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Year 2000 Silverado 2500HD - power always on in the cab


New Member
Jan 29, 2024
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Houston, TX
Year 2000, Silverado 2500HD 4x4, 6.0 gas. A shop replaced the electrical harness as part of (or in addition to) repairing drilled out ignition lock cylinder (thieves). The battery is constantly being drained and I never know if it will start in the morning. The clock on the radio is always illuminated, I can turn the radio on, power windows are always available, can turn on headlights, indicators, basically everything all with the key in my pocket.

In my mind something is crossed at the fuse box but I'm just a guy who knows a little about trucks.

This might be above my skillset but if someone knows a relatively simple place to start investigating I'll start there. This has stumped some technicians though, maybe due to the age of the vehicle. One shop had it for 6 weeks and got nowhere. Thanks for reading this and any suggestions!
Look underneath the underhood fuse box, often times the wiring gets damaged from rodents. Usually mice. I need to check a wiring diagram, but I believe there is an accessory relay in the underhood fuse box