reliable and easiest place for switched power is the passenger-side dashboard fuse box.
This requires a bit more navigation than the fuse box. 3. Ignition Switch Harness 2004-silverado-switched-power-source
There is often an unused relay socket (upper left) that provides 12V key-on power. According to multiple Silverado owner forums, the most
This circuit is often controlled by RAP (Retained Accessory Power), meaning it stays on for 10 minutes or until you open the door after turning off the key. 2. Under-Dash Relay Panel (Above Brake Pedal) Ignition Switch Harness There is often an unused
For clean, safe tapping into the fuse box.
Unlike older trucks, the 2003-2006 Silverado/Sierra trucks (GMT800 platform) are heavily controlled by the CAN-bus system, meaning many fuses in the dashboard remain live (constant power) even after you turn off the truck. This can lead to parasitic battery drain and a dead battery!
Use an "Add-a-Circuit" (fuse tap) for a clean install. Note that this is often a 3-pin fuse slot, so you may need a specialized mini add-a-fuse.